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Master Spring Boot 3 from IoC/DI, Starters, Auto-Configuration & DispatcherServlet REST APIs to ProblemDetail Exception Handling, Jakarta Validation, Spring AOP, HikariCP + Spring Data JPA (solving N+1), Caching, Spring Security 6 JWT & Actuator — with runnable Java 21 programs, 10×50 MCQ Mock Tests per topic, and Spoken Voice + Gemini AI Interviews at ₹4,499.
SPBT • Java Enterprise Backend & Microservices Engineering
Duration & Live Format: 16–18 Weeks • Live + Hands-On Projects (208h • Weekday & Weekend Batches)
🔒 100% Fixed Tuition: Zero bargaining or quality compromise on Senior Architect trainers & live labs.
✓ 16 Module Repos + Live Client Prod Project + Barcode Certificate & Official Internship Letter
Our counselor shares live demo link & issues your Student Portal ID to track every topic transparently.
Spring Boot is the #1 enterprise framework for Java. It eliminates thousands of lines of old XML configuration so engineers can launch secure, bank-grade REST APIs and microservices rapidly.
Starts from clear explanations of APIs and Dependency Injection so learners with basic programming familiarity (or Java fundamentals) smoothly grow into enterprise backend engineers.
Core Industry Skill Pillars You Will Master (In Bullet Form + Exact Purpose):
For What Purpose: Wire clean, testable business services automatically across dev, staging, and prod environments.
For What Purpose: Expose standardized, validated JSON REST APIs with consistent enterprise error contracts.
For What Purpose: Persist relational entities cleanly while preventing hidden SQL performance bottlenecks.
For What Purpose: Guarantee zero partial writes during payment/order failures under heavy concurrent load.
For What Purpose: Lock down enterprise endpoints with stateless tokens, OAuth2, and fine-grained role policies.
For What Purpose: Ship observable, documented, integration-tested microservices ready for cloud clusters.
For What Purpose: JUnit 5 • MockMvc slice tests • Testcontainers (real PostgreSQL in CI) • OpenAPI 3 documentation — ensuring your code never breaks silently when real users hit edge cases.
For What Purpose: Verify every single Springboot topic through timed MCQ exams and spoken technical interviews before deploying your Live Client Project.
Live trainer-guided cohorts with 100% transparent topic-by-topic tracking.
Springboot Training — Affordable ₹4,499 Live Cohort
Mon - Sat • 09:00 PM - 10:30 PM IST
Starts: 10 Oct 2026
Every student who completes training modules and deploys the end-of-course Live Client Production Project receives both a scannable Barcode Certificate AND an Official Project Internship Confirmation Letter detailing exact engineering contributions.
Inspect Live Sample Certificate & Internship Letter →Only enrolled students can log in to inspect batch timing, assigned tasks, content covered & pending, unlimited Mock Tests & Voice AI Interviews, projects assigned to batch & status, batch group chat, and daily recorded class videos.
Clean Spring Boot 3.3 architecture with constructor injection, immutable DTO records, and Bean Validation (`@Valid`).
Spring Security 6 stateless OAuth2/JWT filter chains, CORS configuration, and method-level RBAC authorization.
Hibernate / Spring Data JPA performance: solving N+1 queries, optimistic locking, projections, and Flyway migrations.
Resilient external integrations with RestClient, Resilience4j retries/circuit breakers, and Spring Cache.
JUnit 5 • MockMvc slice tests • Testcontainers (real PostgreSQL in CI) • OpenAPI 3 documentation
Spring Boot Actuator health/metrics endpoints, Micrometer tracing, and layered Docker image builds.
Field `@Autowired` injection, exposing JPA entities directly in REST responses, and `ddl-auto=update` in prod.
1.5 Hours / Day (60 Mins Live Architecture & Coding + 30 Mins Hands-On Lab)
Days: Monday to Friday (5 Live Interactive Classes / Week)
Slots: Morning: 08:00 AM – 09:30 AM IST • Evening: 07:30 PM – 09:00 PM IST
3.0 Hours / Day (2 Hrs Deep-Dive Live Coding + 1 Hr Guided Project Build)
Days: Saturday & Sunday (Designed for Working Professionals & College Students)
Slots: Morning: 10:00 AM – 01:00 PM IST • Afternoon: 03:00 PM – 06:00 PM IST
100% Live Interactive Format: Live instructor coding, screen-share debugging, daily lab assignments, and HD session recordings inside your Student Portal.
After completing 10+ progressive hands-on module projects during live classes, students join our mentor-led Client Production Sprint to build, test, and deploy "MediTrack Secure Enterprise REST API, RBAC Portal & Scheduled Billing Service" to live cloud production — earning an Official Verified Internship Letter detailing their exact technical contributions.
🚀 Real Client Production Sprint + Internship Letter
Client / Domain: Healthcare Clinic Network & Insurance Claims Client • Production Infra: Java 21 + Spring Boot 3.3 + Spring Data JPA + Spring Security 6 JWT + PostgreSQL + Docker
What Your Official Internship Confirmation Letter Certifies You Built & Deployed:
Click any module or topic below to expand its learning objectives, plain-language overview, real-world purpose, hands-on code, lab tasks, 50-MCQ mocks, Gemini AI interviews, and capstone project.
Module Learning & Hands-On Objectives
💡 Self-Explanatory Overview: In simple, everyday terms, Spring Boot 3 Overview — Opinionated Defaults, Embedded Servers & Zero-XML Philosophy teaches you how Springboot applications how Spring Boot wraps the Spring IoC Container (`ApplicationContext`) with opinionated Starter dependencies, Conditional Auto-Configuration, an embedded Tomcat/Jetty/Undertow server, and production-ready Actuator metrics. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Spring Boot 3 Overview — Opinionated Defaults, Embedded Servers & Zero-XML Philosophy in real Springboot systems — specifically: How Spring Boot wraps the Spring IoC Container (`ApplicationContext`) with opinionated Starter dependencies, Conditional Auto-Configuration, an embedded Tomcat/Jetty/Undertow server, and production-ready Actuator metrics, so your code stays reliable, fast, and easy to maintain in production.
Spring Boot Tutorial provides basic and advanced concepts of Spring Framework. Our Spring Boot Tutorial is designed for beginners and professionals both. Spring Boot is a Spring module that provides the RAD (Rapid Application Development) feature to the Spring framework. Our Spring Boot Tutorial includes all topics of Spring Boot such, as features, project, maven project, starter project wizard, Spring Initializr, CL...
Spring Boot 3 Overview — Opinionated Defaults, Embedded Servers & Zero-XML Philosophy — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Spring Boot 3 Overview — Opinionated Defaults, Embedded Servers & Zero-XML Philosophy using @SpringBootApplication + SpringApplication.run...
Spring Boot 3 Overview — Opinionated Defaults, Embedded Servers & Zero-XML Philosophy — Actuator, Logs & MockMvc Lab Task
package com.mockattempt.academy;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;
@SpringBootApplication
public class AcademyBootApp {
public static void main(String[] args) {
ConfigurableApplicationContext ctx = SpringApplication.run(AcademyBootApp.class, args);
System.out.println("IoC Active: " + ctx.isActive() + " | Beans Loaded > 50: " + (ctx.getBeanDefi...💡 Self-Explanatory Overview: In simple, everyday terms, Spring Framework vs Spring MVC vs Spring Boot — IoC Container, `DispatcherServlet` & Auto-Setup teaches you how Springboot applications clear architectural boundaries: **Spring Core** provides IoC & Dependency Injection; **Spring MVC** is the web module (`DispatcherServlet`, `@Controller`); **Spring Boot** auto-wires both with curated BOM versions and embedded servers. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Spring Framework vs Spring MVC vs Spring Boot — IoC Container, `DispatcherServlet` & Auto-Setup in real Springboot systems — specifically: Clear architectural boundaries: **Spring Core** provides IoC & Dependency Injection; **Spring MVC** is the web module (`DispatcherServlet`, `@Controller`); **Spring Boot** auto-wires both with curated BOM versions and embedded servers, so your code stays reliable, fast, and easy to maintain in production.
Spring, Spring Boot, and Spring MVC are popular technologies used for Java application development. Spring Framework provides the basic features for building Java applications. Spring Boot makes development faster by reducing configuration work and helping create stand-alone applications easily. Spring MVC is used to develop web applications using the Model-View-Controller design pattern. In this chapter, you will le...
Spring Framework vs Spring MVC vs Spring Boot — IoC Container, `DispatcherServlet` & Auto-Setup — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Spring Framework vs Spring MVC vs Spring Boot — IoC Container, `DispatcherServlet` & Auto-Setup using ApplicationContext (Spring Core) + D...
Spring Framework vs Spring MVC vs Spring Boot — IoC Container, `DispatcherServlet` & Auto-Setup — Actuator, Logs & MockMvc Lab Task
record FeeQuote(String code, int offerInr) {}
@org.springframework.stereotype.Service
class PricingService {
public FeeQuote quote(String code) { return new FeeQuote(code, 999); }
}
@org.springframework.web.bind.annotation.RestController
class QuoteController {
private final PricingService pricingService; // Implicit constructor DI!
QuoteController(PricingService pricingService) { this.pricingService = pricingService; }
}💡 Self-Explanatory Overview: In simple, everyday terms, Spring Boot 4-Layer Architecture — Presentation, Business Service, Persistence & Database Flow teaches you how Springboot applications strict separation of concerns: **1. Presentation Layer** (`@RestController`, HTTP/DTO validation), **2. Service Layer** (`@Service`, business rules & `@Transactional` boundaries), **3. Persistence Layer** (`@Repository`, JPA/JDBC), and **4. Database**. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Spring Boot 4-Layer Architecture — Presentation, Business Service, Persistence & Database Flow in real Springboot systems — specifically: Strict separation of concerns: **1. Presentation Layer** (`@RestController`, HTTP/DTO validation), **2. Service Layer** (`@Service`, business rules & `@Transactional` boundaries), **3. Persistence Layer** (`@Repository`, JPA/JDBC), and **4. Database**, so your code stays reliable, fast, and easy to maintain in production.
Spring Boot is a module of the Spring Framework that is used to create stand-alone and production-ready Spring applications with minimal configuration. It is built on top of the core Spring Framework and simplifies Java application development. Spring Boot follows a layered architecture where each layer performs a specific task and communicates with the layer above or below it. Layers of Spring Boot Architecture The...
Spring Boot 4-Layer Architecture — Presentation, Business Service, Persistence & Database Flow — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Spring Boot 4-Layer Architecture — Presentation, Business Service, Persistence & Database Flow using @RestController -> @Service (@Transac...
Spring Boot 4-Layer Architecture — Presentation, Business Service, Persistence & Database Flow — Actuator, Logs & MockMvc Lab Task
record CourseDto(String code, String title, int fee) {}
@org.springframework.stereotype.Service
class CatalogService {
public CourseDto findFeatured() {
return new CourseDto("SPBT", "Springboot Training", 999);
}
}💡 Self-Explanatory Overview: In simple, everyday terms, Core Spring Boot 3.4 Features — `SpringApplication`, `CommandLineRunner`, Profiles & Java 21 Virtual Threads teaches you how Springboot applications customizing `SpringApplication` (`Banner.Mode`, `ApplicationRunner` / `CommandLineRunner` startup tasks, `ApplicationEvent` pub/sub), environment-specific `@Profile`, and enabling Project Loom **Java 21 Virtual Threads** with a single property!. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Core Spring Boot 3.4 Features — `SpringApplication`, `CommandLineRunner`, Profiles & Java 21 Virtual Threads in real Springboot systems — specifically: Customizing `SpringApplication` (`Banner.Mode`, `ApplicationRunner` / `CommandLineRunner` startup tasks, `ApplicationEvent` pub/sub), environment-specific `@Profile`, and enabling Project Loom **Java 21 Virtual Threads** with a single property!, so your code stays reliable, fast, and easy to maintain in production.
Spring Boot provides many useful features that make Java application development faster, easier, and more efficient. It reduces configuration work and helps developers quickly build stand-alone and production-ready applications. The main features of Spring Boot are: Web Development SpringApplication Application Events and Listeners Admin Support Externalized Configuration Properties Files YAML Support Type-safe Confi...
Core Spring Boot 3.4 Features — `SpringApplication`, `CommandLineRunner`, Profiles & Java 21 Virtual Threads — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Core Spring Boot 3.4 Features — `SpringApplication`, `CommandLineRunner`, Profiles & Java 21 Virtual Threads using CommandLineRunner / App...
Core Spring Boot 3.4 Features — `SpringApplication`, `CommandLineRunner`, Profiles & Java 21 Virtual Threads — Actuator, Logs & MockMvc Lab Task
@org.springframework.context.annotation.Bean
org.springframework.boot.ApplicationRunner verifyBoot() {
return args -> System.out.println("Boot Ready | Java: " + Runtime.version().feature() + " | NonOptionArgs: " + args.getNonOptionArgs().size());
}Architect a 4-layer Spring Boot 3.4 service (`CourseController` -> `CourseService` -> `CourseRepository` -> immutable `CourseRecord`) using zero `@Autowired` field injection, `spring.threads.virtual.enabled=true`, and a `CommandLineRunner` seed verifier.
Module Learning & Hands-On Objectives
💡 Self-Explanatory Overview: In simple, everyday terms, `Spring Initializr` (`start.spring.io`) — Project Metadata, Maven Wrapper (`mvnw`) & Directory Layout teaches you how Springboot applications generating standardized builds via `start.spring.io` (or IDE wizard / `curl https://start.spring.io/starter.zip`), why committing Maven Wrapper (`mvnw` / `mvnw.cmd`) guarantees reproducible CI builds, and root package placement rules. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply `Spring Initializr` (`start.spring.io`) — Project Metadata, Maven Wrapper (`mvnw`) & Directory Layout in real Springboot systems — specifically: Generating standardized builds via `start.spring.io` (or IDE wizard / `curl https://start.spring.io/starter.zip`), why committing Maven Wrapper (`mvnw` / `mvnw.cmd`) guarantees reproducible CI builds, and root package placement rules, so your code stays reliable, fast, and easy to maintain in production.
Spring Initializr is a web-based tool provided by the Pivotal Web Service. With the help of Spring Initializr, we can easily generate the structure of the Spring Boot Project. It offers extensible API for creating JVM-based projects. It also provides various options for the project that are expressed in a metadata model. The metadata model allows us to configure the list of dependencies supported by JVM and platform...
`Spring Initializr` (`start.spring.io`) — Project Metadata, Maven Wrapper (`mvnw`) & Directory Layout — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating `Spring Initializr` (`start.spring.io`) — Project Metadata, Maven Wrapper (`mvnw`) & Directory Layout using curl https://start.spring.io/s...
`Spring Initializr` (`start.spring.io`) — Project Metadata, Maven Wrapper (`mvnw`) & Directory Layout — Actuator, Logs & MockMvc Lab Task
// Root: com.mockattempt.academy.AcademyApp (@SpringBootApplication)
// Scans automatically:
// - com.mockattempt.academy.web.CourseController
// - com.mockattempt.academy.service.CourseService
boolean scanned = "com.mockattempt.academy.web".startsWith("com.mockattempt.academy");
System.out.println("Sub-package auto-scanned by @SpringBootApplication: " + scanned);💡 Self-Explanatory Overview: In simple, everyday terms, Spring Boot Starters & `spring-boot-starter-parent` BOM Dependency Management teaches you how Springboot applications how opinionated `spring-boot-starter-*` poms (`starter-web`, `starter-data-jpa`, `starter-security`, `starter-test`) bundle cohesive transitive libraries while `spring-boot-dependencies` Bill of Materials (BOM) guarantees tested version compatibility. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Spring Boot Starters & `spring-boot-starter-parent` BOM Dependency Management in real Springboot systems — specifically: How opinionated `spring-boot-starter-*` poms (`starter-web`, `starter-data-jpa`, `starter-security`, `starter-test`) bundle cohesive transitive libraries while `spring-boot-dependencies` Bill of Materials (BOM) guarantees tested version compatibility, so your code stays reliable, fast, and easy to maintain in production.
Spring Boot provides a number of starters that allow us to add jars in the classpath. Spring Boot built-in starters make development easier and rapid. Spring Boot Starters are the dependency descriptors. In the Spring Boot Framework, all the starters follow a similar naming pattern: spring-boot-starter-*, where * denotes a particular type of application. For example, if we want to use Spring and JPA for database acce...
Spring Boot Starters & `spring-boot-starter-parent` BOM Dependency Management — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Spring Boot Starters & `spring-boot-starter-parent` BOM Dependency Management using <parent><groupId>org.springframework.boot</groupId><ar...
Spring Boot Starters & `spring-boot-starter-parent` BOM Dependency Management — Actuator, Logs & MockMvc Lab Task
/* In pom.xml <dependencyManagement>: */
// <dependency>
// <groupId>org.springframework.boot</groupId>
// <artifactId>spring-boot-dependencies</artifactId>
// <version>3.4.1</version>
// <type>pom</type><scope>import</scope>
// </dependency>
System.out.println("BOM Mode: scope=import, type=pom -> Aligned versions active");💡 Self-Explanatory Overview: In simple, everyday terms, Executable Fat JARs (`JarLauncher`, `BOOT-INF`) vs External Tomcat WAR Deployment teaches you how Springboot applications how `spring-boot-maven-plugin` (`repackage` goal) creates a self-contained **Executable Nested JAR** (`Main-Class: JarLauncher`, `Start-Class: YourApp`, `BOOT-INF/classes`, `BOOT-INF/lib`), Docker Layered JAR caching, and `SpringBootServletInitializer` for legacy WARs. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Executable Fat JARs (`JarLauncher`, `BOOT-INF`) vs External Tomcat WAR Deployment in real Springboot systems — specifically: How `spring-boot-maven-plugin` (`repackage` goal) creates a self-contained **Executable Nested JAR** (`Main-Class: JarLauncher`, `Start-Class: YourApp`, `BOOT-INF/classes`, `BOOT-INF/lib`), Docker Layered JAR caching, and `SpringBootServletInitializer` for legacy WARs, so your code stays reliable, fast, and easy to maintain in production.
In the J2EE application, modules are packed as JAR, WAR, and EAR. It is the compressed file formats that is used in the J2EE. J2EE defines three types of archives: WAR JAR EAR WAR WAR stands for Web Archive. WAR file represents the web application. Web module contains servlet classes, JSP files, HTML files, JavaScripts, etc. are packaged as a JAR file with .war extension. It contains a special directory called WEB-IN...
Executable Fat JARs (`JarLauncher`, `BOOT-INF`) vs External Tomcat WAR Deployment — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Executable Fat JARs (`JarLauncher`, `BOOT-INF`) vs External Tomcat WAR Deployment using ./mvnw clean package && java -jar target/academy-0...
Executable Fat JARs (`JarLauncher`, `BOOT-INF`) vs External Tomcat WAR Deployment — Actuator, Logs & MockMvc Lab Task
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;
public class ServletInitializer extends SpringBootServletInitializer {
@Override
protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
return application.sources(AcademyBootApp.class);
}
}💡 Self-Explanatory Overview: In simple, everyday terms, Spring Boot DevTools (`RestartClassLoader`), LiveReload & Rapid Local Iteration teaches you how Springboot applications how `spring-boot-devtools` uses a dual-ClassLoader trick (**Base ClassLoader** keeps immutable ` ~/.m2` JARs warm in memory; **RestartClassLoader** reloads ONLY your edited `target/classes` in ~300 ms!), disables template caches in dev, and turns itself OFF in packaged JARs. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Spring Boot DevTools (`RestartClassLoader`), LiveReload & Rapid Local Iteration in real Springboot systems — specifically: How `spring-boot-devtools` uses a dual-ClassLoader trick (**Base ClassLoader** keeps immutable ` ~/.m2` JARs warm in memory; **RestartClassLoader** reloads ONLY your edited `target/classes` in ~300 ms!), disables template caches in dev, and turns itself OFF in packaged JARs, so your code stays reliable, fast, and easy to maintain in production.
Spring Boot 1.3 provides another module called Spring Boot DevTools. DevTools stands for Developer Tool. The aim of the module is to try and improve the development time while working with the Spring Boot application. Spring Boot DevTools pick up the changes and restart the application. We can implement the DevTools in our project by adding the following dependency in the pom.xml file. Spring Boot Code / Configuratio...
Spring Boot DevTools (`RestartClassLoader`), LiveReload & Rapid Local Iteration — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Spring Boot DevTools (`RestartClassLoader`), LiveReload & Rapid Local Iteration using spring-boot-devtools (<optional>true</optional>) — B...
Spring Boot DevTools (`RestartClassLoader`), LiveReload & Rapid Local Iteration — Actuator, Logs & MockMvc Lab Task
String loader = AcademyBootApp.class.getClassLoader().getClass().getSimpleName();
boolean isRestartLoader = loader.contains("RestartClassLoader");
System.out.println("Loaded viaClassLoader: " + (isRestartLoader ? "RestartClassLoader" : "StandardAppClassLoader"));Configure a Java 21 `pom.xml` inheriting `spring-boot-starter-parent:3.4.x`, extract layered JAR segments (`dependencies`, `spring-boot-loader`, `application`) for fast 2-second Docker image rebuilds, and wire `spring-boot-devtools` strictly as `<optional>true</optional>`.
Module Learning & Hands-On Objectives
💡 Self-Explanatory Overview: In simple, everyday terms, Core Stereotype & DI Annotations — `@SpringBootApplication`, `@Service`, `@Bean`, `@Qualifier` & Scopes teaches you how Springboot applications the 3-in-1 `@SpringBootApplication` meta-annotation, `@Component` vs `@Service` vs `@Repository` (which adds `PersistenceExceptionTranslationPostProcessor`!), `@Configuration` (`proxyBeanMethods`) + `@Bean`, `@Primary` vs `@Qualifier`, and Singleton vs Prototype bean scopes. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Core Stereotype & DI Annotations — `@SpringBootApplication`, `@Service`, `@Bean`, `@Qualifier` & Scopes in real Springboot systems — specifically: The 3-in-1 `@SpringBootApplication` meta-annotation, `@Component` vs `@Service` vs `@Repository` (which adds `PersistenceExceptionTranslationPostProcessor`!), `@Configuration` (`proxyBeanMethods`) + `@Bean`, `@Primary` vs `@Qualifier`, and Singleton vs Prototype bean scopes, so your code stays reliable, fast, and easy to maintain in production.
Spring Boot Annotations are a form of metadata that provide additional information about a program. These annotations help configure and manage Spring Boot applications easily. Annotations are not a direct part of the business logic, but they help the Spring Framework understand how the application should behave. Spring Boot annotations simplify application development by reducing XML configuration and boilerplate co...
Core Stereotype & DI Annotations — `@SpringBootApplication`, `@Service`, `@Bean`, `@Qualifier` & Scopes — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Core Stereotype & DI Annotations — `@SpringBootApplication`, `@Service`, `@Bean`, `@Qualifier` & Scopes using @SpringBootApplication = @Sp...
Core Stereotype & DI Annotations — `@SpringBootApplication`, `@Service`, `@Bean`, `@Qualifier` & Scopes — Actuator, Logs & MockMvc Lab Task
interface Notifier { String send(String msg); }
@org.springframework.context.annotation.Primary
@org.springframework.stereotype.Component("emailNotifier")
class EmailNotifier implements Notifier { public String send(String m) { return "EMAIL:" + m; } }
@org.springframework.stereotype.Component("whatsappNotifier")
class WhatsappNotifier implements Notifier { public String send(String m) { return "WA:" + m; } }💡 Self-Explanatory Overview: In simple, everyday terms, Spring Boot 3 Auto-Configuration Internals — `AutoConfiguration.imports` & `@ConditionalOn*` Guards teaches you how Springboot applications how Spring Boot 3 moved from legacy `spring.factories` to **`META-INF/spring/org.springframework.boot.autoconfigure.AutoConfiguration.imports`**, evaluates `@ConditionalOnClass`, `@ConditionalOnMissingBean`, `@ConditionalOnProperty`, and prints the Positive/Negative match report via `--debug`. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Spring Boot 3 Auto-Configuration Internals — `AutoConfiguration.imports` & `@ConditionalOn*` Guards in real Springboot systems — specifically: How Spring Boot 3 moved from legacy `spring.factories` to **`META-INF/spring/org.springframework.boot.autoconfigure.AutoConfiguration.imports`**, evaluates `@ConditionalOnClass`, `@ConditionalOnMissingBean`, `@ConditionalOnProperty`, and prints the Positive/Negative match report via `--debug`, so your code stays reliable, fast, and easy to maintain in production.
Spring Boot Auto-Configuration automatically configures the Spring application based on the JAR dependencies added to the project. It reduces manual configuration and helps developers quickly set up Spring applications. For example, if the H2 database JAR is present in the classpath and no database configuration is defined manually, Spring Boot automatically configures the database for the application. Enabling Auto-...
Spring Boot 3 Auto-Configuration Internals — `AutoConfiguration.imports` & `@ConditionalOn*` Guards — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Spring Boot 3 Auto-Configuration Internals — `AutoConfiguration.imports` & `@ConditionalOn*` Guards using @AutoConfiguration + @Conditiona...
Spring Boot 3 Auto-Configuration Internals — `AutoConfiguration.imports` & `@ConditionalOn*` Guards — Actuator, Logs & MockMvc Lab Task
@org.springframework.boot.autoconfigure.AutoConfiguration
@org.springframework.boot.autoconfigure.condition.ConditionalOnProperty(prefix = "academy.audit", name = "enabled", matchIfMissing = true)
public class AuditAutoConfiguration {
@org.springframework.context.annotation.Bean
@org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean
public java.util.function.Consumer<String> defaultAuditor() {
return evt -> System.out.println("AUDIT: " + evt);
}
}💡 Self-Explanatory Overview: In simple, everyday terms, Externalized Config — `application.yml`, Property Precedence, `@Profile` & `@ConfigurationProperties` Records teaches you how Springboot applications 12-Factor externalized configuration: `application.yml` vs `.properties`, OS Environment Variables (`SPRING_DATASOURCE_URL` relaxed binding!) overriding packaged files, profile-specific `application-prod.yml`, and validated `@ConfigurationProperties` Java 21 `record`s. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Externalized Config — `application.yml`, Property Precedence, `@Profile` & `@ConfigurationProperties` Records in real Springboot systems — specifically: 12-Factor externalized configuration: `application.yml` vs `.properties`, OS Environment Variables (`SPRING_DATASOURCE_URL` relaxed binding!) overriding packaged files, profile-specific `application-prod.yml`, and validated `@ConfigurationProperties` Java 21 `record`s, so your code stays reliable, fast, and easy to maintain in production.
Spring Boot Framework comes with a built-in mechanism for application configuration using a file called application.properties. It is located inside the src/main/resources folder, as shown in the following figure. Spring Boot provides various properties that can be configured in the application.properties file. The properties have default values. We can set a property(s) for the Spring Boot application. Spring Boot a...
Externalized Config — `application.yml`, Property Precedence, `@Profile` & `@ConfigurationProperties` Records — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Externalized Config — `application.yml`, Property Precedence, `@Profile` & `@ConfigurationProperties` Records using @Validated @Configurat...
Externalized Config — `application.yml`, Property Precedence, `@Profile` & `@ConfigurationProperties` Records — Actuator, Logs & MockMvc Lab Task
import jakarta.validation.constraints.*;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.validation.annotation.Validated;
import java.time.Duration;
@Validated
@ConfigurationProperties(prefix = "academy.exam")
public record ExamProperties(
@Min(10) int questionsPerMock,
@NotNull Duration timeLimit
) {}💡 Self-Explanatory Overview: In simple, everyday terms, Embedded Server Tuning — `server.port`, Random Test Ports (`0`), Graceful Shutdown & Compression teaches you how Springboot applications configuring `server.port` (CLI `--server.port=9090`, `SERVER_PORT`, or `server.port=0` for OS-assigned random free port in integration tests!), `server.shutdown=graceful` (draining in-flight requests on `SIGTERM`!), and HTTP Gzip/Zstd response compression. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Embedded Server Tuning — `server.port`, Random Test Ports (`0`), Graceful Shutdown & Compression in real Springboot systems — specifically: Configuring `server.port` (CLI `--server.port=9090`, `SERVER_PORT`, or `server.port=0` for OS-assigned random free port in integration tests!), `server.shutdown=graceful` (draining in-flight requests on `SIGTERM`!), and HTTP Gzip/Zstd response compression, so your code stays reliable, fast, and easy to maintain in production.
The Spring Boot framework provides the default embedded server (Tomcat) to run the Spring Boot application. It runs on port 8080. It is possible to change the port in Spring Boot. We can change the port in Spring Boot by using the following interfaces and properties files: Using application.properties file Using application.yml file Using EmbeddedServletContainerCustomizer Interface Using WebServerFactoryCustomizer I...
Embedded Server Tuning — `server.port`, Random Test Ports (`0`), Graceful Shutdown & Compression — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Embedded Server Tuning — `server.port`, Random Test Ports (`0`), Graceful Shutdown & Compression using server.port=8080 | server.shutdown=...
Embedded Server Tuning — `server.port`, Random Test Ports (`0`), Graceful Shutdown & Compression — Actuator, Logs & MockMvc Lab Task
import org.springframework.boot.web.server.Shutdown;
import org.springframework.boot.web.server.WebServerFactoryCustomizer;
import org.springframework.boot.web.servlet.server.ConfigurableServletWebServerFactory;
WebServerFactoryCustomizer<ConfigurableServletWebServerFactory> serverTuner =
factory -> { factory.setPort(8085); factory.setShutdown(Shutdown.GRACEFUL); };Create an immutable `@Validated @ConfigurationProperties(prefix = "academy.payment") record PaymentProps(...)` failing fast at startup if API timeouts or URLs are invalid, paired with `@Profile("dev")` MockGateway and `@Profile("prod")` LiveGateway beans.
Module Learning & Hands-On Objectives
💡 Self-Explanatory Overview: In simple, everyday terms, `spring-boot-starter-web` — Embedded Tomcat, Jackson `ObjectMapper` & MVC Auto-Wiring teaches you how Springboot applications what `spring-boot-starter-web` auto-configures: Embedded Apache Tomcat (`8080`), `DispatcherServlet` mapped to `/`, `MappingJackson2HttpMessageConverter` (`ObjectMapper` + `JavaTimeModule`), static asset serving, and `MultipartResolver`. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply `spring-boot-starter-web` — Embedded Tomcat, Jackson `ObjectMapper` & MVC Auto-Wiring in real Springboot systems — specifically: What `spring-boot-starter-web` auto-configures: Embedded Apache Tomcat (`8080`), `DispatcherServlet` mapped to `/`, `MappingJackson2HttpMessageConverter` (`ObjectMapper` + `JavaTimeModule`), static asset serving, and `MultipartResolver`, so your code stays reliable, fast, and easy to maintain in production.
Spring Boot Starter Web is one of the most commonly used starter dependencies in Spring Boot. It helps developers quickly create web applications and RESTful services with minimal configuration. By adding a single dependency, Spring Boot automatically configures the required libraries and web server for the application. The following are the main features of spring-boot-starter-web: Supports web application developme...
`spring-boot-starter-web` — Embedded Tomcat, Jackson `ObjectMapper` & MVC Auto-Wiring — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating `spring-boot-starter-web` — Embedded Tomcat, Jackson `ObjectMapper` & MVC Auto-Wiring using spring-boot-starter-web -> Tomcat + Dispatcher...
`spring-boot-starter-web` — Embedded Tomcat, Jackson `ObjectMapper` & MVC Auto-Wiring — Actuator, Logs & MockMvc Lab Task
import org.springframework.web.bind.annotation.*;
import java.time.LocalDate;
record HealthBanner(String service, int offerFee, LocalDate date) {}
@RestController
@RequestMapping("/api/v1/meta")
public class MetaController {
@GetMapping("/banner")
public HealthBanner banner() {
return new HealthBanner("Springboot Training", 999, LocalDate.of(2026, 11, 1));
}
}💡 Self-Explanatory Overview: In simple, everyday terms, `DispatcherServlet` Front Controller Lifecycle — `HandlerMapping`, `HandlerInterceptor` & Message Converters teaches you how Springboot applications step-by-step HTTP request pipeline: Filter Chain -> **`DispatcherServlet`** -> `RequestMappingHandlerMapping` -> `HandlerInterceptor.preHandle()` -> `RequestMappingHandlerAdapter` (resolving `@PathVariable`/`@RequestBody`) -> Controller -> `HttpMessageConverter` JSON response!. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply `DispatcherServlet` Front Controller Lifecycle — `HandlerMapping`, `HandlerInterceptor` & Message Converters in real Springboot systems — specifically: Step-by-step HTTP request pipeline: Filter Chain -> **`DispatcherServlet`** -> `RequestMappingHandlerMapping` -> `HandlerInterceptor.preHandle()` -> `RequestMappingHandlerAdapter` (resolving `@PathVariable`/`@RequestBody`) -> Controller -> `HttpMessageConverter` JSON response!, so your code stays reliable, fast, and easy to maintain in production.
Spring Boot provides many built-in features that reduce manual configuration and simplify web application development. Two important concepts behind Spring Boot web applications are Auto Configuration and Dispatcher Servlet. In this chapter, we will understand how Spring Boot automatically configures web applications, how the Dispatcher Servlet handles requests, how Java objects are converted to JSON responses, and h...
`DispatcherServlet` Front Controller Lifecycle — `HandlerMapping`, `HandlerInterceptor` & Message Converters — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating `DispatcherServlet` Front Controller Lifecycle — `HandlerMapping`, `HandlerInterceptor` & Message Converters using DispatcherServlet -> Re...
`DispatcherServlet` Front Controller Lifecycle — `HandlerMapping`, `HandlerInterceptor` & Message Converters — Actuator, Logs & MockMvc Lab Task
import jakarta.servlet.http.*;
import org.springframework.web.servlet.HandlerInterceptor;
public class TraceInterceptor implements HandlerInterceptor {
@Override
public boolean preHandle(HttpServletRequest req, HttpServletResponse res, Object handler) {
res.setHeader("X-Academy-Track", "SPBT");
return true;
}
}💡 Self-Explanatory Overview: In simple, everyday terms, Routing & Parameter Binding — `@PathVariable`, `@RequestParam`, `@RequestHeader` & `ResponseEntity<T>` teaches you how Springboot applications clean URI path variables (`/courses/{slug}`) vs optional query filters (`@RequestParam(defaultValue = "0") int page`), explicit parameter names (`-parameters` compiler flag in Boot 3!), and full status/header control with `ResponseEntity<T>`. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Routing & Parameter Binding — `@PathVariable`, `@RequestParam`, `@RequestHeader` & `ResponseEntity<T>` in real Springboot systems — specifically: Clean URI path variables (`/courses/{slug}`) vs optional query filters (`@RequestParam(defaultValue = "0") int page`), explicit parameter names (`-parameters` compiler flag in Boot 3!), and full status/header control with `ResponseEntity<T>`, so your code stays reliable, fast, and easy to maintain in production.
The @PathVariable annotation is used to extract the value from the URI. It is most suitable for the RESTful web service where the URL contains some value. Spring MVC allows us to use multiple @PathVariable annotations in the same method. A path variable is a critical part of creating rest resources. Steps For Enhancing the Hello World Service with a Path Variable The following steps demonstrate how to create a RESTfu...
Routing & Parameter Binding — `@PathVariable`, `@RequestParam`, `@RequestHeader` & `ResponseEntity<T>` — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Routing & Parameter Binding — `@PathVariable`, `@RequestParam`, `@RequestHeader` & `ResponseEntity<T>` using @GetMapping("/courses/{slug}"...
Routing & Parameter Binding — `@PathVariable`, `@RequestParam`, `@RequestHeader` & `ResponseEntity<T>` — Actuator, Logs & MockMvc Lab Task
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
@RestController
@RequestMapping("/api/v1/courses")
public class CourseQueryController {
@GetMapping("/{code}")
public ResponseEntity<String> find(@PathVariable("code") String code, @RequestParam(defaultValue = "20") int limit) {
int safeLimit = Math.min(Math.max(limit, 1), 100);
return ResponseEntity.ok(code.toUpperCase() + ":limit=" + safeLimit);
}
}💡 Self-Explanatory Overview: In simple, everyday terms, Resource Mutation — `@PostMapping` (`201 Created` + `Location`), `PUT` vs `PATCH` & `@DeleteMapping` (`204`) teaches you how Springboot applications deserializing JSON payloads with `@RequestBody`, building RFC-9110 `Location` headers via `ServletUriComponentsBuilder.fromCurrentRequest()`, understanding HTTP **Idempotency** (`GET`, `PUT`, `DELETE` are idempotent; `POST` is NOT!), and returning `204 No Content`. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Resource Mutation — `@PostMapping` (`201 Created` + `Location`), `PUT` vs `PATCH` & `@DeleteMapping` (`204`) in real Springboot systems — specifically: Deserializing JSON payloads with `@RequestBody`, building RFC-9110 `Location` headers via `ServletUriComponentsBuilder.fromCurrentRequest()`, understanding HTTP **Idempotency** (`GET`, `PUT`, `DELETE` are idempotent; `POST` is NOT!), and returning `204 No Content`, so your code stays reliable, fast, and easy to maintain in production.
In the previous few steps, we have created simple RESTful services. In this section, we will use the POST method to post the user resource for the specific URI "/users." Here we are using two annotations, @RequestBody and @PathMapping. @RequestBody The @RequestBody annotation maps body of the web request to the method parameter. The body of the request is passed through an HttpMessageConverter. It resolves...
Resource Mutation — `@PostMapping` (`201 Created` + `Location`), `PUT` vs `PATCH` & `@DeleteMapping` (`204`) — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Resource Mutation — `@PostMapping` (`201 Created` + `Location`), `PUT` vs `PATCH` & `@DeleteMapping` (`204`) using URI location = ServletU...
Resource Mutation — `@PostMapping` (`201 Created` + `Location`), `PUT` vs `PATCH` & `@DeleteMapping` (`204`) — Actuator, Logs & MockMvc Lab Task
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.servlet.support.ServletUriComponentsBuilder;
import java.net.URI;
record CreateLeadReq(String name, String track) {}
record LeadCreatedRes(long id, String name, String track) {}
@RestController
@RequestMapping("/api/v1/leads")
public class LeadRestController {
@PostMapping
public ResponseEntity<LeadCreatedRes> create(@RequestBody CreateLeadReq req) {
LeadCreatedRes saved...Build an idiomatic `/api/v1/cohorts` REST controller returning `ResponseEntity<CohortDto>` with `ServletUriComponentsBuilder` `Location` headers on `POST`, `204 No Content` on `DELETE`, and cursor/pageable pagination on `GET`.
Module Learning & Hands-On Objectives
💡 Self-Explanatory Overview: In simple, everyday terms, Global Exception Handling — `@RestControllerAdvice`, `@ExceptionHandler` & RFC-9457 `ProblemDetail` teaches you how Springboot applications replacing scattered controller `try/catch` blocks with a single `@RestControllerAdvice` aspect, extending `ResponseEntityExceptionHandler`, and returning Spring Framework 6’s native **`ProblemDetail`** (`application/problem+json` RFC-9457 standard!). Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Global Exception Handling — `@RestControllerAdvice`, `@ExceptionHandler` & RFC-9457 `ProblemDetail` in real Springboot systems — specifically: Replacing scattered controller `try/catch` blocks with a single `@RestControllerAdvice` aspect, extending `ResponseEntityExceptionHandler`, and returning Spring Framework 6’s native **`ProblemDetail`** (`application/problem+json` RFC-9457 standard!), so your code stays reliable, fast, and easy to maintain in production.
In RESTful web services, it is a good practice to return exceptions in a consistent format across all APIs. Generic exception handling helps centralize exception management and ensures that all controllers return standardized error responses. In this chapter, we will learn how to implement generic exception handling in Spring Boot and create a common exception response structure for all RESTful resources. Creating a...
Global Exception Handling — `@RestControllerAdvice`, `@ExceptionHandler` & RFC-9457 `ProblemDetail` — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Global Exception Handling — `@RestControllerAdvice`, `@ExceptionHandler` & RFC-9457 `ProblemDetail` using @RestControllerAdvice + @Excepti...
Global Exception Handling — `@RestControllerAdvice`, `@ExceptionHandler` & RFC-9457 `ProblemDetail` — Actuator, Logs & MockMvc Lab Task
import org.springframework.http.*;
import org.springframework.web.bind.annotation.*;
import java.net.URI;
class CourseNotFoundException extends RuntimeException {
CourseNotFoundException(String slug) { super("Course not found: " + slug); }
}
@RestControllerAdvice
public class GlobalApiExceptionHandler {
@ExceptionHandler(CourseNotFoundException.class)
public ProblemDetail handleNotFound(CourseNotFoundException ex) {
ProblemDetail pd = ProblemDetail.forStatusAndDetail(HttpStatus.NOT_FOUND, ex.g...💡 Self-Explanatory Overview: In simple, everyday terms, Jakarta Bean Validation (`spring-boot-starter-validation`) — `@Valid`, Nested DTOs & Custom Validators teaches you how Springboot applications note that Spring Boot 2.3+ extracted Hibernate Validator into explicit **`spring-boot-starter-validation`**! Enforcing `@NotBlank`, `@Email`, `@Size`, `@Positive`, cascading `@Valid` on nested objects/lists, and `@Validated` for method/query parameters. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Jakarta Bean Validation (`spring-boot-starter-validation`) — `@Valid`, Nested DTOs & Custom Validators in real Springboot systems — specifically: Note that Spring Boot 2.3+ extracted Hibernate Validator into explicit **`spring-boot-starter-validation`**! Enforcing `@NotBlank`, `@Email`, `@Size`, `@Positive`, cascading `@Valid` on nested objects/lists, and `@Validated` for method/query parameters, so your code stays reliable, fast, and easy to maintain in production.
Validation is an essential part of RESTful web services. It helps ensure that the data received from clients is correct and follows the required rules before it is processed and stored by the application. In this chapter, we will learn how to implement request validation in Spring Boot using the Java Validation API and how to return meaningful error responses when validation fails. Adding Validation to RESTful Servic...
Jakarta Bean Validation (`spring-boot-starter-validation`) — `@Valid`, Nested DTOs & Custom Validators — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Jakarta Bean Validation (`spring-boot-starter-validation`) — `@Valid`, Nested DTOs & Custom Validators using spring-boot-starter-validatio...
Jakarta Bean Validation (`spring-boot-starter-validation`) — `@Valid`, Nested DTOs & Custom Validators — Actuator, Logs & MockMvc Lab Task
import jakarta.validation.Valid;
import jakarta.validation.constraints.*;
public record EnrollRequest(
@NotBlank(message = "Student name is required") String studentName,
@Email(message = "Valid email required") String email,
@Min(value = 999, message = "Minimum cohort fee is 999") int feePaid
) {}💡 Self-Explanatory Overview: In simple, everyday terms, DTO Projections, Static (`@JsonIgnore`) & Dynamic (`MappingJacksonValue`) Filtering + Content Negotiation teaches you how Springboot applications preventing sensitive field exposure (`passwordHash`, `internalMargin`) and Mass-Assignment attacks (`role = "ADMIN"`): dedicated Request/Response Java `record` DTOs, `@JsonProperty(access = WRITE_ONLY)`, `@JsonView`, `MappingJacksonValue` `SimpleBeanPropertyFilter`, and XML/JSON Content Negotiation. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply DTO Projections, Static (`@JsonIgnore`) & Dynamic (`MappingJacksonValue`) Filtering + Content Negotiation in real Springboot systems — specifically: Preventing sensitive field exposure (`passwordHash`, `internalMargin`) and Mass-Assignment attacks (`role = "ADMIN"`): dedicated Request/Response Java `record` DTOs, `@JsonProperty(access = WRITE_ONLY)`, `@JsonView`, `MappingJacksonValue` `SimpleBeanPropertyFilter`, and XML/JSON Content Negotiation, so your code stays reliable, fast, and easy to maintain in production.
In the previous section, we have performed static filtering. Now we are moving to dynamic filtering. In the dynamic filtering, we define different filters for different services, according to need. So there exists the concept of dynamic filtering. Suppose there are three fields: name, phone, and salary. We want to send two fields: name and salary for the first service and name and phone for the second service. But th...
DTO Projections, Static (`@JsonIgnore`) & Dynamic (`MappingJacksonValue`) Filtering + Content Negotiation — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating DTO Projections, Static (`@JsonIgnore`) & Dynamic (`MappingJacksonValue`) Filtering + Content Negotiation using Dedicated Java record DTOs...
DTO Projections, Static (`@JsonIgnore`) & Dynamic (`MappingJacksonValue`) Filtering + Content Negotiation — Actuator, Logs & MockMvc Lab Task
import com.fasterxml.jackson.annotation.JsonIgnore;
public record StudentAccountView(
String studentCode,
String fullName,
@JsonIgnore String bcryptHash
) {}💡 Self-Explanatory Overview: In simple, everyday terms, REST API Versioning Strategies, `Spring HATEOAS` (`EntityModel`) & Internationalization (`i18n`) teaches you how Springboot applications four industry API versioning patterns (**URI Path** `/api/v1/users`, **Custom Header** `X-API-VERSION=1`, **Media-Type Accept** `application/vnd.company.v1+json`, **Query Param**), hypermedia links with `spring-boot-starter-hateoas` (`WebMvcLinkBuilder`), and `Accept-Language` `MessageSource` `i18n`. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply REST API Versioning Strategies, `Spring HATEOAS` (`EntityModel`) & Internationalization (`i18n`) in real Springboot systems — specifically: Four industry API versioning patterns (**URI Path** `/api/v1/users`, **Custom Header** `X-API-VERSION=1`, **Media-Type Accept** `application/vnd.company.v1+json`, **Query Param**), hypermedia links with `spring-boot-starter-hateoas` (`WebMvcLinkBuilder`), and `Accept-Language` `MessageSource` `i18n`, so your code stays reliable, fast, and easy to maintain in production.
Versioning is the most important and difficult part of the API as it takes backward API compatible. Versioning helps us to iterate faster when the changes are identified. We should always version our Web API. Consider a scenario in which we have a Web API that is up (status) and running. The users are consuming that API. Now we want to add more functionality in the Web API but want to keep the existing functionality...
REST API Versioning Strategies, `Spring HATEOAS` (`EntityModel`) & Internationalization (`i18n`) — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating REST API Versioning Strategies, `Spring HATEOAS` (`EntityModel`) & Internationalization (`i18n`) using URI (/api/v1/...) vs Header (header...
REST API Versioning Strategies, `Spring HATEOAS` (`EntityModel`) & Internationalization (`i18n`) — Actuator, Logs & MockMvc Lab Task
import org.springframework.web.bind.annotation.*;
@RestController
@RequestMapping("/api/courses")
public class VersionedCourseController {
@GetMapping(headers = "X-API-VERSION=1")
public String v1() { return "v1: Springboot Training - Rs.1,999"; }
@GetMapping(headers = "X-API-VERSION=2")
public String v2() { return "v2: {\"title\":\"Springboot Training\",\"offerInr\":999}"; }
}Implement a global `@RestControllerAdvice` mapping `ResourceNotFoundException` (`404`), `MethodArgumentNotValidException` (`400` with per-field violation map), and `DataIntegrityViolationException` (`409 Conflict`) into RFC-9457 `ProblemDetail` payloads without leaking stack traces.
Module Learning & Hands-On Objectives
💡 Self-Explanatory Overview: In simple, everyday terms, Spring AOP Architecture — CGLIB Subclass Proxies, JoinPoints, Pointcuts & Self-Invocation Trap teaches you how Springboot applications core AOP vocabulary (**Aspect**, **JoinPoint**, **Advice**, **Pointcut**, **Weaving**), why Spring Boot 2+/3+ defaults to **CGLIB** class-based runtime proxies (`spring.aop.proxy-target-class=true`), and how `@Transactional`, `@Cacheable`, and `@PreAuthorize` are ALL powered by Spring AOP!. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Spring AOP Architecture — CGLIB Subclass Proxies, JoinPoints, Pointcuts & Self-Invocation Trap in real Springboot systems — specifically: Core AOP vocabulary (**Aspect**, **JoinPoint**, **Advice**, **Pointcut**, **Weaving**), why Spring Boot 2+/3+ defaults to **CGLIB** class-based runtime proxies (`spring.aop.proxy-target-class=true`), and how `@Transactional`, `@Cacheable`, and `@PreAuthorize` are ALL powered by Spring AOP!, so your code stays reliable, fast, and easy to maintain in production.
The application is generally developed with multiple layers. A typical Java application has the following layers: Web Layer: It exposes the services using the REST or web application. Business Layer: It implements the business logic of an application. Data Layer: It implements the persistence logic of the application. The responsibility of each layer is different, but there are a few common aspects that apply to all...
Spring AOP Architecture — CGLIB Subclass Proxies, JoinPoints, Pointcuts & Self-Invocation Trap — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Spring AOP Architecture — CGLIB Subclass Proxies, JoinPoints, Pointcuts & Self-Invocation Trap using spring-boot-starter-aop -> @Aspect +...
Spring AOP Architecture — CGLIB Subclass Proxies, JoinPoints, Pointcuts & Self-Invocation Trap — Actuator, Logs & MockMvc Lab Task
// When PaymentService has an @Transactional or @Aspect advice:
// paymentService.getClass().getName() -> "com.mockattempt.PaymentService$$SpringCGLIB$$0"
String sampleProxyName = "PaymentService$$SpringCGLIB$$0";
System.out.println("Is CGLIB Proxy: " + sampleProxyName.contains("$$SpringCGLIB$$"));💡 Self-Explanatory Overview: In simple, everyday terms, `@Before`, `@After`, `@AfterReturning` & `@AfterThrowing` — Security, Audit & Failure Logging Advices teaches you how Springboot applications choosing the right advice lifecycle: **`@Before`** (pre-check / argument audit via `JoinPoint.getArgs()`), **`@AfterReturning`** (inspect return value when successful), **`@AfterThrowing`** (alert on unhandled exceptions without swallowing them!), and **`@After`** (`finally` cleanup). Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply `@Before`, `@After`, `@AfterReturning` & `@AfterThrowing` — Security, Audit & Failure Logging Advices in real Springboot systems — specifically: Choosing the right advice lifecycle: **`@Before`** (pre-check / argument audit via `JoinPoint.getArgs()`), **`@AfterReturning`** (inspect return value when successful), **`@AfterThrowing`** (alert on unhandled exceptions without swallowing them!), and **`@After`** (`finally` cleanup), so your code stays reliable, fast, and easy to maintain in production.
Before Advice is used in Aspect-Oriented Programming (AOP) to implement cross-cutting concerns such as logging, security, and transaction management. It is an advice type that executes before the target method is invoked. In Spring Boot, the @Before annotation is used to implement Before Advice. In this chapter, we will understand Spring Boot AOP Before Advice with the help of an example. Steps to Create Spring Boot...
`@Before`, `@After`, `@AfterReturning` & `@AfterThrowing` — Security, Audit & Failure Logging Advices — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating `@Before`, `@After`, `@AfterReturning` & `@AfterThrowing` — Security, Audit & Failure Logging Advices using @Before("@annotation(Audited)"...
`@Before`, `@After`, `@AfterReturning` & `@AfterThrowing` — Security, Audit & Failure Logging Advices — Actuator, Logs & MockMvc Lab Task
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.*;
import org.springframework.stereotype.Component;
@Aspect
@Component
public class EnrollmentAuditAspect {
@AfterReturning(pointcut = "execution(* com.mockattempt..*Service.enroll*(..))", returning = "receiptId")
public void onEnrolled(JoinPoint jp, Object receiptId) {
System.out.println("AUDIT [" + jp.getSignature().getName() + "] -> receipt=" + receiptId);
}
}💡 Self-Explanatory Overview: In simple, everyday terms, `@Around` Advice with `ProceedingJoinPoint` — SLA Latency Profiling & Idempotent Retry Interceptors teaches you how Springboot applications the most powerful AOP advice: `@Around` wraps target execution completely, decides whether/how many times to call `pjp.proceed()`, measures nanoTime SLA latency in `try/finally`, and binds Micrometer `Timer` metrics. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply `@Around` Advice with `ProceedingJoinPoint` — SLA Latency Profiling & Idempotent Retry Interceptors in real Springboot systems — specifically: The most powerful AOP advice: `@Around` wraps target execution completely, decides whether/how many times to call `pjp.proceed()`, measures nanoTime SLA latency in `try/finally`, and binds Micrometer `Timer` metrics, so your code stays reliable, fast, and easy to maintain in production.
Around Advice is represented by the @Around annotation in Aspect-Oriented Programming (AOP). It executes both before and after the execution of a method. It is considered the most powerful type of advice because it provides complete control over method execution using ProceedingJoinPoint. In this chapter, we will implement Around Advice in a Spring Boot application. Steps to Create Spring Boot AOP Around Advice Step...
`@Around` Advice with `ProceedingJoinPoint` — SLA Latency Profiling & Idempotent Retry Interceptors — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating `@Around` Advice with `ProceedingJoinPoint` — SLA Latency Profiling & Idempotent Retry Interceptors using @Around("@annotation(TimedOp)")...
`@Around` Advice with `ProceedingJoinPoint` — SLA Latency Profiling & Idempotent Retry Interceptors — Actuator, Logs & MockMvc Lab Task
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.*;
import org.springframework.stereotype.Component;
@Aspect
@Component
public class SlaTimerAspect {
@Around("@annotation(org.springframework.web.bind.annotation.GetMapping)")
public Object timeEndpoint(ProceedingJoinPoint pjp) throws Throwable {
long startNs = System.nanoTime();
try {
return pjp.proceed();
} finally {
long ms = (System.nanoTime() - startNs) / 1_000_000;...Create a custom `@Target(ElementType.METHOD) @Retention(RetentionPolicy.RUNTIME) @interface TrackLatency` annotation and an `@Aspect` using `@Around` (`ProceedingJoinPoint`) that logs method duration, tags slow calls (> 250 ms), and records outcome status in a `try/finally` block.
Module Learning & Hands-On Objectives
💡 Self-Explanatory Overview: In simple, everyday terms, Spring JDBC & `HikariCP` — Connection Pool Sizing & Modern `JdbcClient` / `JdbcTemplate` teaches you how Springboot applications why Spring Boot defaults to **`HikariCP`** (fastest zero-overhead JDBC pool on the JVM), pool sizing formula (`connections = (core_count * 2) + effective_spindle_count`), and Spring Boot 3.2+ fluent **`JdbcClient`** mapping directly to Java `record`s (`DataClassRowMapper`). Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Spring JDBC & `HikariCP` — Connection Pool Sizing & Modern `JdbcClient` / `JdbcTemplate` in real Springboot systems — specifically: Why Spring Boot defaults to **`HikariCP`** (fastest zero-overhead JDBC pool on the JVM), pool sizing formula (`connections = (core_count * 2) + effective_spindle_count`), and Spring Boot 3.2+ fluent **`JdbcClient`** mapping directly to Java `record`s (`DataClassRowMapper`), so your code stays reliable, fast, and easy to maintain in production.
Spring Boot JDBC provides starter and libraries for connecting an application with JDBC. In Spring Boot JDBC, the database related beans such as DataSource, JdbcTemplate, and NamedParameterJdbcTemplate auto-configures and created during the startup. We can autowire these classes if we want to use it. For example: Spring Boot Code / Configuration Example @Autowired JdbcTemplate jdbcTemplate; @Autowired private NamedPa...
Spring JDBC & `HikariCP` — Connection Pool Sizing & Modern `JdbcClient` / `JdbcTemplate` — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Spring JDBC & `HikariCP` — Connection Pool Sizing & Modern `JdbcClient` / `JdbcTemplate` using jdbcClient.sql("SELECT code, title, fee FRO...
Spring JDBC & `HikariCP` — Connection Pool Sizing & Modern `JdbcClient` / `JdbcTemplate` — Actuator, Logs & MockMvc Lab Task
import org.springframework.jdbc.core.simple.JdbcClient;
import java.util.Optional;
record CourseRow(String code, int fee) {}
class CourseJdbcDao {
private final JdbcClient jdbc;
CourseJdbcDao(JdbcClient jdbc) { this.jdbc = jdbc; }
Optional<CourseRow> byCode(String code) {
return jdbc.sql("SELECT code, fee FROM courses WHERE code = :code")
.param("code", code).query(CourseRow.class).optional();
}
}💡 Self-Explanatory Overview: In simple, everyday terms, Embedded H2 Database & Schema Migrations — Dev Prototyping vs Production `Flyway` / `Liquibase` teaches you how Springboot applications running zero-install `jdbc:h2:mem:academydb` in `dev` profile (`spring.h2.console.enabled=true`), initializing `schema.sql`/`data.sql` (`defer-datasource-initialization`), and why production MUST use **`Flyway`** or **`Liquibase`** with `ddl-auto: validate`!. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Embedded H2 Database & Schema Migrations — Dev Prototyping vs Production `Flyway` / `Liquibase` in real Springboot systems — specifically: Running zero-install `jdbc:h2:mem:academydb` in `dev` profile (`spring.h2.console.enabled=true`), initializing `schema.sql`/`data.sql` (`defer-datasource-initialization`), and why production MUST use **`Flyway`** or **`Liquibase`** with `ddl-auto: validate`!, so your code stays reliable, fast, and easy to maintain in production.
What is the in-memory database In-memory database relies on system memory as oppose to disk space for storage of data. Because memory access is faster than disk access. We use the in-memory database when we do not need to persist the data. The in-memory database is an embedded database. The in-memory databases are volatile, by default, and all stored data loss when we restart the application. The widely used in-memor...
Embedded H2 Database & Schema Migrations — Dev Prototyping vs Production `Flyway` / `Liquibase` — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Embedded H2 Database & Schema Migrations — Dev Prototyping vs Production `Flyway` / `Liquibase` using spring.datasource.url=jdbc:h2:mem:te...
Embedded H2 Database & Schema Migrations — Dev Prototyping vs Production `Flyway` / `Liquibase` — Actuator, Logs & MockMvc Lab Task
record DbSafetyAudit(String ddlAuto, boolean h2ConsoleEnabled) {
boolean isProductionSafe() {
return "validate".equals(ddlAuto) && !h2ConsoleEnabled;
}
}
// Audit check: new DbSafetyAudit("validate", false).isProductionSafe() -> true💡 Self-Explanatory Overview: In simple, everyday terms, `Spring Data JPA` & Hibernate 6 — `@Entity`, `JpaRepository`, `@Query`, Pagination & `@Transactional` teaches you how Springboot applications jPA Persistence Context (1st-level cache) & Automatic Dirty Checking, `JpaRepository<T, ID>`, derived query methods, custom JPQL `@Query`, `Page<T>` vs `Slice<T>` (`Slice` skips the expensive `SELECT COUNT(*)`!), and `@Transactional(readOnly = true)` optimizations. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply `Spring Data JPA` & Hibernate 6 — `@Entity`, `JpaRepository`, `@Query`, Pagination & `@Transactional` in real Springboot systems — specifically: JPA Persistence Context (1st-level cache) & Automatic Dirty Checking, `JpaRepository<T, ID>`, derived query methods, custom JPQL `@Query`, `Page<T>` vs `Slice<T>` (`Slice` skips the expensive `SELECT COUNT(*)`!), and `@Transactional(readOnly = true)` optimizations, so your code stays reliable, fast, and easy to maintain in production.
Spring Data is a high-level Spring Source project. Its purpose is to unify and easy access to the different kinds of persistence stores, both relational database systems, and NoSQL data stores. When we implement a new application, we should focus on the business logic instead of technical complexity and boilerplate code. That's why the Java Persistent API (JPA) specification and Spring Data JPA are extremely pop...
`Spring Data JPA` & Hibernate 6 — `@Entity`, `JpaRepository`, `@Query`, Pagination & `@Transactional` — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating `Spring Data JPA` & Hibernate 6 — `@Entity`, `JpaRepository`, `@Query`, Pagination & `@Transactional` using interface CourseRepository ext...
`Spring Data JPA` & Hibernate 6 — `@Entity`, `JpaRepository`, `@Query`, Pagination & `@Transactional` — Actuator, Logs & MockMvc Lab Task
import jakarta.persistence.*;
import org.springframework.data.domain.*;
import org.springframework.data.jpa.repository.*;
@Entity @Table(name = "courses")
class CourseEntity {
@Id @GeneratedValue(strategy = GenerationType.IDENTITY) Long id;
@Column(nullable = false, unique = true) String code;
int offerFee;
@Version Long version;
}
interface CourseRepo extends JpaRepository<CourseEntity, Long> {
Slice<CourseEntity> findByOfferFeeLessThanEqual(int maxFee, Pageable pageable);
}💡 Self-Explanatory Overview: In simple, everyday terms, JPA Entity Relationships (`@ManyToOne`, `@OneToMany`) — `FetchType.LAZY` & Crushing the `N+1` Trap teaches you how Springboot applications bidirectional mapping (`@OneToMany(mappedBy = "course")` + `@ManyToOne(fetch = FetchType.LAZY)` `@JoinColumn` owning side!), why JPA’s default `EAGER` on `@ManyToOne` / `@OneToOne` is a silent performance killer, and solving **`N+1` queries** via `@EntityGraph`, `JOIN FETCH`, or DTO Projections. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply JPA Entity Relationships (`@ManyToOne`, `@OneToMany`) — `FetchType.LAZY` & Crushing the `N+1` Trap in real Springboot systems — specifically: Bidirectional mapping (`@OneToMany(mappedBy = "course")` + `@ManyToOne(fetch = FetchType.LAZY)` `@JoinColumn` owning side!), why JPA’s default `EAGER` on `@ManyToOne` / `@OneToOne` is a silent performance killer, and solving **`N+1` queries** via `@EntityGraph`, `JOIN FETCH`, or DTO Projections, so your code stays reliable, fast, and easy to maintain in production.
In Spring Data JPA, entities can be connected through relationships such as one-to-one, one-to-many, many-to-one, and many-to-many. These relationships help represent real-world associations between database tables. In this chapter, we will learn how to create a Post entity and establish a many-to-one relationship between the Post and User entities using JPA annotations. Steps to Create a Post Entity and Configure th...
JPA Entity Relationships (`@ManyToOne`, `@OneToMany`) — `FetchType.LAZY` & Crushing the `N+1` Trap — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating JPA Entity Relationships (`@ManyToOne`, `@OneToMany`) — `FetchType.LAZY` & Crushing the `N+1` Trap using @ManyToOne(fetch = FetchType.LAZY...
JPA Entity Relationships (`@ManyToOne`, `@OneToMany`) — `FetchType.LAZY` & Crushing the `N+1` Trap — Actuator, Logs & MockMvc Lab Task
import jakarta.persistence.*;
import org.springframework.data.jpa.repository.*;
import java.util.List;
@Entity class BatchEntity {
@Id Long id;
String batchCode;
@ManyToOne(fetch = FetchType.LAZY) @JoinColumn(name = "course_id")
CourseEntity course;
}
interface BatchRepo extends JpaRepository<BatchEntity, Long> {
@EntityGraph(attributePaths = {"course"})
List<BatchEntity> findAll(); // Single LEFT JOIN SQL instead of N+1!
}Model `Course` (1) <-> (N) `CohortBatch` entities with explicit `FetchType.LAZY` on `@ManyToOne`, fetch paginated DTO summaries in 1 SQL query via JPQL Constructor/Record Projection, disable `spring.jpa.open-in-view=false`, and protect seat decrements against lost updates using `@Version` optimistic locking.
Module Learning & Hands-On Objectives
💡 Self-Explanatory Overview: In simple, everyday terms, Spring Cache Abstraction — `@EnableCaching`, `@Cacheable(sync = true)`, `@CachePut` & `@CacheEvict` teaches you how Springboot applications decoupling business logic from cache storage via `CacheManager`, SpEL cache keys (`key = "#courseCode"`), conditional caching (`condition` / `unless`), **`sync = true` Cache Stampede protection**, and cache invalidation on writes (`@CacheEvict`). Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Spring Cache Abstraction — `@EnableCaching`, `@Cacheable(sync = true)`, `@CachePut` & `@CacheEvict` in real Springboot systems — specifically: Decoupling business logic from cache storage via `CacheManager`, SpEL cache keys (`key = "#courseCode"`), conditional caching (`condition` / `unless`), **`sync = true` Cache Stampede protection**, and cache invalidation on writes (`@CacheEvict`), so your code stays reliable, fast, and easy to maintain in production.
Spring Framework provides caching in a Spring Application, transparently. In Spring, the cache abstraction is a mechanism that allows consistent use of various caching methods with minimal impact on the code. Cache Abstraction The cache abstraction mechanism applies to Java methods. The main objective of using cache abstraction is to reduce the number of executions based on the information present in the cache. It ap...
Spring Cache Abstraction — `@EnableCaching`, `@Cacheable(sync = true)`, `@CachePut` & `@CacheEvict` — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Spring Cache Abstraction — `@EnableCaching`, `@Cacheable(sync = true)`, `@CachePut` & `@CacheEvict` using @EnableCaching + @Cacheable(valu...
Spring Cache Abstraction — `@EnableCaching`, `@Cacheable(sync = true)`, `@CachePut` & `@CacheEvict` — Actuator, Logs & MockMvc Lab Task
import org.springframework.cache.annotation.*;
import org.springframework.stereotype.Service;
@Service
public class CachedCatalogService {
@Cacheable(cacheNames = "courses", key = "#slug", sync = true)
public String findCourse(String slug) {
return "DB_LOAD:" + slug.toUpperCase() + ":Rs.1,999";
}
@CacheEvict(cacheNames = "courses", key = "#slug")
public void refreshCourse(String slug) { /* Evicts stale entry */ }
}💡 Self-Explanatory Overview: In simple, everyday terms, Cache Providers (`Caffeine`, `EhCache 3`, `Redis`) — Local JVM Heap Speed vs Distributed Consistency teaches you how Springboot applications choosing the right backing store: **Caffeine** (Window-TinyLFU near-optimal hit rate in nanosecond JVM RAM), **EhCache 3** (`JCache` JSR-107 off-heap/disk tiers), and **Redis** (`spring-boot-starter-data-redis` shared across N Kubernetes pods with JSON serialization & jittered TTLs). Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Cache Providers (`Caffeine`, `EhCache 3`, `Redis`) — Local JVM Heap Speed vs Distributed Consistency in real Springboot systems — specifically: Choosing the right backing store: **Caffeine** (Window-TinyLFU near-optimal hit rate in nanosecond JVM RAM), **EhCache 3** (`JCache` JSR-107 off-heap/disk tiers), and **Redis** (`spring-boot-starter-data-redis` shared across N Kubernetes pods with JSON serialization & jittered TTLs), so your code stays reliable, fast, and easy to maintain in production.
EhCache EhCache is an open-source, Java-based cache used to boost performance. The current version of Ehcache is 3. It provides the implementation of the JSR-107 cache manager. We can use it directly. Features of EhCache It is fast, lightweight, Scalable, and Flexible. It allows us to perform Serializable and Object It offers cache eviction policies such as LRU, LFU, FIFO, It stores the cache in memory and disk (SSD)...
Cache Providers (`Caffeine`, `EhCache 3`, `Redis`) — Local JVM Heap Speed vs Distributed Consistency — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Cache Providers (`Caffeine`, `EhCache 3`, `Redis`) — Local JVM Heap Speed vs Distributed Consistency using spring.cache.type=caffeine | sp...
Cache Providers (`Caffeine`, `EhCache 3`, `Redis`) — Local JVM Heap Speed vs Distributed Consistency — Actuator, Logs & MockMvc Lab Task
// application.yml equivalent verification:
String caffeineSpec = "maximumSize=5000,expireAfterWrite=600s,recordStats";
boolean boundedAndTimed = caffeineSpec.contains("maximumSize=") && caffeineSpec.contains("expireAfterWrite=");
System.out.println("Caffeine Heap-Safe Spec Valid: " + boundedAndTimed);💡 Self-Explanatory Overview: In simple, everyday terms, Server-Side Rendering with `Thymeleaf` — Natural HTML5 Templates, `th:text` XSS Escaping & Emails teaches you how Springboot applications returning view names from `@Controller` (not `@RestController`!) backed by `src/main/resources/templates/*.html`, `Model.addAttribute()`, automatic HTML escaping with `th:text`, iteration (`th:each`), fragments, and rendering HTML PDFs / emails via `SpringTemplateEngine`. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Server-Side Rendering with `Thymeleaf` — Natural HTML5 Templates, `th:text` XSS Escaping & Emails in real Springboot systems — specifically: Returning view names from `@Controller` (not `@RestController`!) backed by `src/main/resources/templates/*.html`, `Model.addAttribute()`, automatic HTML escaping with `th:text`, iteration (`th:each`), fragments, and rendering HTML PDFs / emails via `SpringTemplateEngine`, so your code stays reliable, fast, and easy to maintain in production.
What is Thymeleaf? The Thymeleaf is an open-source Java library that is licensed under the Apache License 2.0. It is a HTML5/XHTML/XML template engine. It is a server-side Java template engine for both web (servlet-based) and non-web (offline) environments. It is perfect for modern-day HTML5 JVM web development. It provides full integration with Spring Framework. It applies a set of transformations to template files...
Server-Side Rendering with `Thymeleaf` — Natural HTML5 Templates, `th:text` XSS Escaping & Emails — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Server-Side Rendering with `Thymeleaf` — Natural HTML5 Templates, `th:text` XSS Escaping & Emails using @Controller + Model.addAttribute("...
Server-Side Rendering with `Thymeleaf` — Natural HTML5 Templates, `th:text` XSS Escaping & Emails — Actuator, Logs & MockMvc Lab Task
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
@Controller
public class CertificatePageController {
@GetMapping("/preview-card")
public String preview(Model model) {
model.addAttribute("trackTitle", "Springboot Training");
model.addAttribute("offerInr", 999);
return "course-card"; // Resolves classpath:/templates/course-card.html
}
}Configure `@EnableCaching` with `CaffeineCacheManager` (`maximumSize=1000, expireAfterWrite=10m`), guard hot course lookups with `@Cacheable(cacheNames = "courses", key = "#slug", sync = true)`, evict atomically on admin updates via `@CacheEvict`, and render a `Thymeleaf` HTML summary card.
Module Learning & Hands-On Objectives
💡 Self-Explanatory Overview: In simple, everyday terms, OpenAPI 3.1 & Swagger UI (`springdoc-openapi`) — `@Operation`, `@Schema` & Bearer JWT Docs teaches you how Springboot applications replacing deprecated `Springfox` (broken on Boot 3 `jakarta.*`!) with **`org.springdoc:springdoc-openapi-starter-webmvc-ui`**, auto-generating `/v3/api-docs` + `/swagger-ui.html` from Java `record` DTOs & Jakarta `@Valid` annotations, and gating Swagger UI in production. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply OpenAPI 3.1 & Swagger UI (`springdoc-openapi`) — `@Operation`, `@Schema` & Bearer JWT Docs in real Springboot systems — specifically: Replacing deprecated `Springfox` (broken on Boot 3 `jakarta.*`!) with **`org.springdoc:springdoc-openapi-starter-webmvc-ui`**, auto-generating `/v3/api-docs` + `/swagger-ui.html` from Java `record` DTOs & Jakarta `@Valid` annotations, and gating Swagger UI in production, so your code stays reliable, fast, and easy to maintain in production.
Swagger is an open-source framework used to design, document, and test RESTful APIs. It generates interactive API documentation automatically that makes it easier for developers and consumers to understand and use web services. In this chapter, we will learn how to configure Swagger in a Spring Boot application and automatically generate documentation for RESTful web services. What is Swagger? Swagger is a popular AP...
OpenAPI 3.1 & Swagger UI (`springdoc-openapi`) — `@Operation`, `@Schema` & Bearer JWT Docs — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating OpenAPI 3.1 & Swagger UI (`springdoc-openapi`) — `@Operation`, `@Schema` & Bearer JWT Docs using springdoc-openapi-starter-webmvc-ui + @Ta...
OpenAPI 3.1 & Swagger UI (`springdoc-openapi`) — `@Operation`, `@Schema` & Bearer JWT Docs — Actuator, Logs & MockMvc Lab Task
import io.swagger.v3.oas.annotations.Operation;
import io.swagger.v3.oas.annotations.responses.ApiResponse;
import org.springframework.web.bind.annotation.*;
@RestController
public class CatalogDocController {
@Operation(summary = "Fetch Springboot Training fee", description = "Returns affordable INR cohort pricing")
@ApiResponse(responseCode = "200", description = "Pricing retrieved")
@GetMapping("/api/v1/pricing/spbt")
public int pricing() { return 999; }
}💡 Self-Explanatory Overview: In simple, everyday terms, `Spring Security 6` Architecture — `SecurityFilterChain`, Lambda DSL, Stateless JWT, CORS & `@PreAuthorize` teaches you how Springboot applications how `DelegatingFilterProxy` -> `FilterChainProxy` -> **`SecurityFilterChain`** intercepts requests BEFORE `DispatcherServlet`! Spring Security 6 Lambda DSL (`http.csrf(...)`, `authorizeHttpRequests`), `BCryptPasswordEncoder`, OAuth2 / JWT Resource Server, and `@EnableMethodSecurity` (`@PreAuthorize`). Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply `Spring Security 6` Architecture — `SecurityFilterChain`, Lambda DSL, Stateless JWT, CORS & `@PreAuthorize` in real Springboot systems — specifically: How `DelegatingFilterProxy` -> `FilterChainProxy` -> **`SecurityFilterChain`** intercepts requests BEFORE `DispatcherServlet`! Spring Security 6 Lambda DSL (`http.csrf(...)`, `authorizeHttpRequests`), `BCryptPasswordEncoder`, OAuth2 / JWT Resource Server, and `@EnableMethodSecurity` (`@PreAuthorize`), so your code stays reliable, fast, and easy to maintain in production.
Basic Authentication is one of the simplest ways to secure RESTful web services. It requires users to provide a username and password before accessing protected resources. In this chapter, we will learn how to secure Spring Boot REST APIs using Spring Security and implement Basic Authentication for user access control. What is Basic Authentication? Basic Authentication is an HTTP authentication mechanism in which a c...
`Spring Security 6` Architecture — `SecurityFilterChain`, Lambda DSL, Stateless JWT, CORS & `@PreAuthorize` — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating `Spring Security 6` Architecture — `SecurityFilterChain`, Lambda DSL, Stateless JWT, CORS & `@PreAuthorize` using @Bean SecurityFilterChai...
`Spring Security 6` Architecture — `SecurityFilterChain`, Lambda DSL, Stateless JWT, CORS & `@PreAuthorize` — Actuator, Logs & MockMvc Lab Task
import org.springframework.context.annotation.*;
import org.springframework.security.config.annotation.method.configuration.EnableMethodSecurity;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.http.SessionCreationPolicy;
import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
import org.springframework.security.crypto.password.PasswordEncoder;
import org.springframework.security.web.SecurityFilterChain;
@Configuration
@En...💡 Self-Explanatory Overview: In simple, everyday terms, `Spring Boot Actuator` & Micrometer — Kubernetes Liveness/Readiness Probes, Custom `HealthIndicator` & Prometheus teaches you how Springboot applications production observability with `spring-boot-starter-actuator`: `/actuator/health/liveness` (restart deadlocked pod) vs `/actuator/health/readiness` (stop routing traffic while DB warms up), Micrometer dimensional metrics (`/actuator/prometheus`), and OpenTelemetry distributed tracing. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply `Spring Boot Actuator` & Micrometer — Kubernetes Liveness/Readiness Probes, Custom `HealthIndicator` & Prometheus in real Springboot systems — specifically: Production observability with `spring-boot-starter-actuator`: `/actuator/health/liveness` (restart deadlocked pod) vs `/actuator/health/readiness` (stop routing traffic while DB warms up), Micrometer dimensional metrics (`/actuator/prometheus`), and OpenTelemetry distributed tracing, so your code stays reliable, fast, and easy to maintain in production.
Spring Boot Actuator Spring Boot Actuator is a sub-project of the Spring Boot Framework. It includes a number of additional features that help us to monitor and manage the Spring Boot application. It contains the actuator endpoints (the place where the resources live). We can use HTTP and JMX endpoints to manage and monitor the Spring Boot application. If we want to get production-ready features in an application, we...
`Spring Boot Actuator` & Micrometer — Kubernetes Liveness/Readiness Probes, Custom `HealthIndicator` & Prometheus — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating `Spring Boot Actuator` & Micrometer — Kubernetes Liveness/Readiness Probes, Custom `HealthIndicator` & Prometheus using management.endpoin...
`Spring Boot Actuator` & Micrometer — Kubernetes Liveness/Readiness Probes, Custom `HealthIndicator` & Prometheus — Actuator, Logs & MockMvc Lab Task
import org.springframework.boot.actuate.health.*;
import org.springframework.stereotype.Component;
@Component("mockEngine")
public class MockEngineHealthIndicator implements HealthIndicator {
@Override
public Health health() {
return Health.up().withDetail("mcqsLoaded", 17500).withDetail("geminiVoiceReady", true).build();
}
}Configure a `SecurityFilterChain` bean permitting `/api/v1/public/**` and `/actuator/health/**`, requiring `ROLE_ADMIN` via `@PreAuthorize("hasRole('ADMIN')")` on curriculum mutations, hashing credentials with `BCryptPasswordEncoder(12)`, and documenting Bearer JWT auth in `springdoc-openapi`.
Module Learning & Hands-On Objectives
💡 Self-Explanatory Overview: In simple, everyday terms, Spring Boot Testing Pyramid — `JUnit 5`, `Mockito`, `@WebMvcTest` (`MockMvc`), `@DataJpaTest` & `@SpringBootTest` teaches you how Springboot applications what `spring-boot-starter-test` bundles (`JUnit Jupiter 5`, `Mockito`, `AssertJ`, `Hamcrest`, `JsonPath`, `MockMvc`), why **Slice Annotations** (`@WebMvcTest` loads ONLY web layer; `@DataJpaTest` loads ONLY JPA + transactional rollback!) beat heavy `@SpringBootTest` overuse, and Boot 3.4 `@MockitoBean`. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Spring Boot Testing Pyramid — `JUnit 5`, `Mockito`, `@WebMvcTest` (`MockMvc`), `@DataJpaTest` & `@SpringBootTest` in real Springboot systems — specifically: What `spring-boot-starter-test` bundles (`JUnit Jupiter 5`, `Mockito`, `AssertJ`, `Hamcrest`, `JsonPath`, `MockMvc`), why **Slice Annotations** (`@WebMvcTest` loads ONLY web layer; `@DataJpaTest` loads ONLY JPA + transactional rollback!) beat heavy `@SpringBootTest` overuse, and Boot 3.4 `@MockitoBean`, so your code stays reliable, fast, and easy to maintain in production.
Spring Boot provides the spring-boot-starter-test dependency for testing Spring Boot applications. It contains most of the libraries and tools required for unit testing, integration testing, and web testing. This starter simplifies the testing process by automatically including commonly used testing frameworks. Before performing any testing, we need to add the testing dependency to the Spring Boot project. Spring Boo...
Spring Boot Testing Pyramid — `JUnit 5`, `Mockito`, `@WebMvcTest` (`MockMvc`), `@DataJpaTest` & `@SpringBootTest` — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Spring Boot Testing Pyramid — `JUnit 5`, `Mockito`, `@WebMvcTest` (`MockMvc`), `@DataJpaTest` & `@SpringBootTest` using @ExtendWith(Mockit...
Spring Boot Testing Pyramid — `JUnit 5`, `Mockito`, `@WebMvcTest` (`MockMvc`), `@DataJpaTest` & `@SpringBootTest` — Actuator, Logs & MockMvc Lab Task
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
import org.springframework.test.web.servlet.MockMvc;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.*;
@WebMvcTest(MetaController.class)
class MetaControllerSliceTest {
@Autowired MockMvc mockMvc;
@Test
void banne...💡 Self-Explanatory Overview: In simple, everyday terms, Richardson Maturity Model (Levels 0–3) & Production Cloud-Native Spring Boot Best Practices teaches you how Springboot applications evaluating API maturity via the **Richardson Maturity Model** (Level 0: Swamp of POX single URI -> Level 1: Resource URIs -> Level 2: HTTP Verbs + Status Codes -> Level 3: HATEOAS Hypermedia Controls), Bucket4j / Redis Rate Limiting (`429 Too Many Requests`), Timeouts on `RestClient`, and Structured JSON Logging (`spring.logging.structured.format.console=ecs` in Boot 3.4!). Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Richardson Maturity Model (Levels 0–3) & Production Cloud-Native Spring Boot Best Practices in real Springboot systems — specifically: Evaluating API maturity via the **Richardson Maturity Model** (Level 0: Swamp of POX single URI -> Level 1: Resource URIs -> Level 2: HTTP Verbs + Status Codes -> Level 3: HATEOAS Hypermedia Controls), Bucket4j / Redis Rate Limiting (`429 Too Many Requests`), Timeouts on `RestClient`, and Structured JSON Logging (`spring.logging.structured.format.console=ecs` in Boot 3.4!), so your code stays reliable, fast, and easy to maintain in production.
Following best practices helps in designing RESTful web services that are easy to understand, maintain, secure, and use. Well-designed APIs provide a better experience for both developers and consumers. In this chapter, we will learn the commonly recommended best practices for designing and developing RESTful web services. Consumer First Approach The most important principle when designing a REST API is to think from...
Richardson Maturity Model (Levels 0–3) & Production Cloud-Native Spring Boot Best Practices — Spring Boot Practical Assignment
Build a clean Java 21 + Spring Boot 3 component demonstrating Richardson Maturity Model (Levels 0–3) & Production Cloud-Native Spring Boot Best Practices using Richardson Level 2/3 + RestClient with e...
Richardson Maturity Model (Levels 0–3) & Production Cloud-Native Spring Boot Best Practices — Actuator, Logs & MockMvc Lab Task
import org.springframework.http.client.SimpleClientHttpRequestFactory;
import org.springframework.web.client.RestClient;
import java.time.Duration;
public class ResilientGatewayClient {
public static RestClient create(String baseUrl) {
SimpleClientHttpRequestFactory rf = new SimpleClientHttpRequestFactory();
rf.setConnectTimeout(Duration.ofSeconds(2));
rf.setReadTimeout(Duration.ofSeconds(3));
return RestClient.builder().baseUrl(baseUrl).requestFactory(rf).build();
}
}Write a 3-tier automated test suite for the Enrollment Service: (1) pure `@ExtendWith(MockitoExtension.class)` unit test verifying business rules in 5 ms, (2) `@WebMvcTest` `MockMvc` slice test asserting `201 Created` + `400 ProblemDetail`, and (3) `@DataJpaTest` verifying custom repository queries.
Module Learning & Hands-On Objectives
💡 Self-Explanatory Overview: In simple, everyday terms, Modern Lambda SecurityFilterChain, CORS & Password Encoders teaches you how Springboot applications secure REST endpoints cleanly with Argon2/BCrypt and structured ProblemDetail 401/403s. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Modern Lambda SecurityFilterChain, CORS & Password Encoders in real Springboot systems — specifically: Secure REST endpoints cleanly with Argon2/BCrypt and structured ProblemDetail 401/403s, so your code stays reliable, fast, and easy to maintain in production.
What Is Modern Lambda SecurityFilterChain, CORS & Password Encoders & Why Industry Teams Use ItIn Springboot Training, Modern Lambda SecurityFilterChain, CORS & Password Encoders exists for one clear real-world purpose: Secure REST endpoints cleanly with Argon2/BCrypt and structured ProblemDetail 401/403s. Even if you come from a non-technical background, we start with the everyday real-life problem first...
Hands-On Implementation: Modern Lambda SecurityFilterChain, CORS & Password Encoders
Build and verify a clean working module demonstrating Modern Lambda SecurityFilterChain, CORS & Password Encoders (Secure REST endpoints cleanly with Argon2/BCrypt and structured ProblemDetail 401/403...
Live Lab Sprint: Modern Lambda SecurityFilterChain, CORS & Password Encoders
// Modern Lambda SecurityFilterChain, CORS & Password Encoders
// Purpose: Secure REST endpoints cleanly with Argon2/BCrypt and structured ProblemDetail 401/403s.
public record VerificationResult(boolean ok, String detail) {
public static VerificationResult verify(String input) {
if (input == null || input.isBlank()) throw new IllegalArgumentException("Missing input");
return new VerificationResult(true, input.trim());
}
}💡 Self-Explanatory Overview: In simple, everyday terms, RSA JWT Issuance, Refresh Token Rotation & OAuth2 Resource Server teaches you how Springboot applications verify signed claims and tenant IDs across endpoints with zero session memory bloat. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply RSA JWT Issuance, Refresh Token Rotation & OAuth2 Resource Server in real Springboot systems — specifically: Verify signed claims and tenant IDs across endpoints with zero session memory bloat, so your code stays reliable, fast, and easy to maintain in production.
What Is RSA JWT Issuance, Refresh Token Rotation & OAuth2 Resource Server & Why Industry Teams Use ItIn Springboot Training, RSA JWT Issuance, Refresh Token Rotation & OAuth2 Resource Server exists for one clear real-world purpose: Verify signed claims and tenant IDs across endpoints with zero session memory bloat. Even if you come from a non-technical background, we start with the everyday real-life prob...
Hands-On Implementation: RSA JWT Issuance, Refresh Token Rotation & OAuth2 Resource Server
Build and verify a clean working module demonstrating RSA JWT Issuance, Refresh Token Rotation & OAuth2 Resource Server (Verify signed claims and tenant IDs across endpoints with zero session memory b...
Live Lab Sprint: RSA JWT Issuance, Refresh Token Rotation & OAuth2 Resource Server
// RSA JWT Issuance, Refresh Token Rotation & OAuth2 Resource Server
// Purpose: Verify signed claims and tenant IDs across endpoints with zero session memory bloat.
public record VerificationResult(boolean ok, String detail) {
public static VerificationResult verify(String input) {
if (input == null || input.isBlank()) throw new IllegalArgumentException("Missing input");
return new VerificationResult(true, input.trim());
}
}💡 Self-Explanatory Overview: In simple, everyday terms, @PreAuthorize Method RBAC & Security Audit Listeners teaches you how Springboot applications enforce fine-grained ownership checks directly on business service methods. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply @PreAuthorize Method RBAC & Security Audit Listeners in real Springboot systems — specifically: Enforce fine-grained ownership checks directly on business service methods, so your code stays reliable, fast, and easy to maintain in production.
What Is @PreAuthorize Method RBAC & Security Audit Listeners & Why Industry Teams Use ItIn Springboot Training, @PreAuthorize Method RBAC & Security Audit Listeners exists for one clear real-world purpose: Enforce fine-grained ownership checks directly on business service methods. Even if you come from a non-technical background, we start with the everyday real-life problem first before writing production...
Hands-On Implementation: @PreAuthorize Method RBAC & Security Audit Listeners
Build and verify a clean working module demonstrating @PreAuthorize Method RBAC & Security Audit Listeners (Enforce fine-grained ownership checks directly on business service methods.). Handle invalid...
Live Lab Sprint: @PreAuthorize Method RBAC & Security Audit Listeners
// @PreAuthorize Method RBAC & Security Audit Listeners
// Purpose: Enforce fine-grained ownership checks directly on business service methods.
public record VerificationResult(boolean ok, String detail) {
public static VerificationResult verify(String input) {
if (input == null || input.isBlank()) throw new IllegalArgumentException("Missing input");
return new VerificationResult(true, input.trim());
}
}Design, implement, test, and document 'Stateless JWT + Role-Scoped Enterprise Spring Boot API' applying every production concept from Module 11 (Spring Security 6 FilterChains, OAuth2/JWT & Method Authorization) of Springboot Training.
Module Learning & Hands-On Objectives
💡 Self-Explanatory Overview: In simple, everyday terms, Eliminating N+1 Queries via @EntityGraph, JOIN FETCH & Record DTOs teaches you how Springboot applications slash 150 lazy-loading SQL queries down to 1 indexed projection query. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Eliminating N+1 Queries via @EntityGraph, JOIN FETCH & Record DTOs in real Springboot systems — specifically: Slash 150 lazy-loading SQL queries down to 1 indexed projection query, so your code stays reliable, fast, and easy to maintain in production.
What Is Eliminating N+1 Queries via @EntityGraph, JOIN FETCH & Record DTOs & Why Industry Teams Use ItIn Springboot Training, Eliminating N+1 Queries via @EntityGraph, JOIN FETCH & Record DTOs exists for one clear real-world purpose: Slash 150 lazy-loading SQL queries down to 1 indexed projection query. Even if you come from a non-technical background, we start with the everyday real-life problem first be...
Hands-On Implementation: Eliminating N+1 Queries via @EntityGraph, JOIN FETCH & Record DTOs
Build and verify a clean working module demonstrating Eliminating N+1 Queries via @EntityGraph, JOIN FETCH & Record DTOs (Slash 150 lazy-loading SQL queries down to 1 indexed projection query.). Handl...
Live Lab Sprint: Eliminating N+1 Queries via @EntityGraph, JOIN FETCH & Record DTOs
// Eliminating N+1 Queries via @EntityGraph, JOIN FETCH & Record DTOs
// Purpose: Slash 150 lazy-loading SQL queries down to 1 indexed projection query.
public record VerificationResult(boolean ok, String detail) {
public static VerificationResult verify(String input) {
if (input == null || input.isBlank()) throw new IllegalArgumentException("Missing input");
return new VerificationResult(true, input.trim());
}
}💡 Self-Explanatory Overview: In simple, everyday terms, Optimistic Locking (@Version), HikariCP Tuning & Flyway SQL Migrations teaches you how Springboot applications prevent concurrent lost updates and version every schema change reproducibly. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Optimistic Locking (@Version), HikariCP Tuning & Flyway SQL Migrations in real Springboot systems — specifically: Prevent concurrent lost updates and version every schema change reproducibly, so your code stays reliable, fast, and easy to maintain in production.
What Is Optimistic Locking (@Version), HikariCP Tuning & Flyway SQL Migrations & Why Industry Teams Use ItIn Springboot Training, Optimistic Locking (@Version), HikariCP Tuning & Flyway SQL Migrations exists for one clear real-world purpose: Prevent concurrent lost updates and version every schema change reproducibly. Even if you come from a non-technical background, we start with the everyday real-life p...
Hands-On Implementation: Optimistic Locking (@Version), HikariCP Tuning & Flyway SQL Migrations
Build and verify a clean working module demonstrating Optimistic Locking (@Version), HikariCP Tuning & Flyway SQL Migrations (Prevent concurrent lost updates and version every schema change reproducib...
Live Lab Sprint: Optimistic Locking (@Version), HikariCP Tuning & Flyway SQL Migrations
// Optimistic Locking (@Version), HikariCP Tuning & Flyway SQL Migrations
// Purpose: Prevent concurrent lost updates and version every schema change reproducibly.
public record VerificationResult(boolean ok, String detail) {
public static VerificationResult verify(String input) {
if (input == null || input.isBlank()) throw new IllegalArgumentException("Missing input");
return new VerificationResult(true, input.trim());
}
}💡 Self-Explanatory Overview: In simple, everyday terms, Spring @Cacheable with Redis TTLs & Targeted Eviction teaches you how Springboot applications serve hot reference and catalog endpoints in < 4ms under peak concurrency. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Spring @Cacheable with Redis TTLs & Targeted Eviction in real Springboot systems — specifically: Serve hot reference and catalog endpoints in < 4ms under peak concurrency, so your code stays reliable, fast, and easy to maintain in production.
What Is Spring @Cacheable with Redis TTLs & Targeted Eviction & Why Industry Teams Use ItIn Springboot Training, Spring @Cacheable with Redis TTLs & Targeted Eviction exists for one clear real-world purpose: Serve hot reference and catalog endpoints in < 4ms under peak concurrency. Even if you come from a non-technical background, we start with the everyday real-life problem first before writing produc...
Hands-On Implementation: Spring @Cacheable with Redis TTLs & Targeted Eviction
Build and verify a clean working module demonstrating Spring @Cacheable with Redis TTLs & Targeted Eviction (Serve hot reference and catalog endpoints in < 4ms under peak concurrency.). Handle invalid...
Live Lab Sprint: Spring @Cacheable with Redis TTLs & Targeted Eviction
// Spring @Cacheable with Redis TTLs & Targeted Eviction
// Purpose: Serve hot reference and catalog endpoints in < 4ms under peak concurrency.
public record VerificationResult(boolean ok, String detail) {
public static VerificationResult verify(String input) {
if (input == null || input.isBlank()) throw new IllegalArgumentException("Missing input");
return new VerificationResult(true, input.trim());
}
}Design, implement, test, and document 'N+1-Free Order Engine with Flyway & Two-Tier Redis Cache' applying every production concept from Module 12 (Hibernate/JPA Performance, Flyway Migrations & Redis Caching) of Springboot Training.
Module Learning & Hands-On Objectives
💡 Self-Explanatory Overview: In simple, everyday terms, Spring Kafka Producers, Consumer Groups, Retries & Dead-Letter Topics teaches you how Springboot applications decouple slow invoice/notification pipelines from synchronous customer APIs. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Spring Kafka Producers, Consumer Groups, Retries & Dead-Letter Topics in real Springboot systems — specifically: Decouple slow invoice/notification pipelines from synchronous customer APIs, so your code stays reliable, fast, and easy to maintain in production.
What Is Spring Kafka Producers, Consumer Groups, Retries & Dead-Letter Topics & Why Industry Teams Use ItIn Springboot Training, Spring Kafka Producers, Consumer Groups, Retries & Dead-Letter Topics exists for one clear real-world purpose: Decouple slow invoice/notification pipelines from synchronous customer APIs. Even if you come from a non-technical background, we start with the everyday real-life prob...
Hands-On Implementation: Spring Kafka Producers, Consumer Groups, Retries & Dead-Letter Topics
Build and verify a clean working module demonstrating Spring Kafka Producers, Consumer Groups, Retries & Dead-Letter Topics (Decouple slow invoice/notification pipelines from synchronous customer APIs...
Live Lab Sprint: Spring Kafka Producers, Consumer Groups, Retries & Dead-Letter Topics
// Spring Kafka Producers, Consumer Groups, Retries & Dead-Letter Topics
// Purpose: Decouple slow invoice/notification pipelines from synchronous customer APIs.
public record VerificationResult(boolean ok, String detail) {
public static VerificationResult verify(String input) {
if (input == null || input.isBlank()) throw new IllegalArgumentException("Missing input");
return new VerificationResult(true, input.trim());
}
}💡 Self-Explanatory Overview: In simple, everyday terms, Resilience4j CircuitBreaker, Bulkhead & Exponential Backoff Retry teaches you how Springboot applications isolate degraded third-party gateways so upstream Spring threads never hang. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Resilience4j CircuitBreaker, Bulkhead & Exponential Backoff Retry in real Springboot systems — specifically: Isolate degraded third-party gateways so upstream Spring threads never hang, so your code stays reliable, fast, and easy to maintain in production.
What Is Resilience4j CircuitBreaker, Bulkhead & Exponential Backoff Retry & Why Industry Teams Use ItIn Springboot Training, Resilience4j CircuitBreaker, Bulkhead & Exponential Backoff Retry exists for one clear real-world purpose: Isolate degraded third-party gateways so upstream Spring threads never hang. Even if you come from a non-technical background, we start with the everyday real-life problem firs...
Hands-On Implementation: Resilience4j CircuitBreaker, Bulkhead & Exponential Backoff Retry
Build and verify a clean working module demonstrating Resilience4j CircuitBreaker, Bulkhead & Exponential Backoff Retry (Isolate degraded third-party gateways so upstream Spring threads never hang.)....
Live Lab Sprint: Resilience4j CircuitBreaker, Bulkhead & Exponential Backoff Retry
// Resilience4j CircuitBreaker, Bulkhead & Exponential Backoff Retry
// Purpose: Isolate degraded third-party gateways so upstream Spring threads never hang.
public record VerificationResult(boolean ok, String detail) {
public static VerificationResult verify(String input) {
if (input == null || input.isBlank()) throw new IllegalArgumentException("Missing input");
return new VerificationResult(true, input.trim());
}
}💡 Self-Explanatory Overview: In simple, everyday terms, Transactional Outbox & ShedLock Distributed Cron Jobs teaches you how Springboot applications guarantee reliable event publishing and single-pod execution across scaled replicas. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Transactional Outbox & ShedLock Distributed Cron Jobs in real Springboot systems — specifically: Guarantee reliable event publishing and single-pod execution across scaled replicas, so your code stays reliable, fast, and easy to maintain in production.
What Is Transactional Outbox & ShedLock Distributed Cron Jobs & Why Industry Teams Use ItIn Springboot Training, Transactional Outbox & ShedLock Distributed Cron Jobs exists for one clear real-world purpose: Guarantee reliable event publishing and single-pod execution across scaled replicas. Even if you come from a non-technical background, we start with the everyday real-life problem first before writing...
Hands-On Implementation: Transactional Outbox & ShedLock Distributed Cron Jobs
Build and verify a clean working module demonstrating Transactional Outbox & ShedLock Distributed Cron Jobs (Guarantee reliable event publishing and single-pod execution across scaled replicas.). Hand...
Live Lab Sprint: Transactional Outbox & ShedLock Distributed Cron Jobs
// Transactional Outbox & ShedLock Distributed Cron Jobs
// Purpose: Guarantee reliable event publishing and single-pod execution across scaled replicas.
public record VerificationResult(boolean ok, String detail) {
public static VerificationResult verify(String input) {
if (input == null || input.isBlank()) throw new IllegalArgumentException("Missing input");
return new VerificationResult(true, input.trim());
}
}Design, implement, test, and document 'Fault-Tolerant Event-Driven Billing Service with Circuit Breakers' applying every production concept from Module 13 (Async Messaging (Kafka/RabbitMQ), Resilience4j & Scheduled Locks) of Springboot Training.
Module Learning & Hands-On Objectives
💡 Self-Explanatory Overview: In simple, everyday terms, @WebMvcTest Slices, Mockito & @ServiceConnection Testcontainers teaches you how Springboot applications run automated integration tests against real PostgreSQL and Redis containers in CI. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply @WebMvcTest Slices, Mockito & @ServiceConnection Testcontainers in real Springboot systems — specifically: Run automated integration tests against real PostgreSQL and Redis containers in CI, so your code stays reliable, fast, and easy to maintain in production.
What Is @WebMvcTest Slices, Mockito & @ServiceConnection Testcontainers & Why Industry Teams Use ItIn Springboot Training, @WebMvcTest Slices, Mockito & @ServiceConnection Testcontainers exists for one clear real-world purpose: Run automated integration tests against real PostgreSQL and Redis containers in CI. Even if you come from a non-technical background, we start with the everyday real-life problem f...
Hands-On Implementation: @WebMvcTest Slices, Mockito & @ServiceConnection Testcontainers
Build and verify a clean working module demonstrating @WebMvcTest Slices, Mockito & @ServiceConnection Testcontainers (Run automated integration tests against real PostgreSQL and Redis containers in C...
Live Lab Sprint: @WebMvcTest Slices, Mockito & @ServiceConnection Testcontainers
// @WebMvcTest Slices, Mockito & @ServiceConnection Testcontainers
// Purpose: Run automated integration tests against real PostgreSQL and Redis containers in CI.
public record VerificationResult(boolean ok, String detail) {
public static VerificationResult verify(String input) {
if (input == null || input.isBlank()) throw new IllegalArgumentException("Missing input");
return new VerificationResult(true, input.trim());
}
}💡 Self-Explanatory Overview: In simple, everyday terms, Actuator Readiness/Liveness Probes, Micrometer Prometheus & Tracing teaches you how Springboot applications track p99 latency, JVM heap, Hikari pools, and trace IDs across every request. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Actuator Readiness/Liveness Probes, Micrometer Prometheus & Tracing in real Springboot systems — specifically: Track p99 latency, JVM heap, Hikari pools, and trace IDs across every request, so your code stays reliable, fast, and easy to maintain in production.
What Is Actuator Readiness/Liveness Probes, Micrometer Prometheus & Tracing & Why Industry Teams Use ItIn Springboot Training, Actuator Readiness/Liveness Probes, Micrometer Prometheus & Tracing exists for one clear real-world purpose: Track p99 latency, JVM heap, Hikari pools, and trace IDs across every request. Even if you come from a non-technical background, we start with the everyday real-life proble...
Hands-On Implementation: Actuator Readiness/Liveness Probes, Micrometer Prometheus & Tracing
Build and verify a clean working module demonstrating Actuator Readiness/Liveness Probes, Micrometer Prometheus & Tracing (Track p99 latency, JVM heap, Hikari pools, and trace IDs across every request...
Live Lab Sprint: Actuator Readiness/Liveness Probes, Micrometer Prometheus & Tracing
// Actuator Readiness/Liveness Probes, Micrometer Prometheus & Tracing
// Purpose: Track p99 latency, JVM heap, Hikari pools, and trace IDs across every request.
public record VerificationResult(boolean ok, String detail) {
public static VerificationResult verify(String input) {
if (input == null || input.isBlank()) throw new IllegalArgumentException("Missing input");
return new VerificationResult(true, input.trim());
}
}💡 Self-Explanatory Overview: In simple, everyday terms, Layered Spring Boot Dockerfiles, Virtual Threads & Graceful Shutdown teaches you how Springboot applications deploy fast-booting, zero-downtime Java 21 containers to cloud clusters. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Layered Spring Boot Dockerfiles, Virtual Threads & Graceful Shutdown in real Springboot systems — specifically: Deploy fast-booting, zero-downtime Java 21 containers to cloud clusters, so your code stays reliable, fast, and easy to maintain in production.
What Is Layered Spring Boot Dockerfiles, Virtual Threads & Graceful Shutdown & Why Industry Teams Use ItIn Springboot Training, Layered Spring Boot Dockerfiles, Virtual Threads & Graceful Shutdown exists for one clear real-world purpose: Deploy fast-booting, zero-downtime Java 21 containers to cloud clusters. Even if you come from a non-technical background, we start with the everyday real-life problem fi...
Hands-On Implementation: Layered Spring Boot Dockerfiles, Virtual Threads & Graceful Shutdown
Build and verify a clean working module demonstrating Layered Spring Boot Dockerfiles, Virtual Threads & Graceful Shutdown (Deploy fast-booting, zero-downtime Java 21 containers to cloud clusters.). H...
Live Lab Sprint: Layered Spring Boot Dockerfiles, Virtual Threads & Graceful Shutdown
// Layered Spring Boot Dockerfiles, Virtual Threads & Graceful Shutdown
// Purpose: Deploy fast-booting, zero-downtime Java 21 containers to cloud clusters.
public record VerificationResult(boolean ok, String detail) {
public static VerificationResult verify(String input) {
if (input == null || input.isBlank()) throw new IllegalArgumentException("Missing input");
return new VerificationResult(true, input.trim());
}
}Design, implement, test, and document 'Production-Ready Containerized Spring Boot 3 Release Pipeline' applying every production concept from Module 14 (Testcontainers CI Suites, OpenTelemetry Actuator & Docker/K8s Prod) of Springboot Training.
Module Learning & Hands-On Objectives
💡 Self-Explanatory Overview: In simple, everyday terms, RFC 7807 ProblemDetails Global Error Responses & Jakarta Bean Validation Groups teaches you how Springboot applications return standardized, client-friendly JSON error contracts across every REST controller. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply RFC 7807 ProblemDetails Global Error Responses & Jakarta Bean Validation Groups in real Springboot systems — specifically: Return standardized, client-friendly JSON error contracts across every REST controller, so your code stays reliable, fast, and easy to maintain in production.
Self-Explanatory Guide: RFC 7807 ProblemDetails Global Error Responses & Jakarta Bean Validation Groups (Plain-English & Industry Purpose)In simple, everyday terms, RFC 7807 ProblemDetails Global Error Responses & Jakarta Bean Validation Groups teaches you how Springboot applications return standardized, client-friendly JSON error contracts across every REST controller. Even if you have never seen this co...
Practical Implementation: RFC 7807 ProblemDetails Global Error Responses & Jakarta Bean Validation Groups
Implement and verify RFC 7807 ProblemDetails Global Error Responses & Jakarta Bean Validation Groups (Return standardized, client-friendly JSON error contracts across every REST controller) with expli...
Guided Live Lab Checklist: RFC 7807 ProblemDetails Global Error Responses & Jakarta Bean Validation Groups
// RFC 7807 ProblemDetails Global Error Responses & Jakarta Bean Validation Groups
// Purpose: Return standardized, client-friendly JSON error contracts across every REST controller
import java.util.Map;
public final class ProductionTopicCheck {
public static Map<String, Object> verify(String tenantId) {
if (tenantId == null || tenantId.isBlank()) {
throw new IllegalArgumentException("tenantId is required");
}
return Map.of("topic", "RFC 7807 ProblemDetails Global Error Resp...💡 Self-Explanatory Overview: In simple, everyday terms, Spring Cache Abstraction with Redis TTLs, Cache Stampede Prevention & Eviction teaches you how Springboot applications accelerate read-heavy catalog/profile endpoints while keeping cached entries fresh on updates. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Spring Cache Abstraction with Redis TTLs, Cache Stampede Prevention & Eviction in real Springboot systems — specifically: Accelerate read-heavy catalog/profile endpoints while keeping cached entries fresh on updates, so your code stays reliable, fast, and easy to maintain in production.
Self-Explanatory Guide: Spring Cache Abstraction with Redis TTLs, Cache Stampede Prevention & Eviction (Plain-English & Industry Purpose)In simple, everyday terms, Spring Cache Abstraction with Redis TTLs, Cache Stampede Prevention & Eviction teaches you how Springboot applications accelerate read-heavy catalog/profile endpoints while keeping cached entries fresh on updates. Even if you have never seen th...
Practical Implementation: Spring Cache Abstraction with Redis TTLs, Cache Stampede Prevention & Eviction
Implement and verify Spring Cache Abstraction with Redis TTLs, Cache Stampede Prevention & Eviction (Accelerate read-heavy catalog/profile endpoints while keeping cached entries fresh on updates) with...
Guided Live Lab Checklist: Spring Cache Abstraction with Redis TTLs, Cache Stampede Prevention & Eviction
// Spring Cache Abstraction with Redis TTLs, Cache Stampede Prevention & Eviction
// Purpose: Accelerate read-heavy catalog/profile endpoints while keeping cached entries fresh on updates
import java.util.Map;
public final class ProductionTopicCheck {
public static Map<String, Object> verify(String tenantId) {
if (tenantId == null || tenantId.isBlank()) {
throw new IllegalArgumentException("tenantId is required");
}
return Map.of("topic", "Spring Cache Abstraction with Redis...💡 Self-Explanatory Overview: In simple, everyday terms, Resilience4j Retries, TimeLimiters, Circuit Breakers & @TransactionalEventListener teaches you how Springboot applications isolate downstream service failures and trigger side effects only after DB transactions commit. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Resilience4j Retries, TimeLimiters, Circuit Breakers & @TransactionalEventListener in real Springboot systems — specifically: Isolate downstream service failures and trigger side effects only after DB transactions commit, so your code stays reliable, fast, and easy to maintain in production.
Self-Explanatory Guide: Resilience4j Retries, TimeLimiters, Circuit Breakers & @TransactionalEventListener (Plain-English & Industry Purpose)In simple, everyday terms, Resilience4j Retries, TimeLimiters, Circuit Breakers & @TransactionalEventListener teaches you how Springboot applications isolate downstream service failures and trigger side effects only after DB transactions commit. Even if you have neve...
Practical Implementation: Resilience4j Retries, TimeLimiters, Circuit Breakers & @TransactionalEventListener
Implement and verify Resilience4j Retries, TimeLimiters, Circuit Breakers & @TransactionalEventListener (Isolate downstream service failures and trigger side effects only after DB transactions commit)...
Guided Live Lab Checklist: Resilience4j Retries, TimeLimiters, Circuit Breakers & @TransactionalEventListener
// Resilience4j Retries, TimeLimiters, Circuit Breakers & @TransactionalEventListener
// Purpose: Isolate downstream service failures and trigger side effects only after DB transactions commit
import java.util.Map;
public final class ProductionTopicCheck {
public static Map<String, Object> verify(String tenantId) {
if (tenantId == null || tenantId.isBlank()) {
throw new IllegalArgumentException("tenantId is required");
}
return Map.of("topic", "Resilience4j Retries, TimeLimi...Architect, implement, test, and document 'Resilient Spring Boot 3 Order API with Redis Cache, Circuit Breakers & ProblemDetails' applying every bullet-wise engineering concept from Module 15 (Spring Boot 3 Production Resilience: Caching, Rate Limiting & Async Events) of Springboot Training.
Module Learning & Hands-On Objectives
💡 Self-Explanatory Overview: In simple, everyday terms, Slice Tests (@WebMvcTest, @DataJpaTest) & Real-DB Integration with Testcontainers teaches you how Springboot applications verify JPA queries, Flyway migrations, and security filters against a real containerized database. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Slice Tests (@WebMvcTest, @DataJpaTest) & Real-DB Integration with Testcontainers in real Springboot systems — specifically: Verify JPA queries, Flyway migrations, and security filters against a real containerized database, so your code stays reliable, fast, and easy to maintain in production.
Self-Explanatory Guide: Slice Tests (@WebMvcTest, @DataJpaTest) & Real-DB Integration with Testcontainers (Plain-English & Industry Purpose)In simple, everyday terms, Slice Tests (@WebMvcTest, @DataJpaTest) & Real-DB Integration with Testcontainers teaches you how Springboot applications verify JPA queries, Flyway migrations, and security filters against a real containerized database. Even if you have nev...
Practical Implementation: Slice Tests (@WebMvcTest, @DataJpaTest) & Real-DB Integration with Testcontainers
Implement and verify Slice Tests (@WebMvcTest, @DataJpaTest) & Real-DB Integration with Testcontainers (Verify JPA queries, Flyway migrations, and security filters against a real containerized databas...
Guided Live Lab Checklist: Slice Tests (@WebMvcTest, @DataJpaTest) & Real-DB Integration with Testcontainers
// Slice Tests (@WebMvcTest, @DataJpaTest) & Real-DB Integration with Testcontainers
// Purpose: Verify JPA queries, Flyway migrations, and security filters against a real containerized database
import java.util.Map;
public final class ProductionTopicCheck {
public static Map<String, Object> verify(String tenantId) {
if (tenantId == null || tenantId.isBlank()) {
throw new IllegalArgumentException("tenantId is required");
}
return Map.of("topic", "Slice Tests (@WebMvcTest, @D...💡 Self-Explanatory Overview: In simple, everyday terms, Spring Boot Actuator, Micrometer Metrics & Distributed Trace Propagation teaches you how Springboot applications expose production health/readiness endpoints and latency histograms for cloud monitoring. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Spring Boot Actuator, Micrometer Metrics & Distributed Trace Propagation in real Springboot systems — specifically: Expose production health/readiness endpoints and latency histograms for cloud monitoring, so your code stays reliable, fast, and easy to maintain in production.
Self-Explanatory Guide: Spring Boot Actuator, Micrometer Metrics & Distributed Trace Propagation (Plain-English & Industry Purpose)In simple, everyday terms, Spring Boot Actuator, Micrometer Metrics & Distributed Trace Propagation teaches you how Springboot applications expose production health/readiness endpoints and latency histograms for cloud monitoring. Even if you have never seen this concept before...
Practical Implementation: Spring Boot Actuator, Micrometer Metrics & Distributed Trace Propagation
Implement and verify Spring Boot Actuator, Micrometer Metrics & Distributed Trace Propagation (Expose production health/readiness endpoints and latency histograms for cloud monitoring) with explicit i...
Guided Live Lab Checklist: Spring Boot Actuator, Micrometer Metrics & Distributed Trace Propagation
// Spring Boot Actuator, Micrometer Metrics & Distributed Trace Propagation
// Purpose: Expose production health/readiness endpoints and latency histograms for cloud monitoring
import java.util.Map;
public final class ProductionTopicCheck {
public static Map<String, Object> verify(String tenantId) {
if (tenantId == null || tenantId.isBlank()) {
throw new IllegalArgumentException("tenantId is required");
}
return Map.of("topic", "Spring Boot Actuator, Micrometer Metrics & Dis...💡 Self-Explanatory Overview: In simple, everyday terms, Spring IoC/Proxy Pitfalls, N+1 Query Fixes & Enterprise Interview Scenarios teaches you how Springboot applications spot @Transactional self-invocation bugs and Hibernate N+1 bottlenecks instantly. Even if you have never seen this concept before, your trainer explains the real-life problem first, writes clean Spring Boot 3.4, Java 21 Virtual Threads, Spring Web MVC & REST code live on screen, and shows what breaks in production if this step is skipped.
🎯 For What Purpose: To understand and apply Spring IoC/Proxy Pitfalls, N+1 Query Fixes & Enterprise Interview Scenarios in real Springboot systems — specifically: Spot @Transactional self-invocation bugs and Hibernate N+1 bottlenecks instantly, so your code stays reliable, fast, and easy to maintain in production.
Self-Explanatory Guide: Spring IoC/Proxy Pitfalls, N+1 Query Fixes & Enterprise Interview Scenarios (Plain-English & Industry Purpose)In simple, everyday terms, Spring IoC/Proxy Pitfalls, N+1 Query Fixes & Enterprise Interview Scenarios teaches you how Springboot applications spot @Transactional self-invocation bugs and Hibernate N+1 bottlenecks instantly. Even if you have never seen this concept before,...
Practical Implementation: Spring IoC/Proxy Pitfalls, N+1 Query Fixes & Enterprise Interview Scenarios
Implement and verify Spring IoC/Proxy Pitfalls, N+1 Query Fixes & Enterprise Interview Scenarios (Spot @Transactional self-invocation bugs and Hibernate N+1 bottlenecks instantly) with explicit input...
Guided Live Lab Checklist: Spring IoC/Proxy Pitfalls, N+1 Query Fixes & Enterprise Interview Scenarios
// Spring IoC/Proxy Pitfalls, N+1 Query Fixes & Enterprise Interview Scenarios
// Purpose: Spot @Transactional self-invocation bugs and Hibernate N+1 bottlenecks instantly
import java.util.Map;
public final class ProductionTopicCheck {
public static Map<String, Object> verify(String tenantId) {
if (tenantId == null || tenantId.isBlank()) {
throw new IllegalArgumentException("tenantId is required");
}
return Map.of("topic", "Spring IoC/Proxy Pitfalls, N+1 Query Fixes & Enterp...Architect, implement, test, and document 'Testcontainers PostgreSQL Suite + Actuator Prometheus/OpenTelemetry Stack' applying every bullet-wise engineering concept from Module 16 (Testcontainers Integration Suites, Micrometer Tracing & Spring Interviews) of Springboot Training.
For What Purpose: To understand and apply Spring Boot 3 Overview — Opinionated Defaults, Embedded Servers & Zero-XML Philosophy in real Springboot systems — specifically: How Spring Boot wraps the Spring IoC Container (`ApplicationContext`) with opinionated Starter dependencies, Conditional Auto-Configuration, an embedded Tomcat/Jetty/Undertow server, and production-ready Actuator metrics, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Spring Framework vs Spring MVC vs Spring Boot — IoC Container, `DispatcherServlet` & Auto-Setup in real Springboot systems — specifically: Clear architectural boundaries: **Spring Core** provides IoC & Dependency Injection; **Spring MVC** is the web module (`DispatcherServlet`, `@Controller`); **Spring Boot** auto-wires both with curated BOM versions and embedded servers, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Spring Boot 4-Layer Architecture — Presentation, Business Service, Persistence & Database Flow in real Springboot systems — specifically: Strict separation of concerns: **1. Presentation Layer** (`@RestController`, HTTP/DTO validation), **2. Service Layer** (`@Service`, business rules & `@Transactional` boundaries), **3. Persistence Layer** (`@Repository`, JPA/JDBC), and **4. Database**, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Core Spring Boot 3.4 Features — `SpringApplication`, `CommandLineRunner`, Profiles & Java 21 Virtual Threads in real Springboot systems — specifically: Customizing `SpringApplication` (`Banner.Mode`, `ApplicationRunner` / `CommandLineRunner` startup tasks, `ApplicationEvent` pub/sub), environment-specific `@Profile`, and enabling Project Loom **Java 21 Virtual Threads** with a single property!, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: Architect a 4-layer Spring Boot 3.4 service (`CourseController` -> `CourseService` -> `CourseRepository` -> immutable `CourseRecord`) using zero `@Autowired` field injection, `spring.threads.virtual.enabled=true`, and a `CommandLineRunner` seed verifier.
For What Purpose: To understand and apply `Spring Initializr` (`start.spring.io`) — Project Metadata, Maven Wrapper (`mvnw`) & Directory Layout in real Springboot systems — specifically: Generating standardized builds via `start.spring.io` (or IDE wizard / `curl https://start.spring.io/starter.zip`), why committing Maven Wrapper (`mvnw` / `mvnw.cmd`) guarantees reproducible CI builds, and root package placement rules, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Spring Boot Starters & `spring-boot-starter-parent` BOM Dependency Management in real Springboot systems — specifically: How opinionated `spring-boot-starter-*` poms (`starter-web`, `starter-data-jpa`, `starter-security`, `starter-test`) bundle cohesive transitive libraries while `spring-boot-dependencies` Bill of Materials (BOM) guarantees tested version compatibility, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Executable Fat JARs (`JarLauncher`, `BOOT-INF`) vs External Tomcat WAR Deployment in real Springboot systems — specifically: How `spring-boot-maven-plugin` (`repackage` goal) creates a self-contained **Executable Nested JAR** (`Main-Class: JarLauncher`, `Start-Class: YourApp`, `BOOT-INF/classes`, `BOOT-INF/lib`), Docker Layered JAR caching, and `SpringBootServletInitializer` for legacy WARs, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Spring Boot DevTools (`RestartClassLoader`), LiveReload & Rapid Local Iteration in real Springboot systems — specifically: How `spring-boot-devtools` uses a dual-ClassLoader trick (**Base ClassLoader** keeps immutable ` ~/.m2` JARs warm in memory; **RestartClassLoader** reloads ONLY your edited `target/classes` in ~300 ms!), disables template caches in dev, and turns itself OFF in packaged JARs, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: Configure a Java 21 `pom.xml` inheriting `spring-boot-starter-parent:3.4.x`, extract layered JAR segments (`dependencies`, `spring-boot-loader`, `application`) for fast 2-second Docker image rebuilds, and wire `spring-boot-devtools` strictly as `<optional>true</optional>`.
For What Purpose: To understand and apply Core Stereotype & DI Annotations — `@SpringBootApplication`, `@Service`, `@Bean`, `@Qualifier` & Scopes in real Springboot systems — specifically: The 3-in-1 `@SpringBootApplication` meta-annotation, `@Component` vs `@Service` vs `@Repository` (which adds `PersistenceExceptionTranslationPostProcessor`!), `@Configuration` (`proxyBeanMethods`) + `@Bean`, `@Primary` vs `@Qualifier`, and Singleton vs Prototype bean scopes, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Spring Boot 3 Auto-Configuration Internals — `AutoConfiguration.imports` & `@ConditionalOn*` Guards in real Springboot systems — specifically: How Spring Boot 3 moved from legacy `spring.factories` to **`META-INF/spring/org.springframework.boot.autoconfigure.AutoConfiguration.imports`**, evaluates `@ConditionalOnClass`, `@ConditionalOnMissingBean`, `@ConditionalOnProperty`, and prints the Positive/Negative match report via `--debug`, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Externalized Config — `application.yml`, Property Precedence, `@Profile` & `@ConfigurationProperties` Records in real Springboot systems — specifically: 12-Factor externalized configuration: `application.yml` vs `.properties`, OS Environment Variables (`SPRING_DATASOURCE_URL` relaxed binding!) overriding packaged files, profile-specific `application-prod.yml`, and validated `@ConfigurationProperties` Java 21 `record`s, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Embedded Server Tuning — `server.port`, Random Test Ports (`0`), Graceful Shutdown & Compression in real Springboot systems — specifically: Configuring `server.port` (CLI `--server.port=9090`, `SERVER_PORT`, or `server.port=0` for OS-assigned random free port in integration tests!), `server.shutdown=graceful` (draining in-flight requests on `SIGTERM`!), and HTTP Gzip/Zstd response compression, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: Create an immutable `@Validated @ConfigurationProperties(prefix = "academy.payment") record PaymentProps(...)` failing fast at startup if API timeouts or URLs are invalid, paired with `@Profile("dev")` MockGateway and `@Profile("prod")` LiveGateway beans.
For What Purpose: To understand and apply `spring-boot-starter-web` — Embedded Tomcat, Jackson `ObjectMapper` & MVC Auto-Wiring in real Springboot systems — specifically: What `spring-boot-starter-web` auto-configures: Embedded Apache Tomcat (`8080`), `DispatcherServlet` mapped to `/`, `MappingJackson2HttpMessageConverter` (`ObjectMapper` + `JavaTimeModule`), static asset serving, and `MultipartResolver`, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply `DispatcherServlet` Front Controller Lifecycle — `HandlerMapping`, `HandlerInterceptor` & Message Converters in real Springboot systems — specifically: Step-by-step HTTP request pipeline: Filter Chain -> **`DispatcherServlet`** -> `RequestMappingHandlerMapping` -> `HandlerInterceptor.preHandle()` -> `RequestMappingHandlerAdapter` (resolving `@PathVariable`/`@RequestBody`) -> Controller -> `HttpMessageConverter` JSON response!, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Routing & Parameter Binding — `@PathVariable`, `@RequestParam`, `@RequestHeader` & `ResponseEntity<T>` in real Springboot systems — specifically: Clean URI path variables (`/courses/{slug}`) vs optional query filters (`@RequestParam(defaultValue = "0") int page`), explicit parameter names (`-parameters` compiler flag in Boot 3!), and full status/header control with `ResponseEntity<T>`, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Resource Mutation — `@PostMapping` (`201 Created` + `Location`), `PUT` vs `PATCH` & `@DeleteMapping` (`204`) in real Springboot systems — specifically: Deserializing JSON payloads with `@RequestBody`, building RFC-9110 `Location` headers via `ServletUriComponentsBuilder.fromCurrentRequest()`, understanding HTTP **Idempotency** (`GET`, `PUT`, `DELETE` are idempotent; `POST` is NOT!), and returning `204 No Content`, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: Build an idiomatic `/api/v1/cohorts` REST controller returning `ResponseEntity<CohortDto>` with `ServletUriComponentsBuilder` `Location` headers on `POST`, `204 No Content` on `DELETE`, and cursor/pageable pagination on `GET`.
For What Purpose: To understand and apply Global Exception Handling — `@RestControllerAdvice`, `@ExceptionHandler` & RFC-9457 `ProblemDetail` in real Springboot systems — specifically: Replacing scattered controller `try/catch` blocks with a single `@RestControllerAdvice` aspect, extending `ResponseEntityExceptionHandler`, and returning Spring Framework 6’s native **`ProblemDetail`** (`application/problem+json` RFC-9457 standard!), so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Jakarta Bean Validation (`spring-boot-starter-validation`) — `@Valid`, Nested DTOs & Custom Validators in real Springboot systems — specifically: Note that Spring Boot 2.3+ extracted Hibernate Validator into explicit **`spring-boot-starter-validation`**! Enforcing `@NotBlank`, `@Email`, `@Size`, `@Positive`, cascading `@Valid` on nested objects/lists, and `@Validated` for method/query parameters, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply DTO Projections, Static (`@JsonIgnore`) & Dynamic (`MappingJacksonValue`) Filtering + Content Negotiation in real Springboot systems — specifically: Preventing sensitive field exposure (`passwordHash`, `internalMargin`) and Mass-Assignment attacks (`role = "ADMIN"`): dedicated Request/Response Java `record` DTOs, `@JsonProperty(access = WRITE_ONLY)`, `@JsonView`, `MappingJacksonValue` `SimpleBeanPropertyFilter`, and XML/JSON Content Negotiation, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply REST API Versioning Strategies, `Spring HATEOAS` (`EntityModel`) & Internationalization (`i18n`) in real Springboot systems — specifically: Four industry API versioning patterns (**URI Path** `/api/v1/users`, **Custom Header** `X-API-VERSION=1`, **Media-Type Accept** `application/vnd.company.v1+json`, **Query Param**), hypermedia links with `spring-boot-starter-hateoas` (`WebMvcLinkBuilder`), and `Accept-Language` `MessageSource` `i18n`, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: Implement a global `@RestControllerAdvice` mapping `ResourceNotFoundException` (`404`), `MethodArgumentNotValidException` (`400` with per-field violation map), and `DataIntegrityViolationException` (`409 Conflict`) into RFC-9457 `ProblemDetail` payloads without leaking stack traces.
For What Purpose: To understand and apply Spring AOP Architecture — CGLIB Subclass Proxies, JoinPoints, Pointcuts & Self-Invocation Trap in real Springboot systems — specifically: Core AOP vocabulary (**Aspect**, **JoinPoint**, **Advice**, **Pointcut**, **Weaving**), why Spring Boot 2+/3+ defaults to **CGLIB** class-based runtime proxies (`spring.aop.proxy-target-class=true`), and how `@Transactional`, `@Cacheable`, and `@PreAuthorize` are ALL powered by Spring AOP!, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply `@Before`, `@After`, `@AfterReturning` & `@AfterThrowing` — Security, Audit & Failure Logging Advices in real Springboot systems — specifically: Choosing the right advice lifecycle: **`@Before`** (pre-check / argument audit via `JoinPoint.getArgs()`), **`@AfterReturning`** (inspect return value when successful), **`@AfterThrowing`** (alert on unhandled exceptions without swallowing them!), and **`@After`** (`finally` cleanup), so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply `@Around` Advice with `ProceedingJoinPoint` — SLA Latency Profiling & Idempotent Retry Interceptors in real Springboot systems — specifically: The most powerful AOP advice: `@Around` wraps target execution completely, decides whether/how many times to call `pjp.proceed()`, measures nanoTime SLA latency in `try/finally`, and binds Micrometer `Timer` metrics, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: Create a custom `@Target(ElementType.METHOD) @Retention(RetentionPolicy.RUNTIME) @interface TrackLatency` annotation and an `@Aspect` using `@Around` (`ProceedingJoinPoint`) that logs method duration, tags slow calls (> 250 ms), and records outcome status in a `try/finally` block.
For What Purpose: To understand and apply Spring JDBC & `HikariCP` — Connection Pool Sizing & Modern `JdbcClient` / `JdbcTemplate` in real Springboot systems — specifically: Why Spring Boot defaults to **`HikariCP`** (fastest zero-overhead JDBC pool on the JVM), pool sizing formula (`connections = (core_count * 2) + effective_spindle_count`), and Spring Boot 3.2+ fluent **`JdbcClient`** mapping directly to Java `record`s (`DataClassRowMapper`), so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Embedded H2 Database & Schema Migrations — Dev Prototyping vs Production `Flyway` / `Liquibase` in real Springboot systems — specifically: Running zero-install `jdbc:h2:mem:academydb` in `dev` profile (`spring.h2.console.enabled=true`), initializing `schema.sql`/`data.sql` (`defer-datasource-initialization`), and why production MUST use **`Flyway`** or **`Liquibase`** with `ddl-auto: validate`!, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply `Spring Data JPA` & Hibernate 6 — `@Entity`, `JpaRepository`, `@Query`, Pagination & `@Transactional` in real Springboot systems — specifically: JPA Persistence Context (1st-level cache) & Automatic Dirty Checking, `JpaRepository<T, ID>`, derived query methods, custom JPQL `@Query`, `Page<T>` vs `Slice<T>` (`Slice` skips the expensive `SELECT COUNT(*)`!), and `@Transactional(readOnly = true)` optimizations, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply JPA Entity Relationships (`@ManyToOne`, `@OneToMany`) — `FetchType.LAZY` & Crushing the `N+1` Trap in real Springboot systems — specifically: Bidirectional mapping (`@OneToMany(mappedBy = "course")` + `@ManyToOne(fetch = FetchType.LAZY)` `@JoinColumn` owning side!), why JPA’s default `EAGER` on `@ManyToOne` / `@OneToOne` is a silent performance killer, and solving **`N+1` queries** via `@EntityGraph`, `JOIN FETCH`, or DTO Projections, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: Model `Course` (1) <-> (N) `CohortBatch` entities with explicit `FetchType.LAZY` on `@ManyToOne`, fetch paginated DTO summaries in 1 SQL query via JPQL Constructor/Record Projection, disable `spring.jpa.open-in-view=false`, and protect seat decrements against lost updates using `@Version` optimistic locking.
For What Purpose: To understand and apply Spring Cache Abstraction — `@EnableCaching`, `@Cacheable(sync = true)`, `@CachePut` & `@CacheEvict` in real Springboot systems — specifically: Decoupling business logic from cache storage via `CacheManager`, SpEL cache keys (`key = "#courseCode"`), conditional caching (`condition` / `unless`), **`sync = true` Cache Stampede protection**, and cache invalidation on writes (`@CacheEvict`), so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Cache Providers (`Caffeine`, `EhCache 3`, `Redis`) — Local JVM Heap Speed vs Distributed Consistency in real Springboot systems — specifically: Choosing the right backing store: **Caffeine** (Window-TinyLFU near-optimal hit rate in nanosecond JVM RAM), **EhCache 3** (`JCache` JSR-107 off-heap/disk tiers), and **Redis** (`spring-boot-starter-data-redis` shared across N Kubernetes pods with JSON serialization & jittered TTLs), so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Server-Side Rendering with `Thymeleaf` — Natural HTML5 Templates, `th:text` XSS Escaping & Emails in real Springboot systems — specifically: Returning view names from `@Controller` (not `@RestController`!) backed by `src/main/resources/templates/*.html`, `Model.addAttribute()`, automatic HTML escaping with `th:text`, iteration (`th:each`), fragments, and rendering HTML PDFs / emails via `SpringTemplateEngine`, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: Configure `@EnableCaching` with `CaffeineCacheManager` (`maximumSize=1000, expireAfterWrite=10m`), guard hot course lookups with `@Cacheable(cacheNames = "courses", key = "#slug", sync = true)`, evict atomically on admin updates via `@CacheEvict`, and render a `Thymeleaf` HTML summary card.
For What Purpose: To understand and apply OpenAPI 3.1 & Swagger UI (`springdoc-openapi`) — `@Operation`, `@Schema` & Bearer JWT Docs in real Springboot systems — specifically: Replacing deprecated `Springfox` (broken on Boot 3 `jakarta.*`!) with **`org.springdoc:springdoc-openapi-starter-webmvc-ui`**, auto-generating `/v3/api-docs` + `/swagger-ui.html` from Java `record` DTOs & Jakarta `@Valid` annotations, and gating Swagger UI in production, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply `Spring Security 6` Architecture — `SecurityFilterChain`, Lambda DSL, Stateless JWT, CORS & `@PreAuthorize` in real Springboot systems — specifically: How `DelegatingFilterProxy` -> `FilterChainProxy` -> **`SecurityFilterChain`** intercepts requests BEFORE `DispatcherServlet`! Spring Security 6 Lambda DSL (`http.csrf(...)`, `authorizeHttpRequests`), `BCryptPasswordEncoder`, OAuth2 / JWT Resource Server, and `@EnableMethodSecurity` (`@PreAuthorize`), so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply `Spring Boot Actuator` & Micrometer — Kubernetes Liveness/Readiness Probes, Custom `HealthIndicator` & Prometheus in real Springboot systems — specifically: Production observability with `spring-boot-starter-actuator`: `/actuator/health/liveness` (restart deadlocked pod) vs `/actuator/health/readiness` (stop routing traffic while DB warms up), Micrometer dimensional metrics (`/actuator/prometheus`), and OpenTelemetry distributed tracing, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: Configure a `SecurityFilterChain` bean permitting `/api/v1/public/**` and `/actuator/health/**`, requiring `ROLE_ADMIN` via `@PreAuthorize("hasRole('ADMIN')")` on curriculum mutations, hashing credentials with `BCryptPasswordEncoder(12)`, and documenting Bearer JWT auth in `springdoc-openapi`.
For What Purpose: To understand and apply Spring Boot Testing Pyramid — `JUnit 5`, `Mockito`, `@WebMvcTest` (`MockMvc`), `@DataJpaTest` & `@SpringBootTest` in real Springboot systems — specifically: What `spring-boot-starter-test` bundles (`JUnit Jupiter 5`, `Mockito`, `AssertJ`, `Hamcrest`, `JsonPath`, `MockMvc`), why **Slice Annotations** (`@WebMvcTest` loads ONLY web layer; `@DataJpaTest` loads ONLY JPA + transactional rollback!) beat heavy `@SpringBootTest` overuse, and Boot 3.4 `@MockitoBean`, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Richardson Maturity Model (Levels 0–3) & Production Cloud-Native Spring Boot Best Practices in real Springboot systems — specifically: Evaluating API maturity via the **Richardson Maturity Model** (Level 0: Swamp of POX single URI -> Level 1: Resource URIs -> Level 2: HTTP Verbs + Status Codes -> Level 3: HATEOAS Hypermedia Controls), Bucket4j / Redis Rate Limiting (`429 Too Many Requests`), Timeouts on `RestClient`, and Structured JSON Logging (`spring.logging.structured.format.console=ecs` in Boot 3.4!), so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: Write a 3-tier automated test suite for the Enrollment Service: (1) pure `@ExtendWith(MockitoExtension.class)` unit test verifying business rules in 5 ms, (2) `@WebMvcTest` `MockMvc` slice test asserting `201 Created` + `400 ProblemDetail`, and (3) `@DataJpaTest` verifying custom repository queries.
For What Purpose: To understand and apply Modern Lambda SecurityFilterChain, CORS & Password Encoders in real Springboot systems — specifically: Secure REST endpoints cleanly with Argon2/BCrypt and structured ProblemDetail 401/403s, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply RSA JWT Issuance, Refresh Token Rotation & OAuth2 Resource Server in real Springboot systems — specifically: Verify signed claims and tenant IDs across endpoints with zero session memory bloat, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply @PreAuthorize Method RBAC & Security Audit Listeners in real Springboot systems — specifically: Enforce fine-grained ownership checks directly on business service methods, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: Design, implement, test, and document 'Stateless JWT + Role-Scoped Enterprise Spring Boot API' applying every production concept from Module 11 (Spring Security 6 FilterChains, OAuth2/JWT & Method Authorization) of Springboot Training.
For What Purpose: To understand and apply Eliminating N+1 Queries via @EntityGraph, JOIN FETCH & Record DTOs in real Springboot systems — specifically: Slash 150 lazy-loading SQL queries down to 1 indexed projection query, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Optimistic Locking (@Version), HikariCP Tuning & Flyway SQL Migrations in real Springboot systems — specifically: Prevent concurrent lost updates and version every schema change reproducibly, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Spring @Cacheable with Redis TTLs & Targeted Eviction in real Springboot systems — specifically: Serve hot reference and catalog endpoints in < 4ms under peak concurrency, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: Design, implement, test, and document 'N+1-Free Order Engine with Flyway & Two-Tier Redis Cache' applying every production concept from Module 12 (Hibernate/JPA Performance, Flyway Migrations & Redis Caching) of Springboot Training.
For What Purpose: To understand and apply Spring Kafka Producers, Consumer Groups, Retries & Dead-Letter Topics in real Springboot systems — specifically: Decouple slow invoice/notification pipelines from synchronous customer APIs, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Resilience4j CircuitBreaker, Bulkhead & Exponential Backoff Retry in real Springboot systems — specifically: Isolate degraded third-party gateways so upstream Spring threads never hang, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Transactional Outbox & ShedLock Distributed Cron Jobs in real Springboot systems — specifically: Guarantee reliable event publishing and single-pod execution across scaled replicas, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: Design, implement, test, and document 'Fault-Tolerant Event-Driven Billing Service with Circuit Breakers' applying every production concept from Module 13 (Async Messaging (Kafka/RabbitMQ), Resilience4j & Scheduled Locks) of Springboot Training.
For What Purpose: To understand and apply @WebMvcTest Slices, Mockito & @ServiceConnection Testcontainers in real Springboot systems — specifically: Run automated integration tests against real PostgreSQL and Redis containers in CI, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Actuator Readiness/Liveness Probes, Micrometer Prometheus & Tracing in real Springboot systems — specifically: Track p99 latency, JVM heap, Hikari pools, and trace IDs across every request, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Layered Spring Boot Dockerfiles, Virtual Threads & Graceful Shutdown in real Springboot systems — specifically: Deploy fast-booting, zero-downtime Java 21 containers to cloud clusters, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: Design, implement, test, and document 'Production-Ready Containerized Spring Boot 3 Release Pipeline' applying every production concept from Module 14 (Testcontainers CI Suites, OpenTelemetry Actuator & Docker/K8s Prod) of Springboot Training.
For What Purpose: To understand and apply RFC 7807 ProblemDetails Global Error Responses & Jakarta Bean Validation Groups in real Springboot systems — specifically: Return standardized, client-friendly JSON error contracts across every REST controller, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Spring Cache Abstraction with Redis TTLs, Cache Stampede Prevention & Eviction in real Springboot systems — specifically: Accelerate read-heavy catalog/profile endpoints while keeping cached entries fresh on updates, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Resilience4j Retries, TimeLimiters, Circuit Breakers & @TransactionalEventListener in real Springboot systems — specifically: Isolate downstream service failures and trigger side effects only after DB transactions commit, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: Architect, implement, test, and document 'Resilient Spring Boot 3 Order API with Redis Cache, Circuit Breakers & ProblemDetails' applying every bullet-wise engineering concept from Module 15 (Spring Boot 3 Production Resilience: Caching, Rate Limiting & Async Events) of Springboot Training.
For What Purpose: To understand and apply Slice Tests (@WebMvcTest, @DataJpaTest) & Real-DB Integration with Testcontainers in real Springboot systems — specifically: Verify JPA queries, Flyway migrations, and security filters against a real containerized database, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Spring Boot Actuator, Micrometer Metrics & Distributed Trace Propagation in real Springboot systems — specifically: Expose production health/readiness endpoints and latency histograms for cloud monitoring, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: To understand and apply Spring IoC/Proxy Pitfalls, N+1 Query Fixes & Enterprise Interview Scenarios in real Springboot systems — specifically: Spot @Transactional self-invocation bugs and Hibernate N+1 bottlenecks instantly, so your code stays reliable, fast, and easy to maintain in production.
For What Purpose: Architect, implement, test, and document 'Testcontainers PostgreSQL Suite + Actuator Prometheus/OpenTelemetry Stack' applying every bullet-wise engineering concept from Module 16 (Testcontainers Integration Suites, Micrometer Tracing & Spring Interviews) of Springboot Training.
For What Purpose: Understand real client business requirements, production architecture (Java 21 + Spring Boot 3.3 + Spring Data JPA + Spring Security 6 JWT + PostgreSQL + Docker), and team Git branching.
For What Purpose: Build core client workflows, validation, and optimized database/state logic under Industry Expert mentorship.
For What Purpose: Eliminate vulnerabilities, race conditions, and regressions before exposing the system to real client traffic.
For What Purpose: Deploy the verified application to live cloud production with health checks, SSL/TLS, and uptime monitoring.
For What Purpose: Demonstrate your deployed client project, lock in resume/LinkedIn positioning, and receive dual recruiter-verifiable credentials.
Optional external proctored exams coached to ≥90% readiness: Official Vendor Exam Fee (Paid by Student) + Platform Charge (10% of Vendor Fee + 18% GST). Click any certificate card for full exam domains & blueprint details.
Broadcom / VMware Tanzu
Pass: 300 / 500 • 1 Aligned Course
Oracle University
Pass: 68% • 1 Aligned Course
See the exact job positions and realistic salary packages unlocked by Springboot Training, plus which specialized MockAttempt Academy courses to pair next to qualify for higher-paying multi-stack engineering roles.
Spring Boot 3, JPA/Hibernate, Spring Security JWT, MockMvc & live client deployment.
Transaction tuning, Kafka integration, Resilience4j & cloud containerization.
Unlocked by combining Spring Boot with System Design, Kafka, Kubernetes & AWS.
Why Learn Next (For What Purpose): Master Saga choreography, Resilience4j circuit breakers, and high-throughput Kafka event streams.
Why Learn Next (For What Purpose): Package Spring Boot 3 services into hardened Docker images orchestrated on Kubernetes clusters.
Why Learn Next (For What Purpose): Pair your Spring Boot backend with enterprise Angular or React UI dashboards.
MockAttempt Academy keeps enterprise-grade Spring Boot 3 + Data JPA + Security 6 + Testing training accessible at ₹4,499 so every Java aspirant gets 17,500 MCQs, 10 backend capstone projects, and spoken Gemini AI interview verification.
Every single topic includes 10 Timed Mock Tests (each containing 50 Spring Boot MCQs = 500 MCQs per topic) and 10 Spoken Voice + Google Gemini AI Technical Interview rounds.
The AI Interviewer speaks each Spring Boot question aloud via Text-to-Speech, listens to your spoken explanation via microphone Speech-to-Text, normalizes spoken Java/Spring terms, and sends your transcript to the Google Gemini AI verification agent for scoring and follow-up probing.
All MockAttempt Tech Academy fees are 100% fixed and non-negotiable (₹4,499 + 18% GST). We never inflate fake MRPs only to bargain discounts because we refuse to compromise on Senior Industry Expert trainers, small interactive live batches, real cloud/repository labs, daily assessments, or placement mentorship.
MockAttempt Tech Academy ensures you qualify through official exam-blueprint live coaching, timed 50-MCQ scenario simulators, and 1-on-1 readiness audits with unlimited re-tests until you score ≥90%. When you opt to apply for an external proctored exam (AWS, Oracle, Python Institute, MongoDB, PostgreSQL, CNCF, Pearson VUE, etc.), you pay the official exam registration fee to the certification vendor plus a transparent 10% Platform Per-Exam Charge (10% of the fee paid to the vendor + 18% GST) for dedicated exam-readiness verification and booking facilitation. Statutory 18% GST also applies to all course tuition fees with official GST invoices.
How MockAttempt Tech Academy Beats Other Institutes
| Evaluation Criteria | ✨ MockAttempt Tech Academy | ₹2–3L Bootcamps | Recorded Video Sites |
|---|---|---|---|
| Fixed Non-Negotiable Fees | ✓ From $24 USD + 18% GST Skill Tracks & From $536 USD + 18% GST Career Programs • 0% Salary Cut | ✕ Inflated ₹80K–₹2.5L fees + 15%–20% ISA salary cut | △ Flash-sale pricing, zero live mentor support |
| Live Mentorship & Schedule | ✓ 100% Live Senior Architect Sessions (Weekday & Weekend + Day 1–Day N Plan) | △ Crowded 80+ batches or junior TA instructors | ✕ Pre-recorded videos with zero live doubt resolution |
| Topic Mock Tests & Voice AI Viva | ✓ 100% Topic Coverage in Timed MCQ Exams & Spoken Google Gemini AI Interviews | ✕ 1–2 generic tests at the end of training | ✕ Basic 3–5 question quizzes; zero spoken viva |
| Production Repos & Credentials | ✓ Real Module Repos + Live Client Prod Deploy + Barcode Cert & Internship Letter | ✕ Toy clone apps & unverifiable paper certificate | ✕ Copy-along demos; zero internship letter |
| Global Vendor Certifications | 🏅 32+ Official Exams Supported (Vendor Fee by Student + 10% Platform Charge) | ✕ Extra ₹15K–₹30K exam coaching charges | ✕ Self-study videos; zero readiness audit |
| 6-Month Placement Covenant | 🛡️ 100 Verified IT Job Openings in 6 Months via Incentivized Recruiters + Indian MNC & Consultancy Tie-Ups — Or 100% Net Tuition Refund* | ✕ Passive job-board links; zero recruiter closure incentive or refund | ✕ None |
Complete Solution Desk: Enquire for Live IT Courses, 100% Placement-Guaranteed* Career Programs, Unplaced / Career-Gap Placement Support, or Ready-to-Submit College / Final-Year Projects (Code + Report + Viva).
🔒 Fixed & Non-Negotiable Course Fees: Course prices are fixed for every student — zero bargaining so we never compromise on Senior Industry Trainers & placement outcomes.
