Spring Boot – 100+ Lab Exercises (Basic, Intermediate, Advanced)

🔰 Basic Level (30+ Exercises)

Goal: Learn the fundamentals of Spring Boot development and RESTful API creation.

Getting Started with Spring Boot

• Setup Spring Boot project using Spring Initializr

• Create a simple RESTful “Hello World” API

• Understand Spring Boot application structure

• Run Spring Boot app using embedded Tomcat

• Build and run Spring Boot jar

Spring Boot Fundamentals

• Create Controller and handle HTTP GET requests

• Handle POST requests with @RequestBody

• Path variables and query parameters

• Exception handling with @ControllerAdvice

• Custom error response structure

Dependency Injection & Beans

• Create and inject Beans using @Component and @Autowired

• Bean lifecycle with @PostConstruct and @PreDestroy

• Configuration properties with @Value

• Use @Configuration and @Bean annotations

• Profiles and environment-specific properties

Data Access with Spring Data JPA

• Setup H2 in-memory database

• Define Entity classes

• Create Repository interfaces

• Basic CRUD operations

• Custom queries with @Query

🚀 Intermediate Level (40+ Exercises)

Goal: Master real-world REST APIs, Spring Security, and business logic architecture.

REST API Advanced Concepts

• Pagination and Sorting with Pageable

• Filtering data via query params

• Implement PATCH requests

• Use DTOs with ModelMapper

• Implement validation with @Valid and @NotNull

Security with Spring Security

• Basic authentication setup

• Role-based authorization

• JWT token generation and validation

• Securing REST APIs

• Password encoding with BCrypt

Service Layer and Business Logic

• Create Service classes with @Service

• Transaction management with @Transactional

• Asynchronous services with @Async

• Implement caching with Spring Cache

• Use AOP for logging

Database and Persistence

• Migrate from H2 to MySQL/PostgreSQL

• Relationships (@OneToMany, @ManyToOne)

• Cascade types and Fetch types

• Auditing with @CreatedDate and @LastModifiedDate

• Database migrations with Flyway

File Upload & Download

• Upload files with Multipart

• Serve files via REST API

• Store files in DB vs filesystem

• Implement file size limits

• Validate file types

🧠 Advanced Level (30+ Exercises)

Goal: Engineer scalable microservices and deploy them to cloud infrastructure.

Microservices Architecture

• Create multiple Spring Boot microservices

• Service registration with Eureka

• Client-side load balancing with Ribbon

• API Gateway with Spring Cloud Gateway

• Distributed tracing with Sleuth and Zipkin

Messaging & Integration

• Async communication with RabbitMQ

• Kafka integration

• REST API integration using WebClient

• Scheduled tasks with @Scheduled

• Event-driven programming with ApplicationEvents

Monitoring & Health Checks

• Actuator endpoints setup

• Custom health indicators

• Metrics and Prometheus integration

• Log aggregation with ELK stack

• Centralized configuration with Spring Cloud Config

Testing & CI/CD

• Unit testing with JUnit 5

• Mocking with Mockito

• Integration testing with @SpringBootTest

• Testcontainers for DB testing

• Setup CI/CD pipeline for Spring Boot app

Cloud Deployment & Scaling

• Dockerize Spring Boot app

• Deploy to Kubernetes cluster

• Auto-scaling with Kubernetes HPA

• Deploy on AWS Elastic Beanstalk

• Use AWS RDS for DB

🚀 Capstone Projects & Use Cases

• Build E-Commerce REST API with user roles and payment simulation

• Employee Management System with audit logs

• Social Media Feed microservice architecture

• Real-time chat service with WebSocket

• IoT data ingestion backend

✅ Tools & Ecosystem

• IDE: IntelliJ IDEA / Eclipse

• Build Tools: Maven / Gradle

• Database: H2, MySQL, PostgreSQL

• Cloud: AWS / Azure / GCP (optional)

• DevOps: Docker, Kubernetes, Jenkins, GitHub Actions