Spring Boot In Action -

./mvnw spring-boot:run → Open http://localhost:8080/api/hello application.properties (or YAML) # Server server.port=9090 server.servlet.context-path=/myapp Logging logging.level.org.springframework=INFO Data source (real DB later) spring.datasource.url=jdbc:mysql://localhost:3306/mydb spring.datasource.username=root spring.datasource.password=secret

management.endpoints.web.exposure.include=health,info,metrics Build a fat JAR: Spring Boot In Action

@SpringBootTest @AutoConfigureMockMvc class BookControllerTest @Autowired private MockMvc mockMvc; public interface BookRepository extends JpaRepository&lt

public interface BookRepository extends JpaRepository<Book, Long> List<Book> findByAuthor(String author); public Book saveBook(Book book) return bookRepo.save(book)

./mvnw package

@Service @RequiredArgsConstructor public class BookService private final BookRepository bookRepo; public Book saveBook(Book book) return bookRepo.save(book);