Spring 1.x modules - bhudevi0924/Spring-boot GitHub Wiki

Spring 1.x modules:

• Core Container: This includes the foundational features like Inversion of Control (IoC) and Dependency Injection (DI). -> Example for DI public class OrderService { private OrderRepository orderRepository;

         // Constructor injection
        public OrderService(OrderRepository orderRepository) {
        this.orderRepository = orderRepository;
       }
  
       public void placeOrder(Order order) {
       orderRepository.save(order);
       }
     }
  

• AOP (Aspect Oriented Programming): Support for Aspect-Oriented Programming to modularize cross-cutting concerns.

      public aspect LoggingAspect {
          before() : execution(* com.example.*.*(..)) {
          System.out.println("Logging method call: " + thisJoinPoint);
          }
       }
  

• Data Access/ Integration: Simplifies integration with various data access technologies like JDBC, Hibernate, etc.

  -> using JDBC: public class JdbcMessageRepository implements MessageRepository { private final JdbcTemplate jdbcTemplate;

          public JdbcMessageRepository(DataSource dataSource) {
          this.jdbcTemplate = new JdbcTemplate(dataSource);
          }
  
          public String getMessage() {
          return jdbcTemplate.queryForObject("SELECT message FROM messages", String.class);
          }
      }
  

• Transaction Management: Provides support for managing transactions in Java applications. (@Transactional)

  @Transactional public void updateMessage(String newMessage) { jdbcTemplate.update("UPDATE messages SET message = ?", newMessage); }

  this method will execute within a transaction, and if any exceptions occur during its execution, the transaction will be rolled back, ensuring data consistency.

• Web: Integration with Servlet API and other web-related technologies.

    @Controller
    public class MessageController {
  
        @Autowired
        private MessageService messageService;
  
        @RequestMapping("/message")
        public String showMessage(Model model) {
        String message = messageService.getMessage();
        model.addAttribute("message", message);
        return "message";
        }
    }
  

• Testing: Support for unit and integration testing of Spring applications.

        @RunWith(SpringJUnit4ClassRunner.class)
        @ContextConfiguration(classes = {TestConfig.class})
        public class MessageServiceTest {
  
            @Autowired
            private MessageService messageService;
  
            @Test
            public void testGetMessage() {
            String message = messageService.getMessage();
            assertEquals("Expected message", message);
            }
        }