Understanding the SSM Framework: Integration of Spring MVC, Spring, and MyBatis

Purpose: The SSM framework combines Spring MVC, Spring, and MyBatis into a standard MVC pattern, dividing the system into presentation, controller, service, and DAO layers.

Spring MVC handles request forwarding and view management, while Spring provides business object management and MyBatis serves as the persistence engine for data objects.

Principle – Spring MVC workflow:

1. The client sends a request to DispatcherServlet (the dispatcher).

2. DispatcherServlet consults HandlerMapping to locate the appropriate Controller.

3. The Controller processes the business logic and returns a ModelAndView .

4. DispatcherServlet uses a view resolver to find the view specified by ModelAndView .

5. The view renders the result back to the client.

Spring: The most frequently used component is the IoC container, which loads beans (including classes from service and DAO layers). This eliminates the need for manual new instantiation and enables features such as AOP and transaction management.

MyBatis: MyBatis abstracts JDBC, making low‑level database operations transparent. It operates around a SqlSessionFactory , maps SQL statements to Java methods via mapper XML files, and obtains a SqlSession for each database interaction.

Usage Method:

Define an entity class; its fields usually correspond to database table columns.

Create Mapper.xml (MyBatis) to declare CRUD operations such as insert , selectAll , selectByKey , delete , and update .

Write Mapper.java to map the XML statements to Java methods.

Implement Service.java to provide business services for the controller layer.

Develop Controller.java to handle HTTP requests, map URLs to service methods, and pass data to the view.

Create JSP pages to request parameters and display data.

DataBase → Entity → Mapper.xml → Mapper → Service.java → Controller.java → JSP.

Original source: blog.csdn.net/Dennis_Wu_/article/details/73437097