The Java background framework is mainly composed of five major layers: DAO layer, ENTITY layer, SERVICE layer, CONTROLLER layer and View layer.
The analysis is as follows:
1. DAO layer: Persistence layer mainly interacts with the database
The DAO layer mainly does the work of the data persistence layer and mainly interacts with the database. The DAO layer will first create the DAO interface, and then define the implementation class of the interface in the configuration file. Then you can call the DAO interface in the module to process the data business, and you don't need to pay attention to which specific implementation class of this interface is.
The data source and database connection parameters of the DAO layer are configured in the configuration file.
Recommended learning:java video tutorial
2. Entity layer (domain layer) Entity layer
The database class in the project.
3. Service layer (biz): Business layer Control business
The Service layer is mainly responsible for the logical application design of the business module. Like the DAO layer, the interface is designed first, then the class to be implemented is created, and then the association of its implementation is configured in the configuration file. Next, you can call the interface in the service layer to process the business logic application.
Encapsulating the business logic of the Service layer is conducive to the independence and reusability of the business logic.
4. Controller layer: (action layer) Control layer
Control business logic.
The Controller layer is responsible for the control of specific business module processes. The controller layer mainly calls the interface in the Service layer to control specific business processes. The control configuration also needs to be carried out in the configuration file.
5. View layer
This layer is closely integrated with the control layer, and they need to be combined to work together. The View layer is mainly responsible for the presentation of the front-end jsp page.
The difference between the Controller layer and the Service layer is: the Controller layer is responsible for the control of specific business module processes; the Service layer is responsible for the logical application design of the business module;
Summary: In a specific project, The process is: the Controller layer calls the method of the Service layer, and the Service layer calls the method of the Dao layer, in which the parameters of the call are passed using the Entity layer.
Recommended related articles and tutorials:java introductory tutorial
The above is the detailed content of The java background framework mainly consists of several layers. For more information, please follow other related articles on the PHP Chinese website!