Data Acces Object

The Data Acces Object (DAO) is a dessing pattern used to acces the information independently. It´s a powerfull tool that help us to make a better clean code and make changges into the dessing. The DAO has 4 parts: entity, the interface DAO, the entity DAO and the service. In the next image we can see a example how is linked

 TestTube class:

This class is the entity of the DAO

DAOInterface class:

This class help us to inherit this general functions into others DAO from the diferents entities.

TestTubeDAO class:

This class contains all functions that can help to acces and handle the information. Also define the methods of the interface

TestTubeService class:

Finally, this class help us to adminitrate the functions on the TestTubeDAO class.

Reference