Java data object use: PO, DO, TO, DTO, VO, BO, DAO, POJO concept explanation and use

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PO: Persistent Object Persistent Object
The display state of the records in the database table in the java object. The most vivid understanding is that a PO is a record in the database.
A record can be treated as an object, and it can also be easily converted to other objects.
If there is a piece of data in the database, a simple class is now given an instance of this data, then the existing state of this simple class is PO.
(generally/temporarily not used)
DO:Domain Object Domain Object
Used to receive the entity corresponding to the database, it is an abstract data state, between the database and business logic.
Generally, it is used when the Service accesses the database to receive data.
Generally placed under the entity/domain package.
(Common)
TO:Transfer Object Data Transfer Object
An object that is transferred between different relationships in the application.
(generally/temporarily not used)
DTO: Data Tranfer Object Data Transfer Object
This concept comes from the J2EE design pattern, which is a method of transferring data between design patterns software application system. The data transferred by the data is generally the data retrieved by the data access object from the database.
Generally refers to the data transmission object used between the display layer (controller) and the service layer (web front end). It means that the front end submits data to the back end.
(commonly used)
VO: view object value object
The view object is used in the controller layer, and its function is to display a specified page ( Component) encapsulates all the data.
It is generally used in the Service layer to display the view effect control of the web front end. It is the transmission of data from the back end to the front end.
(use less)
BO:business object Business Object
A component that retrieves and processes data. The main function is to encapsulate business logic as an object. This object can contain one or more other objects.
For example, a resume, with educational experience, work experience, social relations, etc. One PO corresponds to one education experience, one PO corresponds to work experience, and one PO corresponds to social relationship. Create a BO object corresponding to the resume to process the resume, and each BO object contains these POs. In this way, when processing these business logics, it can be processed for BO.
(commonly used)
DAO: data access object data access object
is a standard j2ee design pattern of sun.
is a data access interface, which is sandwiched in business logic and database resources.
It is generally used when the Service accesses the database, and can generally operate on sql. Cooperate with VO to provide database CRUD operations.
(When using mybatis, generally not used)

POJO: pain ordinary java object
is a general term for DO/DTO/BO/VO, but it is forbidden to name it as xxx POJO