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Editor to share with you what Hibernate refers to. I hope you will get something after reading this article. Let's discuss it together.

What is Hibernate? Explain from different angles:

1. It is the middleware that connects Java applications and relational databases.

2. It encapsulates JDBC API and is responsible for the persistence of Java objects.

3. In the hierarchical software architecture, it is located in the persistence layer, which encapsulates all the data access details, so that the business grass-roots level can focus on the implementation of business logic.

4. It is an ORM (Object-Relation Mapping object-relational mapping) tool, which can establish the mapping of object-oriented domain model and relational model.

Application hierarchical architecture:

1. Presentation layer: provides an interface to interact with users.

2. Business logic layer: realize all kinds of business logic.

3. Data layer: the persistence business responsible for storing and managing applications.

Software layering has two meanings:

One type of ◆ is physical layering, in which each layer runs on a separate machine, which means creating distributed software systems.

One type of ◆ is logical layering, which refers to the completion of specific functions in a single software module.

Software layering must meet the following characteristics:

1. Each layer consists of a set of related classes or components that work together to accomplish specific functions.

2. There is a top-down dependency between layers, that is, the upper components will access the API of the lower components, while the lower components should not rely on the upper components.

3. Each layer exposes API to the upper layer, but the implementation details are transparent to the outside world.

Advantages of software layering:

Proper layering will improve the following performance of the software.

1. Scalability: whether the application supports more users. For example, a database connection.

2. Maintainability: when requirements change, only one part of the software needs to be modified and other parts of the code will not be affected.

3. Scalability: how easy it is to add new functions to existing systems.

4. Reusability: there is no redundancy in the program code, and the same program can meet multiple requirements.

5. Manageability: the degree of difficulty of the management system.

Disadvantages:

1. The more layers there are, the higher the requirements for software designers are.

2. The more layers, the more difficult it is to debug.

The table ensures the * * nature of each record through the master, and the primary key of the table should not have any business meaning, because any column that has business meaning has the possibility of change. One of the most important theories of relational database science is: don't give any business meaning to keywords.

In the domain model, there are four relationships between classes:

1. Association: the application relationship between classes. If class An is associated with class B, then the referenced class B will be defined as an attribute of class A. Associations can also be divided into single associations and two-way associations.

2. Dependency: the access relationship between classes. If class An accesses the properties or methods of class B, or if class An is responsible for instantiating class B, then class A depends on class B.

3. Aggregation: the relationship between the whole and the part.

4. Inheritance

After reading this article, I believe you have a certain understanding of "what Hibernate means". If you want to know more about it, you are welcome to follow the industry information channel. Thank you for your reading!

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