The technical principles of Apache Yetus Audience Annotations in the Java class library class libraries)

Apache Yetus Audience Annotions is a framework for the technical principles for Java libraries. It allows developers to use annotations to define code on class, methods, and fields to define code.The goal of this framework is to accurately describe the expected use and restrictions of the code by providing a wealth of annotations, thereby improving the maintenance and readability of the code. Apache Yetus Audience Annotations Framework includes the following key concepts: 1. Note: The framework provides a set of annotations for the audience information in the code.These annotations include @Public,@limitedprivate and @private.@Public Note states that the code is open and accessible to all users.@Limitedprivate Note indicates that the code has restricted access to the specified group of users. 2. Use scenario: Developers can choose appropriate annotations to mark the code according to the use scenario of the code.For example, a developer can use @Public annotations on the public API interface to use the interface to use the interface; and use @Private annotations in private methods to restrict the access only internal code can be accessed. 3. Analysis device: In order to correctly analyze the annotation, the framework provides a commentary parser.The parser can extract the annotations in the source code and generate related metadata in order to be used in subsequent code analysis and inspection.The parser can use the Java reflection mechanism to read and analyze the annotation. The following is a simple example code that demonstrates how to use Apache Yetus Audience Annotations in the Java class library: import org.apache.yetus.audience.InterfaceAudience; import org.apache.yetus.audience.InterfaceStability; @InterfaceAudience.Public @InterfaceStability.Evolving public class ExampleClass { @InterfaceAudience.Public public void publicMethod() { // The realization of public methods } @InterfaceAudience.LimitedPrivate({"user1", "user2"}) public void limitedMethod() { // With the implementation of restrictions on access methods } @InterfaceAudience.Private public void privateMethod() { // Realization of private methods } } In the above sample code, the ExampleClass class uses the annotations in the Apache Yetus Audience Annitations framework to mark the audience.PublicMethod () method is marked as @Public, indicating that it is open and accessible; the LimitedMethod () method is marked as @limitedPrivate, and the user "User1" and "User2" can be accessed; PrivateMethod alone;() The method is marked as @private, indicating that it is private, and only internal code can be accessed. By using Apache Yetus Audience Annotations framework, developers can clearly specify the audience of the code in the code to improve the readability and maintenance of the code.This framework can help the team better manage the code and ensure that it uses and maintain it correctly.