Java Custom Annotations

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When there is only one member, the member name must be taken as value (). You can assign a value directly when you use it!

Use the following:

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Note Classes can have no members, called identity annotations.

Use the following:

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Annotations cannot be used for annotations of classes if the annotation scope has only methods and no classes:

Error in class use!

If the annotation scope has only classes, then annotations cannot be used for methods!

@Target defines a scope, preceded by a method, followed by a class.

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Life cycle:

If the lifetime of the annotation is set to source, the runtime annotations will not exist, and the console will not have the parse result unless the source code is present:

If you change to class:

Must be an explanation of what the runtime is able to extract:

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Inheritance of annotations:

Because it is an interface, inheritance does not work and the console has no output. The way to inherit from an interface does not work, and then it changes to a class to see: Changing the Person class to the Class,child class inherits the person class.

Console output:

Summary: Annotations inherit only the annotations above the class and do not inherit annotations on the method.

Java Custom Annotations