annotition范围

最新推荐文章于 2025-09-12 18:08:49 发布

原创最新推荐文章于 2025-09-12 18:08:49 发布 · 129 阅读

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#java

本文详细介绍了Java中的两种枚举类型：ElementType和RetentionPolicy。ElementType枚举定义了源代码元素的种类，如类、字段和方法等；而RetentionPolicy枚举则描述了注解的保留策略，包括源码级、类文件级和运行时级。

1、
public enum ElementType {
/** Class, interface (including annotation type), or enum declaration */
TYPE,

/** Field declaration (includes enum constants) */
FIELD,

/** Method declaration */
METHOD,

/** Parameter declaration */
PARAMETER,

/** Constructor declaration */
CONSTRUCTOR,

/** Local variable declaration */
LOCAL_VARIABLE,

/** Annotation type declaration */
ANNOTATION_TYPE,

/** Package declaration */
PACKAGE
}

2、
public enum RetentionPolicy {
/**
* Annotations are to be discarded by the compiler.
*/
SOURCE,

/**
* Annotations are to be recorded in the class file by the compiler
* but need not be retained by the VM at run time. This is the default
* behavior.
*/
CLASS,

/**
* Annotations are to be recorded in the class file by the compiler and
* retained by the VM at run time, so they may be read reflectively.
*
* @see java.lang.reflect.AnnotatedElement
*/
RUNTIME
}