程序包 java.lang.annotation

枚举 RetentionPolicy

java.lang.Object

java.lang.Enum<RetentionPolicy>

java.lang.annotation.RetentionPolicy

所有已实现的接口:

Serializable, Comparable<RetentionPolicy>

public enum RetentionPolicy
extends Enum<RetentionPolicy>

Annotation retention policy. The constants of this enumerated type describe the various policies for retaining annotations. They are used in conjunction with the Retention meta-annotation type to specify how long annotations are to be retained.

从以下版本开始:

1.5

枚举常量概要

枚举常量

枚举常量	说明
CLASS	Annotations are to be recorded in the class file by the compiler but need not be retained by the VM at run time.
RUNTIME	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.
SOURCE	Annotations are to be discarded by the compiler.

方法概要

限定符和类型	方法	说明
static RetentionPolicy	valueOf(String name)	返回带有指定名称的该类型的枚举常量。 字符串必须与用于声明该类型的枚举常量的 标识符完全匹配。(不允许有多余 的空格字符。)
static RetentionPolicy[]	values()	按照声明该枚举类型的常量的顺序, 返回 包含这些常量的数组。该方法可用于迭代 常量, 如下所示: for (RetentionPolicy c : RetentionPolicy.values()) System.out.println(c);

从类继承的方法 java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

从类继承的方法 java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

枚举常量详细资料

SOURCE

public static final RetentionPolicy SOURCE

Annotations are to be discarded by the compiler.

CLASS

public static final RetentionPolicy CLASS

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.

RUNTIME

public static final RetentionPolicy RUNTIME

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.

另请参阅:

AnnotatedElement

方法详细资料

values

public static RetentionPolicy[] values()

按照声明该枚举类型的常量的顺序, 返回 包含这些常量的数组。该方法可用于迭代 常量, 如下所示:

for (RetentionPolicy c : RetentionPolicy.values())
    System.out.println(c);

返回:

按照声明该枚举类型的常量的顺序返回的包含这些常量的数组

valueOf

public static RetentionPolicy valueOf(String name)

返回带有指定名称的该类型的枚举常量。 字符串必须与用于声明该类型的枚举常量的 标识符完全匹配。(不允许有多余 的空格字符。)

参数:

name - 要返回的枚举常量的名称。

返回:

返回带有指定名称的枚举常量

抛出:

IllegalArgumentException - 如果该枚举类型没有带有指定名称的常量

NullPointerException - 如果参数为空值