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Java注释是否可序列化？

[英]Are Java annotations serializable?

原文 2013-04-09 14:32:47 6 2 java/ serialization/ annotations

The Java Annotation interface does not extend Serializable . Java Annotation接口不扩展Serializable 。 However, Java annotation values are serializable (implemented using java.lang.reflect.Proxy , with a serializable invocation handler). 但是，Java注释值是可序列化的（使用java.lang.reflect.Proxy实现，带有可序列化的调用处理程序）。

Is this guaranteed anywhere? 这有保证吗？ My search-foo is failing to find a reference. 我的search-foo未能找到参考。 Or if I need to serialize annotation instances safely, do I need to create my own serialization proxies? 或者如果我需要安全地序列化注释实例，我是否需要创建自己的序列化代理？

2 个解决方案

Annotation objects returned by methods of java.lang.reflect.AnnotatedElement are Serializable . java.lang.reflect.AnnotatedElement方法返回的注释对象是Serializable 。 This is what API says : This interface allows annotations to be read reflectively. 这就是API所说的： 此接口允许以反射方式读取注释。 All annotations returned by methods in this interface are immutable and serializable . 此接口中的方法返回的所有注释都是不可变的和可序列化的 。

All classes capable of returning annotation objects (Class, Constructor, Field, Method, Package, Parameter) implement AnnotatedElement and are obliged to create / return Serializable objects by the above contract. 所有能够返回注释对象的类（类，构造函数，字段，方法，包，参数）都实现了AnnotatedElement，并且必须通过上述契约创建/返回Serializable对象。

Annotations are part of the class definition, and thus would never be written to a serialization stream (at least not with standard java serialization) when serializing an instance of a class which has annotations. 注释是类定义的一部分，因此在序列化具有注释的类的实例时，永远不会将其写入序列化流（至少不使用标准java序列化）。

UPDATE: I guess i missed the point of the original question which was referring to specifically serializing an instance of an actual Annotation. 更新：我想我错过了原始问题的意思，它指的是专门序列化实际注释的实例。