动态地向现有类添加注释 [英] Dynamically add annotation to an existing class

问题描述

我有以下课程

public class Person {
   ...
}

我想创建另一个看起来像这样的类。

I would like to create another class that would look like this.

@SomeAnnotation
public class Person {
   ...
}

通过类似的简单方法。

public static Class addAnnotation(Class originalType, Class<? extends Annotation> annotation) {
   // what goes here?
}

例如，通过ASM有一种简单的方法吗？我需要什么依赖项。我试过谷歌这个但是我发现的例子要么不完整要么正在做其他事情。其他框架如javassist也同样好。

Is there an easy way to do this via ASM for example? What dependencies would I need. I have tried to Google this however the examples I have found are either incomplete or are doing something else. Other frameworks such as javassist would be just as good.

推荐答案

你可以使用 javassist 项目。

使用javassist它将看起来像这样：

With javassist it will be look something like that:

ClassFile cf = ... ;
ConstPool cp = cf.getConstPool();
AnnotationsAttribute attr = new AnnotationsAttribute(cp, AnnotationsAttribute.visibleTag);

Annotation a = new Annotation("Author", cp);
a.addMemberValue("name", new StringMemberValue("Chiba", cp));
attr.setAnnotation(a);
cf.addAttribute(attr);
cf.setVersionToJava5();

希望有所帮助。
Alexey

Hope it helps. Alexey

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