如何将多个注释合并为一个? [英] How to combine multiple annotations to single one?

问题描述

我有两个来自一个框架的注释.我经常在同一个字段上使用这两个注释.因此，我试图创建一个包含这两个的组合"注释.

I have two annotations from a framework. Often I use those two annotations both on the same field. Thus I'm trying to create a "combined" annotation that contains that both two.

但我不知道这是否可能:

But I don't know if it is possible at all:

现有注释(我无法控制):

@Target({ElementType.PARAMETER, ElementType.METHOD, ElementType.FIELD})
@Retention(RetentionPolicy.RUNTIME)
public @interface ApiParam {
    String name() default "";
}

@Target({ElementType.METHOD, ElementType.FIELD})
@Retention(RetentionPolicy.RUNTIME)
public @interface ApiModelProperty {
    String name() default "";
}

我正在尝试创建的自定义注释:

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.ANNOTATION_TYPE)
@ApiParam
@ApiModelProperty
public @interface SwaggerParam {
     String name() default "";
}

结果:注释不适用于注释类型.

问题:有机会吗?

推荐答案

很遗憾，您无法执行此操作，因为无法扩展注释.

Unfortunately you can't do this since it is not possible to extend annotations.

Java 中有没有类似注解继承的东西?

当我第一次回答这个问题时，我最初对 Spring 框架解决这个缺点的方法感到困惑，他们使用元级注释(例如 @Component 作为 @Controller/@Configuration 等的元注释)作为一种解决方法.

When I first answered this I was initially confused by the Spring framework approach to this shortcoming whereby they use meta level annotations (such as @Component as a meta annotation for @Controller/@Configuration etc.) as a sort of workaround.

参见:https://docs.spring.io/spring/docs/3.2.x/spring-framework-reference/html/beans.html#beans-annotation-config

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