如何使用idea看注解的实现

需求

想看看注解 @AliasFor 是如何实现的

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    /**
        * Create an {@code AliasDescriptor} <em>from</em> the declaration
        * of {@code @AliasFor} on the supplied annotation attribute and
        * validate the configuration of {@code @AliasFor}.
        * @param attribute the annotation attribute that is annotated with
        * {@code @AliasFor}
        * @return an alias descriptor, or {@code null} if the attribute
        * is not annotated with {@code @AliasFor}
        * @see #validateAgainst
        */
    @Nullable
    public static AliasDescriptor from(Method attribute) {
        AliasDescriptor descriptor = aliasDescriptorCache.get(attribute);
        if (descriptor != null) {
            return descriptor;
        }

        AliasFor aliasFor = attribute.getAnnotation(AliasFor.class);
        if (aliasFor == null) {
            return null;
        }

        descriptor = new AliasDescriptor(attribute, aliasFor);
        descriptor.validate();
        aliasDescriptorCache.put(attribute, descriptor);
        return descriptor;
    }