Java Annotations - looking for an example of RetentionPolicy.CLASS

Question

Hi,

according to Java Annotation API:

• 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.

• 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.

I am looking for a sample of "CLASS" retention policy. when we need to use this policy instead of RUNTIME policy.

Thanks in advance.

Answer 1

Of all of the large number of libraries I have in my current project. the only examples I can find are in the Google Guava library, for example com.google.common.annotations.GwtCompatible.

I'm not really sure why they chose this retention policy, though - perhaps for tools support, where the tools read the class files themselves, rather than going through the reflection API. I'm not sure that I really see the point of this distinction, though.