@Target(value=TYPE)
 @Retention(value=RUNTIME)
 @Documented
public @interface ConstrainedTo

Indicates the run-time context in which an annotated provider is applicable. If a @ConstrainedTo annotation is not present on a provider type declaration, the declared provider may be used in any run-time context. If such a annotation is present, the runtime will enforce the specified usage restriction.

The following example illustrates restricting a MessageBodyReader provider implementation to run only as part of a Client run-time:

  @ConstrainedTo(RuntimeType.CLIENT)
  public class MyReader implements MessageBodyReader {
      ...
  }
 

The following example illustrates restricting a WriterInterceptor provider implementation to run only as part of a Server run-time:

  @ConstrainedTo(RuntimeType.SERVER)
  public class MyWriterInterceptor implements WriterInterceptor {
      ...
  }
 

It is a configuration error to constraint a provider implementation to a run-time context in which the provider cannot be applied. In such case, the runtime SHOULD inform a user about the issue and ignore the provider implementation in further processing.

For example, the following restriction of a ClientRequestFilter to run only as part of the server run-time would be considered invalid:

  // reported as invalid and ignored by the runtime
  @ConstrainedTo(RuntimeType.SERVER)
  public class MyFilter implements ClientRequestFilter {
      ...
  }