28.4. ClientExecutionInterceptors

org.jboss.resteasy.spi.interception.ClientExecutionInterceptor classes are client-side only. They run after the MessageBodyWriter, and after the ClientRequest has been built on the client side. They wrap the HTTP invocation that is sent to the server. In RESTEasy GZIP support, they set the Accept header to contain gzip, deflate before the request is sent. In the RESTEasy client cache, they check that the cache contains a resource before attempting to act on a resource. These interceptors must be annotated with both @ClientInterceptor and @Provider.
    public interface ClientExecutionInterceptor
    {
       ClientResponse execute(ClientExecutionContext ctx) throws Exception;
    }

    public interface ClientExecutionContext
    {
       ClientRequest getRequest();

       ClientResponse proceed() throws Exception;
    }

They work similarly to MessageBodyReader in that you must call proceed() or the invocation will be aborted.