{"id": 2, "result": {"Planet": {"Earth": 1, "Mars": 2,....

Map<String, Map<String, Integer>>

{"id": 1, "result": ["Planet", "Stars"], "error": null}

import com.google.gwtjsonrpc.common.AsyncCallback;
import com.google.gwtjsonrpc.common.RemoteJsonService;
import com.google.gwtjsonrpc.common.RpcImpl;

@RpcImpl(version=RpcImpl.Version.V2_0,transport=RpcImpl.Transport.HTTP_POST)
public interface ControlService extends RemoteJsonService
{
    RegisterValues RegisterValues = new RegisterValues(); //Used in the Second Example

    public void connectedCNames( String [] Names, AsyncCallback<String[]> callback ); //FirstExample

    public void myRegisterValues( String [] Names, AsyncCallback<Map<String,RegisterValues>> callback); //Second Example
    //public void myRegisterValues( String [] Names, AsyncCallback<Map<String,Map<String, Integer>> callback); //version that doesn't work but should

}

import com.google.gwtjsonrpc.common.AsyncCallback;

public class createPanel implements ChangeHandler{

    public mainPanel{

        //Some code setting up the panels
        service_ = GWT.create(ControlService.class);
        ((ServiceDefTarget) service_).setServiceEntryPoint("http://localhost:3900/services/ControlProxy.py");

        service_.connectedNames( new String[0], new AsyncCallback<String[]>() {

            public void onSuccess( String[] result)
            {
                    //This works, it returns back a parsed JSON Object in the form of an array of strings as expected
            }
            public void onFailure(Throwable why)
            {
                myList_.addItem( "Server error!" );
            }
    });
    }
}

{"id": 2, "result": {"Planet": {"Earth": 1, "Mars": 2,....

public void myRegisterValues( String [] Names, AsyncCallback<Map<String,Map<String, Integer>> callback);

service_.myRegisterValues( names, new AsyncCallback<Map<String,Map<String, Integer>>();

public void RegisterValues( String [] Names, AsyncCallback<Map<String,RegisterValues>> callback);

public class RegisterValues
    {
        int Earth;
        int Mars;
            //etc.

02:18:48.395 [ERROR] Errors in 'generated://AF9BA58B045D92E7896CD657C9CC5FAF/example/client/GlibControlService_JsonProxy.java'
    02:18:48.395 [ERROR] Line 18: INSTANCE cannot be resolved or is not a field

02:18:48.398 [ERROR] Failed to create an instance of 'example.client.ControlService' via deferred binding