1. GWT - RPC

2. RPC plumbing diagram

3. package com.mycompany.client; import com.google.gwt.user.client.rpc.RemoteService; public interface MyAddService extends RemoteService { public int add(int a, int b); } RPC plumbing diagram

4. package com.mycompany.server; import com.google.gwt.user.server.rpc.RemoteServiceServlet; import com.mycompany.client.MyAddService; public class MyAddServiceImpl extends RemoteServiceServlet implements MyAddService{ public int add(int a, int b) { int z = a + b; return z; } } RPC plumbing diagram

5. package com.mycompany.client; import com.google.gwt.user.client.rpc.AsyncCallback; public interface MyAddServiceAsync { public void add(int a, int b, AsyncCallback callback); } RPC plumbing diagram

6. Deploy service Tomcat -> add Servlet Hosted mode -> modify module XML

7. Actually making a call button.addClickListener( new ClickListener() { public void onClick(Widget sender) { AddServiceAsync addService = (AddServiceAsync) GWT.create(AddService.class); ServiceDefTarget endpoint = (ServiceDefTarget) addService; String moduleRelativeURL = GWT.getModuleBaseURL() + "myAddService“; endpoint.setServiceEntryPoint(moduleRelativeURL); AsyncCallback callback = new AsyncCallback(){ public void onSuccess(Object result){ resultaatLabel.setText(result.toString()); } public void onFailure(Throwable caught) { resultaatLabel.setText(caught.getMessage()); } }; addService.add(Integer.parseInt(aBox.getText()), Integer.parseInt(bBox.getText()), callback); } } );

8. In Eclipse: GWT Remote Service

10. Cypal studio maakt zelf Async interface en implementatie klasse aan, en past xml file aan Implementatie van methodes moet wel zelf voorzien worden Refresh werkt enkel voor client-side aanpassingen Bij server-side aanpassingen moet heel de applicatie herstart worden

11. Meer info http://code.google.com/docreader/#p=google- web-toolkit-doc-1-5&s=google-web-toolkit-doc- 1-5&t=DevGuideRemoteProcedureCalls