<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE module PUBLIC "-//Google Inc.//DTD Google Web Toolkit 1.6.4//EN" "http://google-web-toolkit.googlecode.com/svn/tags/1.6.4/distro-source/core/src/gwt-module.dtd">
<module rename-to='de_vogella_gwt_helloworld'>
  <!-- Inherit the core Web Toolkit stuff.                        -->
  <inherits name='com.google.gwt.user.User'/>

  <inherits name='com.google.gwt.user.theme.standard.Standard'/>

  <!-- Specify the app entry point class.                         -->
  <entry-point class='de.vogella.gwt.helloworld.client.HelloGwt'/>
</module>

package de.vogella.gwt.helloserver.client.model;

import java.io.Serializable;

public class MyUser implements Serializable {
    private static final long serialVersionUID = 1L;

    private String id;
    private String username;
    private String numberOfHits;

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    /**
     * @return the numberOfHits
     */
    public String getNumberOfHits() {
        return numberOfHits;
    }

    /**
     * @param numberOfHits
     *            the numberOfHits to set
     */
    public void setNumberOfHits(String numberOfHits) {
        this.numberOfHits = numberOfHits;
    }

    //  
}

package de.vogella.gwt.helloserver.client.service;

import java.util.List;

import com.google.gwt.user.client.rpc.RemoteService;
import com.google.gwt.user.client.rpc.RemoteServiceRelativePath;

import de.vogella.gwt.helloserver.client.model.MyUser;

// 
@RemoteServiceRelativePath("userService")
public interface MyUserService extends RemoteService {
    List<MyUser> getUserList();
    MyUser getUser(String id);
}

package de.vogella.gwt.helloserver.client.service;

import java.util.List;

import com.google.gwt.user.client.rpc.AsyncCallback;

import de.vogella.gwt.helloserver.client.model.MyUser;

public interface MyUserServiceAsync {
    void getUserList(AsyncCallback<List<MyUser>> callback);
    void getUser(String id, AsyncCallback<MyUser> callback);
}

package de.vogella.gwt.helloserver.server;

import java.util.ArrayList;
import java.util.List;

import com.google.gwt.user.server.rpc.RemoteServiceServlet;

import de.vogella.gwt.helloserver.client.model.MyUser;
import de.vogella.gwt.helloserver.client.service.MyUserService;

public class MyUserServiceImpl extends RemoteServiceServlet implements
        MyUserService {

    private static final long serialVersionUID = 1L;

    private List<MyUser> userList = new ArrayList<MyUser>();

    public MyUserServiceImpl() {
        MyUser user = new MyUser();
        user.setId("1");
        user.setUsername("Peter");
        user.setNumberOfHits("15");
        userList.add(user);

        user = new MyUser();
        user.setId("2");
        user.setUsername("Hanz");
        user.setNumberOfHits("25");
        userList.add(user);
    }

    public MyUser getUser(String id) {

        for (Object object : userList) {
            if (((MyUser) object).getId().equals(id))
                return ((MyUser) object);
        }
        return null;
    }

    public List<MyUser> getUserList() {
        return userList;
    }
}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE web-app
    PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
    "http://java.sun.com/dtd/web-app_2_3.dtd">

<web-app>

  <!-- Default page to serve -->
  <welcome-file-list>
    <welcome-file>De_vogella_gwt_helloserver.html</welcome-file>
  </welcome-file-list>
  
  <!-- Servlets -->
  <servlet>
    <servlet-name>userServlet</servlet-name>
    <servlet-class>de.vogella.gwt.helloserver.server.MyUserServiceImpl</servlet-class>
  </servlet>
  
  <servlet-mapping>
    <servlet-name>userServlet</servlet-name>
    <url-pattern>/de_vogella_gwt_helloserver/userService</url-pattern>
  </servlet-mapping>

</web-app>

package de.vogella.gwt.helloserver.client.table;

import java.util.ArrayList;
import java.util.List;

import de.vogella.gwt.helloserver.client.model.MyUser;

public class DataSource {

    private final List<MyUser> users;
    private List<String> header;

    public DataSource(List<MyUser> users) {
        header = new ArrayList<String>();
        header.add("Id");
        header.add("Name");
        header.add("Number of Hits");
        this.users = users;
    }

    public List<MyUser> getUsers() {
        return users;
    }

    public List<String> getTableHeader() {
        return header;
    }

}

package de.vogella.gwt.helloserver.client.table;

import java.util.List;

import com.google.gwt.user.client.ui.FlexTable;

import de.vogella.gwt.helloserver.client.model.MyUser;

public class MyTable extends FlexTable {
    DataSource input;

    public MyTable(DataSource input) {
        super();
        this.setCellPadding(1);
        this.setCellSpacing(0);
        this.setWidth("100%");
        this.setInput(input);
    }

    public void setInput(DataSource input) {
        for (int i = this.getRowCount(); i > 0; i--) {
            this.removeRow(0);
        }
        if (input == null) {
            return;
        }

        int row = 0;
        List<String> headers = input.getTableHeader();
        if (headers != null) {
            int i = 0;
            for (String string : headers) {
                this.setText(row, i, string);
                i++;
            }
            row++;
        }
        // make the table header look nicer
        this.getRowFormatter().addStyleName(0, "tableHeader");

        List<MyUser> rows = input.getUsers();
        int i = 1;
        for (MyUser myUser : rows) {
            this.setText(i, 0, myUser.getId());
            this.setText(i, 1, myUser.getUsername());
            this.setText(i, 2, myUser.getNumberOfHits());
            i++;
        }
        this.input = input;
    }
}

package de.vogella.gwt.helloserver.client.service;

import java.util.List;

import com.google.gwt.user.client.Window;
import com.google.gwt.user.client.rpc.AsyncCallback;

import de.vogella.gwt.helloserver.client.model.MyUser;
import de.vogella.gwt.helloserver.client.table.DataSource;
import de.vogella.gwt.helloserver.client.table.MyTable;

/**
 * Class which handles the asynchronous callback from the server
 * <p>
 * Need to react on server communication failure and success
 * 
 * @author Lars Vogel
 * 
 */
public class MyUserCallback implements AsyncCallback<List<MyUser>> {

    private MyTable table;

    public MyUserCallback(MyTable table) {
        this.table = table;
    }

    public void onFailure(Throwable caught) {
        Window.alert(caught.getMessage());
    }

    public void onSuccess(List<MyUser> result) {
        List<MyUser> users = result;
        DataSource datasource = new DataSource(users);
        table.setInput(datasource);
        for (MyUser user : users) {
            System.out.println(user.getUsername());
        }
    }

}

package de.vogella.gwt.helloserver.client.entrypoint;

import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.core.client.GWT;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.user.client.rpc.ServiceDefTarget;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.DialogBox;
import com.google.gwt.user.client.ui.RootPanel;
import com.google.gwt.user.client.ui.VerticalPanel;

import de.vogella.gwt.helloserver.client.service.MyUserCallback;
import de.vogella.gwt.helloserver.client.service.MyUserService;
import de.vogella.gwt.helloserver.client.service.MyUserServiceAsync;
import de.vogella.gwt.helloserver.client.table.MyTable;

/**
 * Entry point classes define <code>onModuleLoad()</code>.
 */
public class HelloServer implements EntryPoint {

    private MyTable table;

    /**
     * This is the entry point method.
     */
    public void onModuleLoad() {
        table = new MyTable(null);

        Button button = new Button("Click me");

        // We can add style names
        button.addStyleName("pc-template-btn");
        // or we can set an id on a specific element for styling

        VerticalPanel vPanel = new VerticalPanel();
        vPanel.setWidth("100%");
        vPanel.setHorizontalAlignment(VerticalPanel.ALIGN_CENTER);
        vPanel.add(button);

        vPanel.add(table);

        // add table and button to the RootPanel
        RootPanel.get().add(vPanel);

        // create the dialog box
        final DialogBox dialogBox = new DialogBox();
        dialogBox.setText("Welcome to GWT Server Communication!");
        dialogBox.setAnimationEnabled(true);
        Button closeButton = new Button("close");
        VerticalPanel dialogVPanel = new VerticalPanel();
        dialogVPanel.setWidth("100%");
        dialogVPanel.setHorizontalAlignment(VerticalPanel.ALIGN_CENTER);
        dialogVPanel.add(closeButton);

        closeButton.addClickHandler(new ClickHandler() {
            @Override
            public void onClick(ClickEvent event) {
                dialogBox.hide();
            }
        });

        // Set the contents of the Widget
        dialogBox.setWidget(dialogVPanel);

        button.addClickHandler(new ClickHandler() {
            @Override
            public void onClick(ClickEvent event) {
                MyUserServiceAsync service = (MyUserServiceAsync) GWT
                        .create(MyUserService.class);
                ServiceDefTarget serviceDef = (ServiceDefTarget) service;
                serviceDef.setServiceEntryPoint(GWT.getModuleBaseURL()
                        + "userService");
                MyUserCallback myUserCallback = new MyUserCallback(table);
                service.getUserList(myUserCallback);
            }
        });

    }
}

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE module PUBLIC "-//Google Inc.//DTD Google Web Toolkit 1.6.4//EN" "http://google-web-toolkit.googlecode.com/svn/tags/1.6.4/distro-source/core/src/gwt-module.dtd">

<module rename-to='de_vogella_gwt_helloserver'>
  <inherits name='com.google.gwt.user.User'/>
  <inherits name='com.google.gwt.user.theme.standard.Standard'/>

  <!-- Specify the app entry point class.                         -->
  <entry-point class='de.vogella.gwt.helloserver.client.entrypoint.HelloServer'/>

</module>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>
  <head>
    <meta http-equiv="content-type" content="text/html; charset=UTF-8">
    <link type="text/css" rel="stylesheet" href="De_vogella_gwt_helloserver.css">
    <title>Web Application Starter Project</title>
    
    <script type="text/javascript" language="javascript" src="de_vogella_gwt_helloserver/de_vogella_gwt_helloserver.nocache.js"></script>
  </head>

  <body>
</body>
</html>

body {
  padding: 10px;
}

/* stock list header row */
.tableHeader {
  background-color: #2062B8;
  color: white;
  font-style: italic;
}

package de.vogella.gwt.module.model;

public class Person {
    private String firstName;

    /**
     * @return the firstName
     */
    public String getFirstName() {
        return firstName;
    }

    /**
     * @param firstName
     *            the firstName to set
     */
    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

}

<module>
  <inherits name='com.google.gwt.user.User'/>
  <source path="model"></source>
</module>

package de.vogella.gwt.module.application.client;

import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.RootPanel;

import de.vogella.gwt.module.model.Person;

public class ModulTest implements EntryPoint {

    @Override
    public void onModuleLoad() {
        Person p = new Person();
        p.setFirstName("Lars");
        Label label = new Label("Hello " + p.getFirstName());
        RootPanel.get().add(label);
    }
}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE module PUBLIC "-//Google Inc.//DTD Google Web Toolkit 1.6.4//EN" "http://google-web-toolkit.googlecode.com/svn/tags/1.6.4/distro-source/core/src/gwt-module.dtd">
<module rename-to='de_vogella_gwt_module_application'>
  <!-- Inherit the core Web Toolkit stuff.                        -->
  <inherits name='com.google.gwt.user.User'/>

  <inherits name='com.google.gwt.user.theme.standard.Standard'/>
  <inherits name='de.vogella.gwt.module.model'/>

  <!-- Other module inherits                                      -->

  <!-- Specify the app entry point class.                         -->
  <entry-point class='de.vogella.gwt.module.application.client.ModulTest'/>
</module>