你不用改动任何文件，立即运行，看看你的第一个google app:
你一定猜到了，google appengine eclipse plugin给你生成的是一个gwt ajax应用，呵呵，你立即进入到web2.0时代了。
很简单，很easy，google appengine for java很令人心动。。。
简单小结一下：
1. appengine for java开发包相当友好
2. appengine for java对ide也相当友好
3. appengine for java的webapp就是一个war
4. appengine for java开发包使用了geronimo
5. appengine for java使用了jdo作为数据接口
6. appengine for java支持gwt
8. appengine for java可以写jsp和servlet
9. appengine for java开发包使用了jetty和javadb?
...
来看看一段代码吧，一切尽在代码中
Java代码
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ page import="java.util.List" %>
<%@ page import="javax.jdo.PersistenceManager" %>
<%@ page import="com.google.appengine.api.users.User" %>
<%@ page import="com.google.appengine.api.users.UserService" %>
<%@ page import="com.google.appengine.api.users.UserServiceFactory" %>
<%@ page import="guestbook.Greeting" %>
<%@ page import="guestbook.PMF" %>
<html>
<head>
<link type="text/css" rel="stylesheet" href="/stylesheets/main.css" />
</head>
<body>
<%
UserService userService = UserServiceFactory.getUserService();
User user = userService.getCurrentUser();
if (user != null) {
%>
<p>Hello, <%= user.getNickname() %>! (You can
<a href="<%= userService.createLogoutURL(request.getRequestURI()) %>">sign out</a>.)</p>
<%
} else {
%>
<p>Hello!
<a href="<%= userService.createLoginURL(request.getRequestURI()) %>">Sign in</a>
to include your name with greetings you post.</p>
<%
}
%>
<%
PersistenceManager pm = PMF.get().getPersistenceManager();
String query = "select from " + Greeting.class.getName() + " order by date desc range 0,5";
List<Greeting> greetings = (List<Greeting>) pm.newQuery(query).execute();
