Google App Engine 可让您在 Google 的基础架构上运行您的网络应用程序。App Engine 应用程序易于构建和维护，并可根据您的访问量和数据存储需要的增长轻松扩展。使用 Google App Engine，将不再需要维护服务器：您只需上传您的应用程序，它便可立即为您的用户提供服务.
下载:Google App Engine Java SDK 1.3.0App Engine Java SDK - Release Notes
Version 1.3.0 - December 14, 2009
- Adds support for the new Blobstore API
- New com.google.appengine.runtime.{version,environment} system properties (and a SystemProperty accessor class)
- New sample applications for GWT 2.0
- Optimizations for many reflection operations
- Incorrect exception for multiple fields of same type
- http://code.google.com/p/datanucleus-appengine/issues/detail?id=172
- Non-persistent base classes do not work
- http://code.google.com/p/datanucleus-appengine/issues/detail?id=169