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Google Eclipse插件：App Engine ORM增强了吗？

[英]Google Eclipse Plugin: App Engine ORM Enhancement?

原文 2012-08-22 02:26:08 9 1 java/ google-app-engine/ gwt/ orm/ google-eclipse-plugin

I just installed the Google Plugin for Eclipse and created my first Web Application Project using the built-in wizard. 我刚刚安装了Eclipse的Google插件，并使用内置向导创建了我的第一个Web应用程序项目。 Going to MyProject >> Properties >> Google >> App Engine >> ORM I see a listbox and a section of text that reads: 转到MyProject >> Properties >> Google >> App Engine >> ORM我看到一个列表框和一段文本，内容为：

Enhance the following classes for usage with ORM: 增强以下类以用于ORM：

Searching for this online, the only documentation I can find states that GAE, which uses JDO (DataNucleus), requires post-compilation "enhancement" (which I assume means bytecode generation?!?), and that this dialog gives you the ability to specify which classes get "enhanced"? 在网上搜索该文档，我只能找到使用JDO（DataNucleus）的GAE，需要进行编译后的“增强”（我认为这意味着生成字节码？！？），并且此对话框使您能够指定哪些类得到“增强”？

Still confused by what this "enhancement" stuff is all about, and why its necessary 仍然对这些“增强”内容是什么及其为何必要感到困惑
Confused about what classes I would want to select for enhancement 对于我想选择哪些类进行增强感到困惑
Also, I assume this enhancement only occurs when building/deploying my app from inside Eclipse, how do I access this "enhancement" functionality from inside my Ant build? 另外，我假设此增强功能仅在从Eclipse内部构建/部署我的应用程序时发生，如何从我的Ant构建内部访问此“增强”功能？

Thanks in advance! 提前致谢！

1 个解决方案

JDO class enhancement gives data classes ability to detect "dirty" fields, ie fields that have been changed since data was last loaded. JDO类增强使数据类能够检测“脏”字段，即自上次加载数据以来已更改的字段。 This is needed to efficiently decide which objects need saving. 这是有效决定需要保存哪些对象的必要条件。
The JDO data classes , eg the ones that get mapped to data in the database. JDO数据类，例如那些映射到数据库中数据的类。
GAE SDK includes several ant tasks related to GAE development, including one to do JDO enhancement. GAE SDK包含与GAE开发相关的多项ant任务，其中一项是执行JDO增强。