ADF_008：Groovy 介绍 （摘录+整理）

【Groovy】：An agile dynamic language for the Java Platform。

• is an agile and dynamic language for the Java Virtual Machine


• builds upon the strengths of Java but has additional power features inspired by languages like Python, Ruby and Smalltalk


• makes modern programming features available to Java developers with almost-zero learning curve


• supports Domain-Specific Languages and other compact syntax so your code becomes easy to read and maintain


• makes writing shell and build scripts easy with its powerful processing primitives, OO abilities and an Ant DSL


• increases developer productivity by reducing scaffolding code when developing web, GUI, database or console applications


• simplifies testing by supporting unit testing and mocking out-of-the-box


• seamlessly integrates with all existing Java objects and libraries


• compiles straight to Java bytecode so you can use it anywhere you can use Java


• Java Specification Request 241 (JSR 241)

Groovy运行在JVM中，并且能够使用Java Libraries，类似Java语言的语法，严格的讲是Java语言的超集。
Groovy是在Runtime时解析，可以用来定制化，比如把定制化信息保存在MDS中，让不同的用户使用不同的业务规则。
Oracle ADF 提供了以下声明式的方式使用Groovy:
  （1） 设置EO或VO的Attribute值
  （2） 定义在EO的Attribute上的验证规则
  （3） 错误消息
  （4） 定义在VO上的绑定变量
  （5） 定义在VO上的Transient Attribute的验证

参考文献：
1. http://groovy.codehaus.org/
2. http://www.ibm.com/developerworks/cn/java/j-pg/
3. http://www.ibm.com/developerworks/cn/java/j-pg02179.html