Groovy is an agile dynamic language for the Java platform, defined as JSR 241. It has many features that were inspired by languages such as Python, Ruby, and Smalltalk, making them available to Java developers with a Java-like syntax. It interoperates seamlessly with any Java class, and can be compiled and interpreted without disturbing normal operations.
This latest release of JDeveloper provides integrated support for Groovy. You can use Groovy expressions for all sorts of declarative values, such as bind variables and attribute default values. You can use a Groovy script that returns true or false for declarative validation. You can also use Groovy expressions in error messages. You see examples of using Groovy expressions when these different topics are presented in this lesson and later lessons.
Groovy can simplify expressions and make them more concise in that it supports object access via dot-separated notation, so it supports syntax such as Empno instead of getAttribute(EMPNO).
You can find out more about Groovy at http://groovy.codehaus.org/ and http://radio.weblogs.com/0118231/2007/05/22.html#a829.
Note: Groovy is still a fairly new technology and is missing features such as code completion and debugging capabilities. This makes it difficult to use for large segments of code.