Now I am doing some code basing on regex in Groovy. But for creation and testing my regexes I use books referencing to Java regex engine and Java-oriented http://www.regexplanet.com/advanced/java/index.html.
And I am a bit afraid - Is Groovy regex engine really the same as Java one? I know that they are very close. But have they some differences nevertheless? If you know the answer - can you kindly give me some reference on the subject?