There is also the Jersey Test Framework (http://jersey.java.net/nonav/documentation/latest/user-guide.html#test-framework) but as Johan already mentioned the REST-assured framework I'd also recommend this framework - it has some nice featues like a DSL like syntax, XPath and Schema validation, easy file upload and using Groovy Lambda Expressions to search through returned JSON structures..
I have written two articles..
- the first one compares REST-assured and Jersey-Test-Framework (http://www.hascode.com/2011/09/rest-assured-vs-jersey-test-framework-testing-your-restful-web-services/),
- the second explores the features of the REST-assured framework against a given REST service (http://www.hascode.com/2011/10/testing-restful-web-services-made-easy-using-the-rest-assured-framework/)
