Freefactor is a Java refactoring framework. It consists of a tool-independent refactoring system and an interface to allow it to be integrated with other tools. Currently a prototype Java-based tool is provided as well as bindings for Emacs. It has been released under the GNU General Public License.Please visit the Sourceforge project page.
You'll need to have JDK 1.3 or better (not just JRE if you want to be able to compile stuff :). Also you'll need to have JAVA_HOME set correctly. For the Emacs tool you'll need Emacs 20 or better and JDE 2.2.9 or better. Be warned that everything is very beta, especially the Emacs port.