Launch an external diff tool like WinMerge in Eclipse
...Furthermore the plugin can (optional) format java code before the compare. This simplifies the compare if the code of 2 versions of a file is different formatted.
External diff Tool is an Eclipse plugin that allows the launch of an external diff tool for file compares rather than the default built-in Eclipse diff tool. This plugin doesn't replace the built-in Eclipse tool. It only adds a new menu item to the GUI.