Launch an external diff tool like WinMerge in Eclipse
Eclipse comes with an internal diff / compare editor, but if you prefer a third-party one, this plugin opens an external merge or diff tool for you.
After you open two versions of a file in the internal eclipse compare editor, this plugin either opens an external diff tool automatically or you can choose that this plugin opens the external diff tool after you press a button in the toolbar of the internal compare editor.
Furthermore the plugin can (optional) format java code before the compare. ...
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.