the swt faq - eclipse
.eclipse.swt.SWTException: Invalid thread access"...keyboard shortcuts on Windows, Mac OS X, Linux?...are forcing your launch to use a 64-bit VM. ...
according to maven
You can then attach to the running tests using Eclipse. You can setup a "Remote Java Application" launch configuration via the menu command "Run" > "...
Debug/FAQ - Eclipsepedia
If it does make sure that eclipse has TCP access to 'localhost', as ...'localhost' than the debugger cannot resolve connecting to the local VM via...