Bug 127746 [build path] Build Path action "no actions available" should be disabled
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/buildpaths/newsourcepage/GenerateBuildPathActionGroup.java
protected IPath getOutputLocation(IJavaProject javaProject) {
    		try {
    			return javaProject.getOutputLocation();		
    		} catch (CoreException e) {
    			IProject project= javaProject.getProject();
    			IPath projPath= project.getFullPath();
    			return projPath.append(PreferenceConstants.getPreferenceStore().getString(PreferenceConstants.SRCBIN_BINNAME));
    		}
    	}
    	
		/**
		 * {@inheritDoc}
		 */
		public void selectionChanged(SelectionChangedEvent event) {
            ISelection selection = event.getSelection();
            if (selection instanceof IStructuredSelection) {
    			setEnabled(selectionChanged((IStructuredSelection) selection));
            } else {
    			setEnabled(selectionChanged(StructuredSelection.EMPTY));
            }
		}
		
		public abstract boolean selectionChanged(IStructuredSelection selection);
    }
		
    public static class AddSourceFolderAction extends OpenBuildPathWizardAction {