private String filePath() {
		IWorkbench workbench = PlatformUI.getWorkbench();
		if(workbench == null)
			return null;
		IWorkbenchWindow workbenchWindow = workbench 
				.getActiveWorkbenchWindow();
		if(workbenchWindow == null)
			return null;
		IWorkbenchPage workbenchPage = workbenchWindow.getActivePage();
		if(workbenchPage == null)
			return null;
		IWorkbenchPart workbenchPart = workbenchPage.getActivePart();
		if(workbenchPart == null)
			return null;
		IWorkbenchPartSite workbenchPartSite = workbenchPart.getSite();
		if(workbenchPartSite == null)
			return null;
		IWorkbenchPage page = workbenchPartSite.getPage();
		if(page == null)
			return null;
		IEditorPart activeEditor = page.getActiveEditor();
		if(activeEditor == null)
			return null;
		IEditorInput editorInput = activeEditor.getEditorInput();
		if(editorInput == null)
			return null;
		IFile file = (IFile) editorInput.getAdapter(IFile.class);
		if (file == null)
			return null;
		return file.getRawLocation().toOSString();
	}