private void doRefactor() {
    if (myTree.isValid()) {
      myDiffPanel.doExtract();
      close();
      return;
    }
    if (Messages.showYesNoDialog(myProject,
                                 JavaRefactoringBundle.message("project.files.have.been.changed"),
                                 JavaRefactoringBundle.message("re.run.refactoring"), null) == Messages.YES) {
      close();
      myDiffPanel.tryExtractAgain();
    }
  }
private void doRefactor()