// error tree view initialization must be invoked from event dispatch thread
  private void openMessageView() {
    if (isHeadlessMode()) {
      return;
    }
    if (myIndicator.isCanceled()) {
      return;
    }

    final JComponent component;
    synchronized (myMessageViewLock) {
      if (myErrorTreeView != null) {
        return;
      }
      myErrorTreeView = new CompilerErrorTreeView(myProject, myRestartWork);

      myErrorTreeView.setProcessController(
          new NewErrorTreeViewPanel.ProcessController() {
            @Override
            public void stopProcess() {
              cancel();
            }

            @Override
            public boolean isProcessStopped() {
              return !myIndicator.isRunning();
            }
          });
      component = myErrorTreeView.getComponent();
    }

    final MessageView messageView = MessageView.SERVICE.getInstance(myProject);
    final Content content =
        ContentFactory.SERVICE.getInstance().createContent(component, myContentName, true);
    CONTENT_ID_KEY.set(content, myContentId);
    SESSION_ID_KEY.set(content, mySessionId);
    messageView.getContentManager().addContent(content);
    myCloseListener.setContent(content, messageView.getContentManager());
    removeAllContents(myProject, content);
    messageView.getContentManager().setSelectedContent(content);
  }
  /** @return can be null if user cancelled operation */
  @Nullable
  public static AntBuildMessageView openBuildMessageView(
      Project project, AntBuildFileBase buildFile, String[] targets) {
    final VirtualFile antFile = buildFile.getVirtualFile();
    if (!LOG.assertTrue(antFile != null)) {
      return null;
    }

    // check if there are running instances of the same build file

    MessageView ijMessageView = MessageView.SERVICE.getInstance(project);
    Content[] contents = ijMessageView.getContentManager().getContents();
    for (Content content : contents) {
      if (content.isPinned()) {
        continue;
      }
      AntBuildMessageView buildMessageView = content.getUserData(KEY);
      if (buildMessageView == null) {
        continue;
      }

      if (!antFile.equals(buildMessageView.getBuildFile().getVirtualFile())) {
        continue;
      }

      if (buildMessageView.isStopped()) {
        ijMessageView.getContentManager().removeContent(content, true);
        continue;
      }

      int result =
          Messages.showYesNoCancelDialog(
              AntBundle.message("ant.is.active.terminate.confirmation.text"),
              AntBundle.message("starting.ant.build.dialog.title"),
              Messages.getQuestionIcon());

      switch (result) {
        case 0: // yes
          buildMessageView.stopProcess();
          ijMessageView.getContentManager().removeContent(content, true);
          continue;
        case 1: // no
          continue;
        default: // cancel
          return null;
      }
    }

    final AntBuildMessageView messageView = new AntBuildMessageView(project, buildFile, targets);
    String contentName = buildFile.getPresentableName();
    contentName = BUILD_CONTENT_NAME + " (" + contentName + ")";

    final Content content =
        ContentFactory.SERVICE
            .getInstance()
            .createContent(messageView.getComponent(), contentName, true);
    content.putUserData(KEY, messageView);
    ijMessageView.getContentManager().addContent(content);
    ijMessageView.getContentManager().setSelectedContent(content);
    content.setDisposer(
        new Disposable() {
          @Override
          public void dispose() {
            Disposer.dispose(messageView.myAlarm);
          }
        });
    new CloseListener(content, ijMessageView.getContentManager(), project);
    // Do not inline next two variabled. Seeking for NPE.
    ToolWindow messageToolWindow =
        ToolWindowManager.getInstance(project).getToolWindow(ToolWindowId.MESSAGES_WINDOW);
    messageToolWindow.activate(null, false);
    return messageView;
  }