private boolean processProxyModeEvent(XEvent ev) {
    if (getProxyModeSourceWindow() == 0) {
      return false;
    }

    if (ev.get_type() != (int) XConstants.ClientMessage) {
      return false;
    }

    if (logger.isLoggable(PlatformLogger.Level.FINEST)) {
      logger.finest("        proxyModeSourceWindow=" + getProxyModeSourceWindow() + " ev=" + ev);
    }

    XClientMessageEvent xclient = ev.get_xclient();

    Iterator dragProtocols = XDragAndDropProtocols.getDragSourceProtocols();
    while (dragProtocols.hasNext()) {
      XDragSourceProtocol dragProtocol = (XDragSourceProtocol) dragProtocols.next();
      if (dragProtocol.processProxyModeEvent(xclient, getProxyModeSourceWindow())) {
        return true;
      }
    }

    return false;
  }
  private void doUpdateTargetWindow(long subwindow, long time) {
    long clientWindow = 0;
    long proxyWindow = 0;
    XDragSourceProtocol protocol = null;
    boolean isReceiver = false;

    if (subwindow != 0) {
      clientWindow = findClientWindow(subwindow);
    }

    if (clientWindow != 0) {
      Iterator dragProtocols = XDragAndDropProtocols.getDragSourceProtocols();
      while (dragProtocols.hasNext()) {
        XDragSourceProtocol dragProtocol = (XDragSourceProtocol) dragProtocols.next();
        if (dragProtocol.attachTargetWindow(clientWindow, time)) {
          protocol = dragProtocol;
          break;
        }
      }
    }

    /* Update the global state. */
    dragProtocol = protocol;
    targetAction = DnDConstants.ACTION_NONE;
    targetRootSubwindow = subwindow;
  }
  /** The caller must own awtLock. */
  public void cleanup(long time) {
    if (dndInProgress) {
      if (dragProtocol != null) {
        dragProtocol.sendLeaveMessage(time);
      }

      if (targetAction != DnDConstants.ACTION_NONE) {
        dragExit(xRoot, yRoot);
      }

      dragDropFinished(false, DnDConstants.ACTION_NONE, xRoot, yRoot);
    }

    Iterator dragProtocols = XDragAndDropProtocols.getDragSourceProtocols();
    while (dragProtocols.hasNext()) {
      XDragSourceProtocol dragProtocol = (XDragSourceProtocol) dragProtocols.next();
      try {
        dragProtocol.cleanup();
      } catch (XException xe) {
        // Ignore the exception.
      }
    }

    dndInProgress = false;
    dragInProgress = false;
    dragRootWindow = 0;
    sourceFormats = null;
    sourceActions = DnDConstants.ACTION_NONE;
    sourceAction = DnDConstants.ACTION_NONE;
    eventState = 0;
    xRoot = 0;
    yRoot = 0;

    cleanupTargetInfo();

    removeDnDGrab(time);
  }
  protected void startDrag(Transferable transferable, long[] formats, Map formatMap) {
    Component component = getTrigger().getComponent();
    Component c = null;
    XWindowPeer wpeer = null;

    for (c = component;
        c != null && !(c instanceof Window);
        c = AWTAccessor.getComponentAccessor().getParent(c)) ;

    if (c instanceof Window) {
      wpeer = (XWindowPeer) c.getPeer();
    }

    if (wpeer == null) {
      throw new InvalidDnDOperationException("Cannot find top-level for the drag source component");
    }

    long xcursor = 0;
    long rootWindow = 0;
    long dragWindow = 0;
    long timeStamp = 0;

    /* Retrieve the X cursor for the drag operation. */
    {
      Cursor cursor = getCursor();
      if (cursor != null) {
        xcursor = XGlobalCursorManager.getCursor(cursor);
      }
    }

    XToolkit.awtLock();
    try {
      if (proxyModeSourceWindow != 0) {
        throw new InvalidDnDOperationException("Proxy drag in progress");
      }
      if (dndInProgress) {
        throw new InvalidDnDOperationException("Drag in progress");
      }

      /* Determine the root window for the drag operation. */
      {
        long screen = XlibWrapper.XScreenNumberOfScreen(wpeer.getScreen());
        rootWindow = XlibWrapper.RootWindow(XToolkit.getDisplay(), screen);
      }

      dragWindow = XWindow.getXAWTRootWindow().getWindow();

      timeStamp = XToolkit.getCurrentServerTime();

      int dropActions = getDragSourceContext().getSourceActions();

      Iterator dragProtocols = XDragAndDropProtocols.getDragSourceProtocols();
      while (dragProtocols.hasNext()) {
        XDragSourceProtocol dragProtocol = (XDragSourceProtocol) dragProtocols.next();
        try {
          dragProtocol.initializeDrag(
              dropActions, transferable,
              formatMap, formats);
        } catch (XException xe) {
          throw (InvalidDnDOperationException) new InvalidDnDOperationException().initCause(xe);
        }
      }

      /* Install X grabs. */
      {
        int status;
        XWindowAttributes wattr = new XWindowAttributes();
        try {
          status = XlibWrapper.XGetWindowAttributes(XToolkit.getDisplay(), rootWindow, wattr.pData);

          if (status == 0) {
            throw new InvalidDnDOperationException("XGetWindowAttributes failed");
          }

          rootEventMask = wattr.get_your_event_mask();

          XlibWrapper.XSelectInput(
              XToolkit.getDisplay(), rootWindow, rootEventMask | ROOT_EVENT_MASK);
        } finally {
          wattr.dispose();
        }

        XBaseWindow.ungrabInput();

        status =
            XlibWrapper.XGrabPointer(
                XToolkit.getDisplay(),
                rootWindow,
                0,
                GRAB_EVENT_MASK,
                XConstants.GrabModeAsync,
                XConstants.GrabModeAsync,
                XConstants.None,
                xcursor,
                timeStamp);

        if (status != XConstants.GrabSuccess) {
          cleanup(timeStamp);
          throwGrabFailureException("Cannot grab pointer", status);
          return;
        }

        status =
            XlibWrapper.XGrabKeyboard(
                XToolkit.getDisplay(),
                rootWindow,
                0,
                XConstants.GrabModeAsync,
                XConstants.GrabModeAsync,
                timeStamp);

        if (status != XConstants.GrabSuccess) {
          cleanup(timeStamp);
          throwGrabFailureException("Cannot grab keyboard", status);
          return;
        }
      }

      /* Update the global state. */
      dndInProgress = true;
      dragInProgress = true;
      dragRootWindow = rootWindow;
      sourceActions = dropActions;
      sourceFormats = formats;
    } finally {
      XToolkit.awtUnlock();
    }

    /* This implementation doesn't use native context */
    setNativeContext(0);

    SunDropTargetContextPeer.setCurrentJVMLocalSourceTransferable(transferable);
  }