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GATE - general achitecture for text engineering - is open source software capable of solving almost any text processing problem. This artifact enables you to embed the core GATE Embedded with its essential dependencies. You will able to use the GATE Embedded API and load and store GATE XML documents. This artifact is the perfect dependency for CREOLE plugins or for applications that need to customize the GATE dependencies due to confict with their own dependencies or for lower footprint.

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/*
 *  Copyright 1994-2009 Sun Microsystems, Inc. All Rights Reserved.
 *  Under BSD licence, LGPL compatible.
 *
 *  This file is part of GATE (see http://gate.ac.uk/), and is free
 *  software, licenced under the GNU Library General Public License,
 *  Version 2, June 1991 (in the distribution as file licence.html,
 *  and also available at http://gate.ac.uk/gate/licence.html).
 *
 *  From Sun forums:
 *  
 *  Swing [Archive] - Block JFrame and JDialog with JGlassPane
 *
 *  Retrieved by Thomas Heitz - 03 july 2009.
 *
 *  $Id$
 */

package gate.swing;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

/**
 * A Panel that can be blocked.
 * 

 * Just set an instance of this class as the glassPane
 * of your JFrame and call block() as needed.
 */
@SuppressWarnings("serial")
public class BlockingGlassPane extends JPanel {

  private int        blockCount = 0;
  private BlockMouse blockMouse = new BlockMouse();
  private BlockKeys  blockKeys  = new BlockKeys();

  /**
   * Constructor.
   */
  public BlockingGlassPane() {
    setVisible(false);
    setOpaque (false);

    addMouseListener(blockMouse);
  }

  /**
   * Start or end blocking.
   *
   * @param block   should blocking be started or ended
   */
  public void block(boolean block) {
    if (block) {
      if (blockCount == 0) {
        setVisible(true);

        setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));

        FocusManager.getCurrentManager().addKeyEventDispatcher(blockKeys);
      }
      blockCount++;
    } else {
      blockCount--;
      if (blockCount == 0) {
        FocusManager.getCurrentManager().removeKeyEventDispatcher(blockKeys);

        setCursor(Cursor.getDefaultCursor());

        setVisible(false);
      }
    }
  }

  /**
   * Test if this glasspane is blocked.
   *
   * @return    true if currently blocked
   */
  public boolean isBlocked() {
    return blockCount > 0;
  }

  /**
   * The key dispatcher to block the keys.
   */
  private class BlockKeys implements KeyEventDispatcher {
    @Override
    public boolean dispatchKeyEvent(KeyEvent ev) {
      Component source = ev.getComponent();
      if (source != null &&
          SwingUtilities.isDescendingFrom(source, getParent())) {
        Toolkit.getDefaultToolkit().beep();
        ev.consume();
        return true;
      }
      return false;
    }
  }

  /**
   * The mouse listener used to block the mouse.
   */
  private class BlockMouse extends MouseAdapter {
    @Override
    public void mouseClicked(MouseEvent ev) {
      Toolkit.getDefaultToolkit().beep();
    }
  }
}