Java Tutorial/Swing/Frame

Get all windows with Frame.getFrames()

import java.awt.Frame;
import java.awt.Window;
import javax.swing.JDialog;
import javax.swing.JFrame;
public class MainClass {
  public static void main(String[] args) {
    JDialog d1 = new JDialog((JFrame) null, "Dialog 1");
    d1.setName("Dialog 1");
    JDialog d2 = new JDialog((Window) null, "Dialog 2");
    d2.setName("Dialog 2");
    Frame f = new Frame();
    f.setName("Frame 1");
    Window w1 = new Window(f);
    w1.setName("Window 1");
    Window w2 = new Window(null);
    w2.setName("Window 2");
    System.out.println("FRAME WINDOWS");
    Frame[] frames = Frame.getFrames();
    for (Frame frame : frames)
      System.out.println(frame.getName() + ": " + frame.getClass());
  }
}

Get Owning Frame for Component

/*
 * Copyright (C) 2001-2004 Colin Bell
 * colbell@users.sourceforge.net
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

import java.awt.ruponent;
import java.awt.Frame;
import javax.swing.SwingUtilities;
/**
 * Common GUI utilities accessed via static methods.
 * 
 * @author 
 */
public class GUIUtils {
  /**
   * Return the owning <CODE>Frame</CODE> for the passed component of <CODE>null</CODE>
   * if it doesn"t have one.
   * 
   * @throws IllegalArgumentException
   *           If <TT>wind</TT> is <TT>null</TT>.
   */
  public static Frame getOwningFrame(Component comp) {
    if (comp == null) {
      throw new IllegalArgumentException("null Component passed");
    }
    if (comp instanceof Frame) {
      return (Frame) comp;
    }
    return getOwningFrame(SwingUtilities.windowForComponent(comp));
  }
}

Set Frame Location Relative To

import javax.swing.*;
import java.awt.*;
/**
 * @author Adrian BER (beradrian@yahoo.ru)
 */
public class UIUtilities {

    public static void setFrameLocationRelativeTo(JFrame f, Component c) {
        if (c == null) {
            // Setting the position of the dialog on the center of the screen
            // in 1.4 should be replaced by
//             f.setLocationRelativeTo(null);
            Dimension d = Toolkit.getDefaultToolkit().getScreenSize();
            f.setLocation((int)d.getWidth()/2 - (int)f.getPreferredSize().getWidth()/2,
                    (int)d.getHeight()/2 - (int)f.getPreferredSize().getHeight()/2);
        }
    }
}