Utils.java Source code

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Here is the source code for Utils.java

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/*
 * $Id: WindowUtils.java,v 1.16 2009/05/25 16:37:52 kschaefe Exp $
 *
 * Copyright 2004 Sun Microsystems, Inc., 4150 Network Circle,
 * Santa Clara, California 95054, U.S.A. All rights reserved.
 *
 * 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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

import java.awt.GraphicsConfiguration;
import java.awt.GraphicsEnvironment;
import java.awt.Insets;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Toolkit;
import java.awt.Window;

/**
 * Encapsulates various utilities for windows (ie: <code>Frame</code> and
 * <code>Dialog</code> objects and descendants, in particular).
 *
 * @author Richard Bair
 */
public class Utils {
    public static Point getPointForCentering(Window window) {
        Rectangle usableBounds = getUsableDeviceBounds(window);
        int screenWidth = usableBounds.width;
        int screenHeight = usableBounds.height;
        int width = window.getWidth();
        int height = window.getHeight();

        return new Point(((screenWidth - width) / 2) + usableBounds.x,
                ((screenHeight - height) / 2) + usableBounds.y);
    }

    /**
     * <p>
     * Returns the <code>Point</code> at which a window should be placed to
     * center that window on the screen.
     * </p>
     * <p>
     * Some thought was taken as to whether to implement a method such as this,
     * or to simply make a method that, given a window, will center it.  It was
     * decided that it is better to not alter an object within a method.
     * </p>
     *
     * @param window The window to calculate the center point for.  This object
     *               can not be null.
     *
     * @return the <code>Point</code> at which the window should be placed to
     *         center that window on the screen.
     */

    private static Rectangle getUsableDeviceBounds(Window window) {
        Window owner = window.getOwner();
        GraphicsConfiguration gc = null;

        if (owner == null) {
            gc = GraphicsEnvironment.getLocalGraphicsEnvironment().getDefaultScreenDevice()
                    .getDefaultConfiguration();
        } else {
            gc = owner.getGraphicsConfiguration();
        }

        Insets insets = Toolkit.getDefaultToolkit().getScreenInsets(gc);
        Rectangle bounds = gc.getBounds();
        bounds.x += insets.left;
        bounds.y += insets.top;
        bounds.width -= (insets.left + insets.right);
        bounds.height -= (insets.top + insets.bottom);

        return bounds;
    }
}