Java JComponent Container getRoot(Component comp)

Description

Returns the "root" of the component tree containint comp The root is defined as either the least ancestor of comp which is a Window , or the greatest ancestor of comp which is a Applet if no Window ancestors are found.

License

Open Source License

Parameter

Parameter	Description
comp	The component to search for a root

Return

The root of the component's tree, or null

Declaration

public static Component getRoot(Component comp)

Method Source Code


//package com.java2s;
/* AWTUtilities.java -- Common utility methods for AWT and Swing.
   Copyright (C) 2005, 2007  Free Software Foundation, Inc.
    /*w  w w .j  a va2  s  .c  o m*/
This file is part of GNU Classpath.
    
GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
    
GNU Classpath 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
General Public License for more details.
    
You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA.
    
Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
conditions of the GNU General Public License cover the whole
combination.
    
As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
modules, and to copy and distribute the resulting executable under
terms of your choice, provided that you also meet, for each linked
independent module, the terms and conditions of the license of that
module.  An independent module is a module which is not derived from
or based on this library.  If you modify this library, you may extend
this exception to your version of the library, but you are not
obligated to do so.  If you do not wish to do so, delete this
exception statement from your version. */

import java.applet.Applet;
import java.awt.Component;

import java.awt.Window;

public class Main {
    /**
     * Returns the "root" of the component tree containint <code>comp</code>
     * The root is defined as either the <em>least</em> ancestor of
     * <code>comp</code> which is a {@link Window}, or the <em>greatest</em>
     * ancestor of <code>comp</code> which is a {@link Applet} if no {@link
     * Window} ancestors are found.
     *
     * @param comp The component to search for a root
     *
     * @return The root of the component's tree, or <code>null</code>
     */
    public static Component getRoot(Component comp) {
        Applet app = null;
        Window win = null;

        while (comp != null) {
            if (win == null && comp instanceof Window)
                win = (Window) comp;
            else if (comp instanceof Applet)
                app = (Applet) comp;
            comp = comp.getParent();
        }

        if (win != null)
            return win;
        else
            return app;
    }
}