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	/*
	* Copyright (c) 2000, 2008, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code 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
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/
	package javax.swing;

	import java.util.Comparator;
	import java.util.LinkedList;
	import java.util.ListIterator;
	import java.awt.Component;
	import java.awt.ComponentOrientation;
	import java.awt.Window;


	/**
	* Comparator which attempts to sort Components based on their size and
	* position. Code adapted from original javax.swing.DefaultFocusManager
	* implementation.
	*
	* @author David Mendenhall
	*/
	final class LayoutComparator implements Comparator<Component>, java.io.Serializable {

	private static final int ROW_TOLERANCE = 10;

	private boolean horizontal = true;
	private boolean leftToRight = true;

	void setComponentOrientation(ComponentOrientation orientation) {
	horizontal = orientation.isHorizontal();
	leftToRight = orientation.isLeftToRight();
	}

	public int compare(Component a, Component b) {
	if (a == b) {
	return 0;
	}

	// Row/Column algorithm only applies to siblings. If 'a' and 'b'
	// aren't siblings, then we need to find their most inferior
	// ancestors which share a parent. Compute the ancestory lists for
	// each Component and then search from the Window down until the
	// hierarchy branches.
	if (a.getParent() != b.getParent()) {
	LinkedList<Component> aAncestory = new LinkedList<Component>();

	for(; a != null; a = a.getParent()) {
	aAncestory.add(a);
	if (a instanceof Window) {
	break;
	}
	}
	if (a == null) {
	// 'a' is not part of a Window hierarchy. Can't cope.
	throw new ClassCastException();
	}

	LinkedList<Component> bAncestory = new LinkedList<Component>();

	for(; b != null; b = b.getParent()) {
	bAncestory.add(b);
	if (b instanceof Window) {
	break;
	}
	}
	if (b == null) {
	// 'b' is not part of a Window hierarchy. Can't cope.
	throw new ClassCastException();
	}

	for (ListIterator<Component>
	aIter = aAncestory.listIterator(aAncestory.size()),
	bIter = bAncestory.listIterator(bAncestory.size()); ;) {
	if (aIter.hasPrevious()) {
	a = aIter.previous();
	} else {
	// a is an ancestor of b
	return -1;
	}

	if (bIter.hasPrevious()) {
	b = bIter.previous();
	} else {
	// b is an ancestor of a
	return 1;
	}

	if (a != b) {
	break;
	}
	}
	}

	int ax = a.getX(), ay = a.getY(), bx = b.getX(), by = b.getY();

	int zOrder = a.getParent().getComponentZOrder(a) - b.getParent().getComponentZOrder(b);
	if (horizontal) {
	if (leftToRight) {

	// LT - Western Europe (optional for Japanese, Chinese, Korean)

	if (Math.abs(ay - by) < ROW_TOLERANCE) {
	return (ax < bx) ? -1 : ((ax > bx) ? 1 : zOrder);
	} else {
	return (ay < by) ? -1 : 1;
	}
	} else { // !leftToRight

	// RT - Middle East (Arabic, Hebrew)

	if (Math.abs(ay - by) < ROW_TOLERANCE) {
	return (ax > bx) ? -1 : ((ax < bx) ? 1 : zOrder);
	} else {
	return (ay < by) ? -1 : 1;
	}
	}
	} else { // !horizontal
	if (leftToRight) {

	// TL - Mongolian

	if (Math.abs(ax - bx) < ROW_TOLERANCE) {
	return (ay < by) ? -1 : ((ay > by) ? 1 : zOrder);
	} else {
	return (ax < bx) ? -1 : 1;
	}
	} else { // !leftToRight

	// TR - Japanese, Chinese, Korean

	if (Math.abs(ax - bx) < ROW_TOLERANCE) {
	return (ay < by) ? -1 : ((ay > by) ? 1 : zOrder);
	} else {
	return (ax > bx) ? -1 : 1;
	}
	}
	}
	}
	}

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