| /* |
| * 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; |
| } |
| } |
| } |
| } |
| } |