001    /*
002     * Copyright (c) 2006 Henri Sivonen
003     *
004     * Permission is hereby granted, free of charge, to any person obtaining a 
005     * copy of this software and associated documentation files (the "Software"), 
006     * to deal in the Software without restriction, including without limitation 
007     * the rights to use, copy, modify, merge, publish, distribute, sublicense, 
008     * and/or sell copies of the Software, and to permit persons to whom the 
009     * Software is furnished to do so, subject to the following conditions:
010     *
011     * The above copyright notice and this permission notice shall be included in 
012     * all copies or substantial portions of the Software.
013     *
014     * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
015     * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
016     * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 
017     * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
018     * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 
019     * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
020     * DEALINGS IN THE SOFTWARE.
021     */
022    
023    package fi.iki.hsivonen.xml.checker.table;
024    
025    import java.util.Comparator;
026    
027    /**
028     * Compares cells first by their <code>bottom</code> field and then by their 
029     * <code>left</code> field. The cells can never be equal.
030     * 
031     * @version $Id: VerticalCellComparator.java,v 1.5 2006/12/01 12:34:30 hsivonen Exp $
032     * @author hsivonen
033     */
034    final class VerticalCellComparator implements Comparator<Cell> {
035    
036        public static final VerticalCellComparator THE_INSTANCE = new VerticalCellComparator();
037        
038        private VerticalCellComparator() {
039            super();
040        }
041    
042        public final int compare(Cell cell0, Cell cell1) {
043            if (cell0.getBottom() < cell1.getBottom()) {
044                return -1;
045            } else if (cell0.getBottom() > cell1.getBottom()) {
046                return 1;
047            } else {
048                if (cell0.getLeft() < cell1.getLeft()) {
049                    return -1;
050                } else if (cell0.getLeft() > cell1.getLeft()) {
051                    return 1;
052                } else {
053                    throw new IllegalStateException("Two cells in effect cannot start on the same column, so this should never happen!");
054                }
055            }
056        }
057    }