IconComparator.java

/*  Copyright (C) 2003-2012 JabRef contributors.
    This program 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 of the License, or
    (at your option) any later version.

    This program 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 this program; if not, write to the Free Software Foundation, Inc.,
    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
package net.sf.jabref.gui;

import net.sf.jabref.BibtexEntry;

import java.util.Comparator;

/**
 * Comparator that handles icon columns. 
 */
public class IconComparator implements Comparator<BibtexEntry> {

    private String[] fields;

    public IconComparator(String[] fields) {
        this.fields = fields;
    }

    public int compare(BibtexEntry e1, BibtexEntry e2) {

        for (int i=0; i<fields.length; i++) {
            String val1 = e1.getField(fields[i]);
            String val2 = e2.getField(fields[i]);
			if (val1 == null) {
				if (val2 != null) {
					return 1;
				} else {
					// continue loop and check for next field
				}
			} else {
				if (val2 == null) {
					return -1;
				} else {
					// val1 is not null AND val2 is not null
					int compareToRes = val1.compareTo(val2);
					if (compareToRes != 0) {
						return compareToRes;
					} else {
						// continue loop as current two values are equal
					}
				}
			}
		}
        return 0;
    }

}