view java/src/uk/ac/qmul/eecs/ccmi/diagrammodel/DiagramElementComparator.java @ 0:78b7fc5391a2

first import, outcome of NIME 2014 hackaton

/*  
 CCmI Editor - A Collaborative Cross-Modal Diagram Editing Tool
  
 Copyright (C) 2011  Queen Mary University of London (http://ccmi.eecs.qmul.ac.uk/)

 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 3 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, see <http://www.gnu.org/licenses/>.
*/
package uk.ac.qmul.eecs.ccmi.diagrammodel;

import java.util.Comparator;

/**
 * A Comparator for diagram elements. The elements are ordered by their id.  
 *
 * @see DiagramElement#getId()
 */
public class DiagramElementComparator implements Comparator<DiagramElement> {
	public static DiagramElementComparator getInstance(){
		if(comparator == null)
			comparator = new DiagramElementComparator();
		return comparator;
	}
	
	@Override
	public int compare(DiagramElement de1, DiagramElement de2) {
		if(de1.getId() == de2.getId())
			return 0;
		else if(de1.getId() < de2.getId())
			return -1;
		else 
			return 1;
	}	

	private static DiagramElementComparator comparator;
}