BeanIntegerComparator.java

/**********************************************************************************
 * $URL: https://source.sakaiproject.org/svn/sam/trunk/samigo-app/src/java/org/sakaiproject/tool/assessment/util/BeanIntegerComparator.java $
 * $Id: BeanIntegerComparator.java 106463 2012-04-02 12:20:09Z david.horwitz@uct.ac.za $
 ***********************************************************************************
 *
 * Copyright (c) 2005, 2006, 2008 The Sakai Foundation
 *
 * Licensed under the Educational Community License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *       http://www.opensource.org/licenses/ECL-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 **********************************************************************************/


package org.sakaiproject.tool.assessment.util;

import java.util.Map;

/**
 * DOCUMENTATION PENDING
 *
 * @author $author$
 * @version $Id: BeanIntegerComparator.java 106463 2012-04-02 12:20:09Z david.horwitz@uct.ac.za $
 */
public class BeanIntegerComparator
  extends BeanSortComparator
{
  private String propertyName;

  /**
   * The only public constructor.  Requires a valid property name for a a Java
   * Bean as a sole parameter.
   *
   * @param propertyName the property name for Java Bean to sort by
   */
  public BeanIntegerComparator(String propertyName)
  {
    this.propertyName = propertyName;
  }

  /**
   * Creates a new BeanIntegerComparator object.
   */
  protected BeanIntegerComparator()
  {
  }
  ;

  /**
   * standard compare method
   *
   * @param o1 object
   * @param o2 object
   *
   * @return lt, eq, gt zero depending on whether o1 numerically lt,eq,gt o2
   *
   * @throws java.lang.UnsupportedOperationException DOCUMENTATION PENDING
   */
  public int compare(Object o1, Object o2)
  {
	  Map m1 = describeBean(o1);
	  Map m2 = describeBean(o2);
	  String s1 = (String) m1.get(propertyName);
	  String s2 = (String) m2.get(propertyName);
	  Integer i1 = null;
	  Integer i2 = null;
	  boolean firstIntegerValid = true;
	  boolean secondIntegerValid = true;

	  try
	  {
		  i1 = Integer.valueOf(s1);
	  }
	  catch (NumberFormatException e)
	  {
		  firstIntegerValid = false;
	  }

	  try
	  {
		  i2 = Integer.valueOf(s2);
	  }
	  catch (NumberFormatException e)
	  {
		  secondIntegerValid = false;
	  }

	  int returnValue=0;
	  if (firstIntegerValid && secondIntegerValid) {
		  if (i1 != null) {
			  returnValue = i1.compareTo(i2);
		  }
	  }
	  if (firstIntegerValid && !secondIntegerValid) returnValue = 1;
	  if (!firstIntegerValid && secondIntegerValid) returnValue = -1;
	  if (!firstIntegerValid && !secondIntegerValid) returnValue = 0;

	  return returnValue;  
  }
}