/*
 * Copyright (c) 2016 Vivid Solutions.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * and Eclipse Distribution License v. 1.0 which accompanies this distribution.
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at
 *
 * http://www.eclipse.org/org/documents/edl-v10.php.
 */
package org.locationtech.jts.util;

import java.util.HashMap;
import java.util.Map;

/**
 * Counts occurrences of objects.
 * 
 * @author Martin Davis
 *
 */
public class ObjectCounter 
{

  private Map counts = new HashMap();
  
  public ObjectCounter() {
  }

  public void add(Object o)
  {
    Counter counter = (Counter) counts.get(o);
    if (counter == null)
      counts.put(o, new Counter(1));
    else
      counter.increment();
  }
  
  // TODO: add remove(Object o)
  
  public int count(Object o)
  {
    Counter counter = (Counter) counts.get(o);
    if (counter == null)
      return 0;
    else
      return counter.count();
   
  }
  private static class Counter
  {
    int count = 0;
    
    public Counter()
    {
      
    }
    
    public Counter(int count)
    {
      this.count = count;
    }
    
    public int count()
    {
      return count;
    }
    
    public void increment()
    {
      count++;
    }
  }
}