/* -*- Mode: Java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (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.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Mozilla Communicator client code, released
 * March 31, 1998.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Patrick C. Beard <beard@netscape.com>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

import java.util.Enumeration;
import java.util.Hashtable;

/**
 * Provides a simple way to tally the occurrence of unique objects.
 */
public class Histogram {
	private static class Bin {
		int count = 0;
	};

	private Hashtable bins = new Hashtable();
	
	public void record(Object object) {
		Bin bin = (Bin) bins.get(object);
		if (bin == null) {
			bin = new Bin();
			bins.put(object, bin);
		}
		++bin.count;
	}
	
	public Object[] objects() {
		int count = bins.size();
		Object[] objects = new Object[count];
		Enumeration e = bins.keys();
		while (e.hasMoreElements())
			objects[--count] = e.nextElement();
		return objects;
	}
	
	public int count(Object object) {
		Bin bin = (Bin) bins.get(object);
		if (bin != null)
			return bin.count;
		else
			return 0;
	}
}