FloatHistoryCache.java

/*
 * Tigase Jabber/XMPP Server
 * Copyright (C) 2004-2012 "Artur Hefczyc" <artur.hefczyc@tigase.org>
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, version 3 of the License.
 * 
 * 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 Affero General Public License for more details.
 * 
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. Look for COPYING file in the top folder.
 * If not, see http://www.gnu.org/licenses/.
 * 
 * $Rev$
 * Last modified by $Author$
 * $Date$
 */

package tigase.util;

/**
 * Created: Sep 8, 2009 7:32:09 PM
 *
 * @author <a href="mailto:artur.hefczyc@tigase.org">Artur Hefczyc</a>
 * @version $Rev$
 */
public class FloatHistoryCache {

	private float[] buffer = null;
	private int start = 0;
	private int count = 0;

	public FloatHistoryCache(int limit) {
		buffer = new float[limit];
	}

	public synchronized void addItem(float item) {
		int ix = (start + count) % buffer.length;
		buffer[ix] = item;
		if (count < buffer.length) {
			count++;
		} else {
			start++;
			start %= buffer.length;
		}
	}

	public synchronized float[] getCurrentHistory() {
		float[] result = new float[count];
		for (int i = 0; i < count; i++) {
			int ix = (start + i) % buffer.length;
			result[i] = buffer[ix];
		}
		return result;
	}

}