// $Header: /home/cvs/jakarta-jmeter/src/core/org/apache/jmeter/engine/LagDetector.java,v 1.5 2004/02/13 02:21:37 sebb Exp $
/*
 * Copyright 2001-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache 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.apache.org/licenses/LICENSE-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.apache.jmeter.engine;

/**
 * TODO - appears to be unused
 * 
 * @version $Revision: 1.5 $
 */
public class LagDetector extends Thread
{
    private long incr = MAX_SLEEP / DIV;
    private long totalLag;
    private int count;
    private boolean running;
    public final static long MAX_SLEEP = 500;

    private final static long DIV = 3;

    /**
     * Constructor for the LagDetector object.
     */
    public LagDetector()
    {
    }

    /**
     * Gets the AveLag attribute of the LagDetector object.
     *
     * @return    the AveLag value
     */
    public float getAveLag()
    {
        return (float) ((float) totalLag / (float) count);
    }

    /**
     * Gets the LagRatio attribute of the LagDetector object.
     *
     * @return    the LagRatio value
     */
    public float getLagRatio()
    {
        return ((float) totalLag / (float) count) / incr;
    }

    public void stopRunning()
    {
        running = false;
    }

    /**
     * Main processing method for the LagDetector object.
     */
    public void run()
    {
        running = true;
        long time;
        totalLag = 0;
        count = 0;
        while (running)
        {
            time = System.currentTimeMillis();
            try
            {
                Thread.sleep(incr);
            }
            catch (Exception e)
            {
            }
            time = System.currentTimeMillis() - time;
            totalLag += time - incr;
            count++;
        }
    }
}