/*
* Copyright (c) 1998-2010 Caucho Technology -- all rights reserved
*
* This file is part of Resin(R) Open Source
*
* Each copy or derived work must preserve the copyright notice and this
* notice unmodified.
*
* Resin Open Source is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* Resin Open Source 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, or any warranty
* of NON-INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with Resin Open Source; if not, write to the
*
* Free Software Foundation, Inc.
* 59 Temple Place, Suite 330
* Boston, MA 02111-1307 USA
*
* @author Scott Ferguson
*/
package com.caucho.env.meter;
import java.util.concurrent.atomic.AtomicLong;
public final class CountMeter extends AbstractMeter {
// sample data
private final AtomicLong _totalCount = new AtomicLong();
private long _lastTotal;
public CountMeter(String name)
{
super(name);
}
public final void start()
{
_totalCount.incrementAndGet();
}
/**
* Sample the total count
*/
public final double sample()
{
long totalCount = _totalCount.get();
long lastTotal = _lastTotal;
_lastTotal = totalCount;
return totalCount - lastTotal;
}
}