001/*
002 * (C) Copyright 2006-2009 Nuxeo SA (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 * Contributors:
017 *     Nuxeo - initial API and implementation
018 *
019 * $Id$
020 */
021package org.nuxeo.runtime.management.counters;
022
023import java.util.Map;
024import java.util.concurrent.ConcurrentHashMap;
025
026import org.javasimon.CallbackSkeleton;
027import org.javasimon.Counter;
028
029/**
030 * Listen to Simon events to store past values of the counters History is kept in memory using
031 * {@link CounterHistoryStack}
032 *
033 * @author Tiry ([email protected])
034 */
035public class CounterHistoryRecorder extends CallbackSkeleton {
036
037    protected Map<String, CounterHistoryStack> counterHistory = new ConcurrentHashMap<String, CounterHistoryStack>();
038
039    protected int historyLength = 100;
040
041    public CounterHistoryRecorder(int size) {
042        historyLength = size;
043    }
044
045    protected CounterHistoryStack getCounterHistoryStack(Counter counter) {
046        CounterHistoryStack stack = counterHistory.get(counter.getName());
047        if (stack == null) {
048            stack = new CounterHistoryStack(historyLength);
049            counterHistory.put(counter.getName(), stack);
050        }
051        return stack;
052    }
053
054    protected void storeCounter(Counter counter) {
055        getCounterHistoryStack(counter).push(new long[] { System.currentTimeMillis(), counter.getCounter() });
056    }
057
058    @Override
059    public void counterDecrease(Counter counter, long dec) {
060        storeCounter(counter);
061    }
062
063    @Override
064    public void counterSet(Counter counter, long val) {
065        storeCounter(counter);
066    }
067
068    @Override
069    public void counterIncrease(Counter counter, long inc) {
070        storeCounter(counter);
071    }
072
073    public CounterHistoryStack getCounterHistory(String counterName) {
074        return counterHistory.get(counterName);
075    }
076}