001/**
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.activemq.usage;
018
019import java.io.File;
020
021import org.apache.activemq.store.PersistenceAdapter;
022import org.apache.activemq.util.StoreUtil;
023
024/**
025 * Used to keep track of how much of something is being used so that a
026 * productive working set usage can be controlled. Main use case is manage
027 * memory usage.
028 *
029 * @org.apache.xbean.XBean
030 *
031 */
032public class StoreUsage extends PercentLimitUsage<StoreUsage> {
033
034    private PersistenceAdapter store;
035
036    public StoreUsage() {
037        super(null, null, 1.0f);
038    }
039
040    public StoreUsage(String name, PersistenceAdapter store) {
041        super(null, name, 1.0f);
042        this.store = store;
043        updateLimitBasedOnPercent();
044    }
045
046    public StoreUsage(StoreUsage parent, String name) {
047        super(parent, name, 1.0f);
048        this.store = parent.store;
049        updateLimitBasedOnPercent();
050    }
051
052    @Override
053    protected long retrieveUsage() {
054        if (store == null)
055            return 0;
056        return store.size();
057    }
058
059    public PersistenceAdapter getStore() {
060        return store;
061    }
062
063    public void setStore(PersistenceAdapter store) {
064        this.store = store;
065        if (percentLimit > 0 && store != null) {
066            //will trigger onLimitChange
067            updateLimitBasedOnPercent();
068        } else {
069            onLimitChange();
070        }
071    }
072
073    @Override
074    public int getPercentUsage() {
075        usageLock.writeLock().lock();
076        try {
077            percentUsage = caclPercentUsage();
078            return super.getPercentUsage();
079        } finally {
080            usageLock.writeLock().unlock();
081        }
082    }
083
084    @Override
085    public boolean waitForSpace(long timeout, int highWaterMark) throws InterruptedException {
086        if (parent != null) {
087            if (parent.waitForSpace(timeout, highWaterMark)) {
088                return true;
089            }
090        }
091
092        return super.waitForSpace(timeout, highWaterMark);
093    }
094
095    @Override
096    protected void updateLimitBasedOnPercent() {
097        usageLock.writeLock().lock();
098        try {
099
100            if (percentLimit > 0 && store != null) {
101                File dir = StoreUtil.findParentDirectory(store.getDirectory());
102
103                if (dir != null) {
104                    this.setLimit(dir.getTotalSpace() * percentLimit / 100);
105                }
106            }
107        } finally {
108            usageLock.writeLock().unlock();
109        }
110    }
111}