001/*
002 * (C) Copyright 2006-2008 Nuxeo SAS (http://nuxeo.com/) and contributors.
003 *
004 * All rights reserved. This program and the accompanying materials
005 * are made available under the terms of the GNU Lesser General Public License
006 * (LGPL) version 2.1 which accompanies this distribution, and is available at
007 * http://www.gnu.org/licenses/lgpl.html
008 *
009 * This library is distributed in the hope that it will be useful,
010 * but WITHOUT ANY WARRANTY; without even the implied warranty of
011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
012 * Lesser General Public License for more details.
013 *
014 * Contributors:
015 *     Nuxeo - initial API and implementation
016 *
017 * $Id$
018 */
019
020package org.nuxeo.ecm.platform.importer.log;
021
022import java.util.LinkedList;
023import java.util.concurrent.locks.ReentrantReadWriteLock;
024
025import org.apache.commons.logging.Log;
026
027/**
028 * @author Thierry Delprat
029 */
030public class BufferredLogger extends BasicLogger {
031
032    protected ReentrantReadWriteLock lock = new ReentrantReadWriteLock();
033
034    protected static int DEFAULT_LOG_BUFFER_LENGTH = 50;
035
036    protected Integer bufferSize = null;
037
038    protected LinkedList<String> logStack = new LinkedList<String>();
039
040    public BufferredLogger(Log javaLogger) {
041        super(javaLogger);
042    }
043
044    public BufferredLogger(Log javaLogger, int bufferSize) {
045        super(javaLogger);
046        this.bufferSize = bufferSize;
047    }
048
049    protected int getMaxStackLen() {
050        if (bufferSize == null) {
051            bufferSize = DEFAULT_LOG_BUFFER_LENGTH;
052        }
053        return bufferSize;
054    }
055
056    protected void logInStack(String level, String message) {
057        if (!bufferActive) {
058            return;
059        }
060        lock.writeLock().lock();
061        try {
062            logStack.add(level + " : " + message);
063            if (logStack.size() > getMaxStackLen()) {
064                logStack.remove();
065            }
066        } finally {
067            lock.writeLock().unlock();
068        }
069    }
070
071    @Override
072    public String getLoggerBuffer(String sep) {
073        StringBuffer sb = new StringBuffer();
074
075        lock.readLock().lock();
076        try {
077            for (String line : logStack) {
078                sb.append(line);
079                sb.append(sep);
080            }
081            return sb.toString();
082        } finally {
083            lock.readLock().unlock();
084        }
085    }
086
087    @Override
088    public void info(String message) {
089        super.info(message);
090        if (bufferActive) {
091            logInStack("INFO", message);
092        }
093    }
094
095    @Override
096    public void warn(String message) {
097        super.warn(message);
098        if (bufferActive) {
099            logInStack("WARN", message);
100        }
101    }
102
103    @Override
104    public void debug(String message) {
105        super.debug(message);
106        if (bufferActive) {
107            logInStack("DEBUG", message);
108        }
109    }
110
111    @Override
112    public void debug(String message, Throwable t) {
113        super.debug(message, t);
114        if (bufferActive) {
115            logInStack("DEBUG", message);
116            logInStack("=>ERR", t.getClass().getSimpleName() + ":" + t.getMessage());
117        }
118    }
119
120    @Override
121    public void error(String message) {
122        super.error(message);
123        if (bufferActive) {
124            logInStack("ERROR", message);
125        }
126    }
127
128    @Override
129    public void error(String message, Throwable t) {
130        super.error(message, t);
131        if (bufferActive) {
132            logInStack("ERROR", message);
133            logInStack("=>ERR", t.getClass().getSimpleName() + ":" + t.getMessage());
134        }
135    }
136
137}