1/**
2 * Copyright (c) 2004-2011 QOS.ch
3 * All rights reserved.
4 *
5 * Permission is hereby granted, free  of charge, to any person obtaining
6 * a  copy  of this  software  and  associated  documentation files  (the
7 * "Software"), to  deal in  the Software without  restriction, including
8 * without limitation  the rights to  use, copy, modify,  merge, publish,
9 * distribute,  sublicense, and/or sell  copies of  the Software,  and to
10 * permit persons to whom the Software  is furnished to do so, subject to
11 * the following conditions:
12 *
13 * The  above  copyright  notice  and  this permission  notice  shall  be
14 * included in all copies or substantial portions of the Software.
15 *
16 * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
17 * EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
18 * MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
19 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
20 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
21 * OF CONTRACT, TORT OR OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION
22 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23 *
24 */
25package org.slf4j.impl;
26
27import java.util.concurrent.ConcurrentHashMap;
28import java.util.concurrent.ConcurrentMap;
29
30import org.apache.log4j.LogManager;
31import org.slf4j.ILoggerFactory;
32import org.slf4j.Logger;
33
34/**
35 * Log4jLoggerFactory is an implementation of {@link ILoggerFactory} returning
36 * the appropriate named {@link Log4jLoggerAdapter} instance.
37 *
38 * @author Ceki Gülcü
39 */
40public class Log4jLoggerFactory implements ILoggerFactory {
41
42    // key: name (String), value: a Log4jLoggerAdapter;
43    ConcurrentMap<String, Logger> loggerMap;
44
45    public Log4jLoggerFactory() {
46        loggerMap = new ConcurrentHashMap<String, Logger>();
47    }
48
49    /*
50     * (non-Javadoc)
51     *
52     * @see org.slf4j.ILoggerFactory#getLogger(java.lang.String)
53     */
54    public Logger getLogger(String name) {
55        Logger slf4jLogger = loggerMap.get(name);
56        if (slf4jLogger != null) {
57            return slf4jLogger;
58        } else {
59            org.apache.log4j.Logger log4jLogger;
60            if (name.equalsIgnoreCase(Logger.ROOT_LOGGER_NAME))
61                log4jLogger = LogManager.getRootLogger();
62            else
63                log4jLogger = LogManager.getLogger(name);
64
65            Logger newInstance = new Log4jLoggerAdapter(log4jLogger);
66            Logger oldInstance = loggerMap.putIfAbsent(name, newInstance);
67            return oldInstance == null ? newInstance : oldInstance;
68        }
69    }
70}
71