/* * Copyright (c) 2000 jPOS.org.  All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright *    notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright *    notice, this list of conditions and the following disclaimer in *    the documentation and/or other materials provided with the *    distribution. * * 3. The end-user documentation included with the redistribution, *    if any, must include the following acknowledgment: *    "This product includes software developed by the jPOS project  *    (http://www.jpos.org/)". Alternately, this acknowledgment may  *    appear in the software itself, if and wherever such third-party  *    acknowledgments normally appear. * * 4. The names "jPOS" and "jPOS.org" must not be used to endorse  *    or promote products derived from this software without prior  *    written permission. For written permission, please contact  *    license@jpos.org. * * 5. Products derived from this software may not be called "jPOS", *    nor may "jPOS" appear in their name, without prior written *    permission of the jPOS project. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.   * IN NO EVENT SHALL THE JPOS PROJECT OR ITS CONTRIBUTORS BE LIABLE FOR  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE  * POSSIBILITY OF SUCH DAMAGE. * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of the jPOS Project.  For more * information please see <http://www.jpos.org/>. */package org.jpos.util;import java.util.Iterator;import java.util.Vector;/** * Peer class Logger forwards LogEvents generated by LogSources  * to LogListeners. * <br> * This little <a href="/doc/LoggerGuide.html">tutorial</a> * give you additional information on how to extend the jPOS's * Logger subsystem. * * @author apr@cs.com.uy * @version $Id: Logger.java,v 1.20 2005/06/25 18:31:45 apr Exp $ * @see LogEvent * @see LogSource * @see LogListener * @see Loggeable * @see SimpleLogListener * @see RotateLogListener */public class Logger {    String name;    Vector listeners;    public Logger () {        super();        listeners = new Vector ();        name = "";    }    public void addListener (LogListener l) {        synchronized (listeners) {            listeners.add (l);        }    }    public void removeListener (LogListener l) {        synchronized (listeners) {            listeners.remove (l);        }    }    public void removeAllListeners () {        synchronized (listeners) {            Iterator i = listeners.iterator();            while (i.hasNext()) {                LogListener l = ((LogListener) i.next());                if (l instanceof Destroyable) {                    ((Destroyable) l).destroy ();                }            }            listeners.clear ();        }    }    public static void log (LogEvent evt) {        Logger l = null;        LogSource source = evt.getSource();        if (source != null)            l = source.getLogger();        if (l != null && l.hasListeners ()) {            synchronized (l.listeners) {                Iterator i = l.listeners.iterator();                while (i.hasNext() && evt != null)                     evt = ((LogListener) i.next()).log (evt);            }        }    }    /**     * associates this Logger with a name using NameRegistrar     * @param name name to register     * @see NameRegistrar     */    public void setName (String name) {        this.name = name;        NameRegistrar.register ("logger."+name, this);    }    /**     * destroy logger     */    public void destroy () {        NameRegistrar.unregister ("logger."+name);        removeAllListeners ();    }    /**     * @return logger instance with given name. Creates one if necessary     * @see NameRegistrar     */    public synchronized static Logger getLogger (String name) {        Logger l;        try {            l = (Logger) NameRegistrar.get ("logger."+name);        } catch (NameRegistrar.NotFoundException e) {            l = new Logger();            l.setName (name);        }        return l;    }    /**     * @return this logger's name ("" if no name was set)     */    public String getName() {        return this.name;    }    /**     * Used by heavy used methods to avoid LogEvent creation      * @return true if Logger has associated LogListsners     */    public boolean hasListeners() {        synchronized (listeners) {            return listeners.size() > 0;        }    }}