/*
    * $Id: LoggerHandler.java 124 2004-11-01 18:09:40Z josem $
    *
    * Tarsis
    * Copyright (C) 2002 Talika Open Source Group
    *
    * This program is free software; you can redistribute it and/or modify
    * it under the terms of the GNU General Public License as published by
    * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   *
   */
  
  package org.talika.tarsis.log;
  
  
  import java.util.Collection;
  import java.util.LinkedList;
  import java.util.Iterator;
  import java.util.List;
  
  import org.talika.tarsis.context.Context;
  import org.talika.tarsis.service.ServiceException;
  
  /**
   * Special implementation of <code>Logger</code> interface that serves as a multiplexer
   * that writes log messages to a list of <code>Logger</code> instances.
   *
   * @author  Jose M. Palomar
   * @version $Revision: 124 $
   */
  public final class LoggerHandler extends LoggerService {
  
      // Constants
  
      // Fields
      /**
       * Default <code>Logger</code>.
       */
      private ConsoleLogger defaultLogger = new ConsoleLogger();
  
      /**
       * List of <code>Logger</code> instances.
       */
      private List loggers = new LinkedList();
  
      // Constructors
      /**
       * Creates a new <code>LoggerHandler</code>.
       */
      public LoggerHandler() {
          defaultLogger.setLogLevel(Logger.DEBUG);
      }
  
      // Methods
      // Life-cycle
      /**
       * Called by the framework to indicate that is being placed into service.<br>
       * <br>
       * Initializes the list of <code>Logger</code> instances.
       *
       * @param context Context context that initialized service.
       * @throws ServiceException if an exception has occurred that interferes with the
       * services's normal operation
       * @see org.talika.tarsis.service.Service#init(Context)
       */
      public void init(Context context) throws ServiceException {
          super.init(context);
  
          Iterator loggersIterator = loggers.iterator();
          while (loggersIterator.hasNext()) {
              LoggerService logger = (LoggerService) loggersIterator.next();
              logger.init(context);
          }
  
      }
  
      /**
       * Called by the framework to indicate that is being placed out of service.<br>
       * <br>
       * Destroys the list of <code>Logger</code> instances.
       *
       * @see org.talika.tarsis.service.Service#destroy()
       */
      public void destroy() {
  
          Iterator loggersIterator = loggers.iterator();
          while (loggersIterator.hasNext()) {
              LoggerService logger = (LoggerService) loggersIterator.next();
              logger.destroy();
         }
 
         loggers.clear();
 
         super.destroy();
     }
 
     /**
      * Returns name of service.
      *
      * @return String name of service.
      * @see org.talika.tarsis.service.Service#getName()
      */
     public String getName() {
         return "LoggerHandler";
     }
 
     // Handler
     /**
      * Adds a <code>Logger</code> instance to <code>Logger</code> list.
      *
      * @param logger LoggerService a <code>Logger</code> instance.
      */
     public void addLogger(LoggerService logger) {
         loggers.add(logger);
     }
 
     /**
      * Adds a <code>Collection</code> of <code>Logger</code> instances to
      * <code>Logger</code> list.
      *
      * @param loggers Collection a <code>Collection</code> of <code>Logger</code>
      * instances.
      */
     public void addLoggers(Collection loggers) {
         this.loggers.addAll(loggers);
     }
 
     // Logger
     /**
      * Returns log level parameter.
      *
      * @return int log level parameter.
      * @see org.talika.tarsis.log.Logger#getLogLevel()
      */
     public int getLogLevel() {
         return defaultLogger.getLogLevel();
     }
 
     /**
      * Sets log level parameter.
      *
      * @param logLevel int log level parameter.
      */
     public void setLogLevel(int logLevel) {
         defaultLogger.setLogLevel(logLevel);
     }
 
     /**
      * Log a message using given level.
      *
      * @param level int log level.
      * @param msg String message.
      * @see org.talika.tarsis.log.Logger#log(int, String)
      */
     public void log(int level, String msg) {
 
         defaultLogger.log(level, msg);
 
         Iterator loggersIterator = loggers.iterator();
         while (loggersIterator.hasNext()) {
             LoggerService logger = (LoggerService) loggersIterator.next();
             if (level >= logger.getLogLevel()) {
                 logger.log(level, msg);
             }
         }
 
     }
 
     /**
      * Log an error message using given level.
      *
      * @param level int log level.
      * @param msg String message.
      * @param t Throwable a <code>Throwable</code> object.
      * @see org.talika.tarsis.log.Logger#log(int, String, Throwable)
      */
     public void log(int level, String msg, Throwable t) {
 
         defaultLogger.log(level, msg, t);
 
         Iterator loggersIterator = loggers.iterator();
         while (loggersIterator.hasNext()) {
             LoggerService logger = (LoggerService) loggersIterator.next();
             if (level >= logger.getLogLevel()) {
                 logger.log(level, msg, t);
             }
         }
 
     }
 
     /**
      * Writes a message to log.
      *
      * @param level int log level.
      * @param msg String message.
      */
     protected void writeLog(int level, String msg) {
 
         defaultLogger.writeLog(level, msg);
 
         Iterator loggersIterator = loggers.iterator();
         while (loggersIterator.hasNext()) {
             LoggerService logger = (LoggerService) loggersIterator.next();
             logger.writeLog(level, msg);
         }
 
     }
 
     /**
      * Writes an error message to log.
      *
      * @param level int log level.
      * @param msg String message.
      * @param t Throwable a <code>Throwable</code> object.
      */
     protected void writeLog(int level, String msg, Throwable t) {
 
         defaultLogger.writeLog(level, msg, t);
 
         Iterator loggersIterator = loggers.iterator();
         while (loggersIterator.hasNext()) {
             LoggerService logger = (LoggerService) loggersIterator.next();
             logger.writeLog(level, msg, t);
         }
 
     }
 
 }