logger.java

这是一个用java和xml编写的流媒体服务器管理软件

/*
 * ====================================================================
 * The Vovida Software License, Version 1.0
 *
 * Copyright (c) 2000 Vovida Networks, Inc.  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 names "VOCAL", "Vovida Open Communication Application Library",
 * and "Vovida Open Communication Application Library (VOCAL)" must
 * not be used to endorse or promote products derived from this
 * software without prior written permission. For written
 * permission, please contact [e-mail].
 *
 * 4. Products derived from this software may not be called "VOCAL", nor
 * may "VOCAL" appear in their name, without prior written
 * permission of Vovida Networks, Inc.
 *
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE AND
 * NON-INFRINGEMENT ARE DISCLAIMED.  IN NO EVENT SHALL VOVIDA
 * NETWORKS, INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT DAMAGES
 * IN EXCESS OF $1,000, NOR FOR ANY 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 Vovida
 * Networks, Inc. and many individuals on behalf of Vovida Networks,
 * Inc.  For more information on Vovida Networks, Inc., please see
 * <http://www.vovida.org/>.
 *
 */


/**
 * Title:        <p>
 * Description:  <p>
 * Copyright:    Copyright (c) <p>
 * Company:      <p>
 * @author
 * @version 1.0
 */
package vocal.util;

import javax.swing.JLabel;
import javax.swing.SwingUtilities;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.StringTokenizer;
import java.io.ByteArrayOutputStream;
import java.io.PrintStream;
import java.awt.Color;

import javax.swing.border.*;

public class Logger
{

  // Identifiers for the destinations it is possible to send log messages to
  private static final int DESTINATION_STDOUT = 0;
  private static final int DESTINATION_TEXTLABEL = 1;
  private static final int DESTINATION_TEXTAREA = 2;
  private static final int DESTINATION_FILE = 3;
  private static final int MAX_DESTINATION = DESTINATION_FILE;

  // identifiers for the individual message components
  private static final int COMPONENT_MESSAGE = 0;
  private static final int COMPONENT_METHOD = 1;
  private static final int COMPONENT_TIMESTAMP = 2;
  private static final int COMPONENT_TAG = 3;
  private static final int MAX_COMPONENT = COMPONENT_TAG;

  /**
   * Array stores flags for each destination/message component combination
   * which determine whether the particular message component will be written
   * to that destination.
   */
  private static boolean[][] msgConfig =
    new boolean[MAX_DESTINATION + 1][MAX_COMPONENT + 1];

  private static final String TRACE_TAG = "---TRACE--- ";
  private static final String ERROR_TAG = "---ERROR--- ";

  private static String messageTag = TRACE_TAG;

  private static final SimpleDateFormat dateFormatter =
    new SimpleDateFormat("hh:mm:ss:SSSS");

  private static JLabel textLabel = new JLabel();



  static
  {

    // turn of logging for all message components for all destinations
    for (int i = 1; i < MAX_COMPONENT; i++)
    {
      for (int j = 0; j < MAX_DESTINATION; j++)
      {
        msgConfig[j][i] = false;
      }
    }

    // but send the message itself everywhere
    for (int i = 0; i <= MAX_DESTINATION; i++)
    {
      msgConfig[i][COMPONENT_MESSAGE] = true;
    }

    // log the method and tag to stdout
    msgConfig[DESTINATION_STDOUT][COMPONENT_METHOD] = true;
    msgConfig[DESTINATION_STDOUT][COMPONENT_TAG] = true;
  }


  private Logger() {}


  public static void setMessageConfig(int destination, int messageId,
          boolean enabled)
  {
    msgConfig[destination][messageId] = enabled;
  }

  public static void swingLog(final String msg)
  {
    Runnable newLog = new Runnable()
    {
      public void run()
      {
        log(msg);
      }

    };

    SwingUtilities.invokeLater(newLog);
  }


  public static void log(String msg)
  {
    for (int destination = 0; destination < MAX_DESTINATION; destination++)
    {
      boolean[] enabled = msgConfig[destination];
      String message = composeLogMessage(msg, enabled);

      if (!message.equals(""))
      {
        switch (destination)
        {

          case DESTINATION_STDOUT:
          {
            System.out.println(message);
          }

            break;

          case DESTINATION_TEXTLABEL:
          {
            textLabel.setText(message);
          }

            break;

          case DESTINATION_FILE: {}
            break;

          case DESTINATION_TEXTAREA: {}
            break;
        }       // end switch destination
      }         // end if there was a message
    }           // end for each destination
  }


  private static String composeLogMessage(String usrMessage,
          boolean[] componentEnabled)
  {
    String message = "";

    if (componentEnabled[COMPONENT_TIMESTAMP])
    {
      long currentTime = System.currentTimeMillis();
      String date = dateFormatter.format(new Date(currentTime));

      message = date + " - ";
    }

    if (componentEnabled[COMPONENT_TAG])
    {
      message += messageTag;
    }

    if (componentEnabled[COMPONENT_MESSAGE])
    {
      message += usrMessage;
    }

    if (componentEnabled[COMPONENT_METHOD])
    {
      message += " - " + getMethod();
    }

    return message;
  }


  private static String getMethod()
  {
    String method = "";

    try
    {
      throw new Exception("message");
    }
    catch (Exception e)
    {
      String trace = getStackTrace(e);
      StringTokenizer traceTokenizer = new StringTokenizer(trace, "\n", false);

      String token = traceTokenizer.nextToken(); // name of the exception

      token = traceTokenizer.nextToken();
      while (token.indexOf("Logger") == -1) //in 1.3, throwable and exception show up in the stack trace
      {
        token = traceTokenizer.nextToken();
      }

      while (token.indexOf("Logger") != -1)
      {
        token = traceTokenizer.nextToken();
      }

      method = token.trim();
    }

    return method;
  }


  private static String getStackTrace(Throwable ex)
  {
    ByteArrayOutputStream byteOutput = new ByteArrayOutputStream();
    PrintStream printStream = new PrintStream(byteOutput);

    ex.printStackTrace(printStream);

    return byteOutput.toString();
  }


  public static JLabel getLogLabel()
  {
    return textLabel;
  }

}