logger.java

pastry的java实现的2.0b版

/*************************************************************************

"FreePastry" Peer-to-Peer Application Development Substrate 

Copyright 2002, Rice University. All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:

- Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.

- 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.

- Neither  the name  of Rice  University (RICE) nor  the names  of its
contributors may be  used to endorse or promote  products derived from
this software without specific prior written permission.

This software is provided by RICE and the contributors on an "as is"
basis, without any representations or warranties of any kind, express
or implied including, but not limited to, representations or
warranties of non-infringement, merchantability or fitness for a
particular purpose. In no event shall RICE or 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.

********************************************************************************/
/*
 *  Created on Apr 6, 2005
 */
package rice.environment.logging;

/**
 * The Logger is a simplified interface of the java.util.logging.Logger. It is
 * envisioned that one could implement this interface using java.util.logging,
 * but that many times this interface is overkill.
 *
 * @version $Id: pretty.settings 2305 2005-03-11 20:22:33Z jeffh $
 * @author Jeff Hoye
 */
public abstract class Logger {

  /**
   * This is public for performance reasons.
   */
  public int level = 0;

  // These are suggested base level priorities.

  /**
   * SEVERE is a message level indicating a serious failure.
   */
  public final static int SEVERE = 1000;

  /**
   * WARNING is a message level indicating a potential problem.
   */
  public final static int WARNING = 900;

  /**
   * INFO is a message level for informational messages. Things that only happen
   * once per node creation.
   */
  public final static int INFO = 800;

  /**
   * CONFIG is a message level for static configuration messages.
   */
  public final static int CONFIG = 700;

  /**
   * FINE is a message level providing tracing information. Things that get
   * logged once per specific message.
   */
  public final static int FINE = 500;

  /**
   * FINER indicates a fairly detailed tracing message. Things that get logged
   * once per general message.
   */
  public final static int FINER = 400;

  /**
   * FINEST indicates a highly detailed tracing message. Things that happen more
   * than once per general message.
   */
  public final static int FINEST = 300;

  /**
   * ALL indicates that all messages should be logged.
   */
  public final static int ALL = Integer.MIN_VALUE;

  /**
   * OFF is a special level that can be used to turn off logging.
   */
  public final static int OFF = Integer.MAX_VALUE;

  /**
   * Prints the message if the priority is equal to or higher than the minimum
   * priority.
   *
   * @param message the message to print
   */
  public abstract void log(String message);

  /**
   * Prints the stack trace of the exception. If you only want to print the
   * exception's string, use the log() method. This is necessary because
   * Exception doesn't have a convienient way of printing the stack trace as a
   * string.
   *
   * @param exception the exception to print
   * @param message DESCRIBE THE PARAMETER
   */
  public abstract void logException(String message, Throwable exception);
}