rotatinglogmanager.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 Jun 28, 2005
 *
 */
package rice.environment.logging.file;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.PrintStream;
import java.text.*;
import java.util.Date;

import javax.swing.text.DateFormatter;

import rice.environment.Environment;
import rice.environment.logging.AbstractLogManager;
import rice.environment.logging.LogManager;
import rice.environment.logging.Logger;
import rice.environment.logging.simple.SimpleLogManager;
import rice.environment.logging.simple.SimpleLogger;
import rice.environment.params.Parameters;
import rice.environment.time.TimeSource;
import rice.p2p.commonapi.CancellableTask;
import rice.selector.SelectorManager;
import rice.selector.TimerTask;

/**
 * @version $Id: pretty.settings 2305 2005-03-11 20:22:33Z jeffh $
 * @author jstewart
 */
public class RotatingLogManager extends AbstractLogManager {

  /**
   * DESCRIBE THE FIELD
   */
  protected TimerTask rotateTask;
  /**
   * DESCRIBE THE FIELD
   */
  protected TimerTask sizeRotateTask;

  /**
   * Constructor for RotatingLogManager.
   *
   * @param timeSource DESCRIBE THE PARAMETER
   * @param params DESCRIBE THE PARAMETER
   */
  public RotatingLogManager(TimeSource timeSource, Parameters params) {
    this(timeSource, params, "", null);
  }

  /**
   * @param timeSource
   * @param params
   * @param prefix
   * @param dateFormat DESCRIBE THE PARAMETER
   */
  public RotatingLogManager(TimeSource timeSource, Parameters params,
                            String prefix, String dateFormat) {
    super(AbstractLogManager.nullPrintStream, timeSource, params, prefix, dateFormat);
    rotate();
  }

  /**
   * DESCRIBE THE METHOD
   *
   * @param sm DESCRIBE THE PARAMETER
   */
  public void startRotateTask(SelectorManager sm) {
    if (rotateTask == null) {
      rotateTask = new LogRotationTask();
      sm.getTimer().schedule(rotateTask, params.getInt("log_rotate_interval"),
        params.getInt("log_rotate_interval"));
      if (params.contains("log_rotate_size_check_interval") && sizeRotateTask == null) {
        sizeRotateTask = new LogSizeRotationTask();
        sm.getTimer().schedule(sizeRotateTask,
          params.getInt("log_rotate_size_check_interval"),
          params.getInt("log_rotate_size_check_interval"));
      }
    } else {
      throw new RuntimeException("Task already started");
    }
  }

  /**
   * DESCRIBE THE METHOD
   */
  public void cancelRotateTask() {
    rotateTask.cancel();
    rotateTask = null;
  }

  /**
   * DESCRIBE THE METHOD
   */
  void rotate() {
    synchronized (this) {
      PrintStream oldps = ps;
      String dateFormat = params.getString("log_rotating_date_format");
      DateFormatter dateFormatter = null;
      if (dateFormat != null && !dateFormat.equals("")) {
        dateFormatter = new DateFormatter(new SimpleDateFormat(
          dateFormat));
      }

      String filename = params.getString("log_rotate_filename");
      File oldfile = new File(filename);
      if (oldfile.exists()) {
        long filedate = oldfile.lastModified();
        String rot_filename = filename + "." + filedate;
        if (dateFormatter != null) {
          try {
            rot_filename = filename + "." + dateFormatter.valueToString(new Date(filedate));
          } catch (ParseException pe) {
            pe.printStackTrace();
          }
        }
        oldfile.renameTo(new File(rot_filename));
      }
      try {
        ps = new PrintStream(new FileOutputStream(oldfile, true), true);
        if (oldps != null) {
          oldps.close();
        }
      } catch (FileNotFoundException e) {
        if (ps != oldps) {
          ps = oldps;
        }
        System.err.println("could not rotate log " + filename + " because of "
          + e);
        // XXX should also log it
      }
    }
  }

  /**
   * DESCRIBE THE METHOD
   *
   * @param clazz DESCRIBE THE PARAMETER
   * @param level DESCRIBE THE PARAMETER
   * @param useDefault DESCRIBE THE PARAMETER
   * @return DESCRIBE THE RETURN VALUE
   */
  protected Logger constructLogger(String clazz, int level, boolean useDefault) {
    return new SimpleLogger(clazz, this, level, useDefault);
  }

  /**
   * DESCRIBE THE CLASS
   *
   * @version $Id: pretty.settings 2305 2005-03-11 20:22:33Z jeffh $
   * @author jeffh
   */
  private class LogRotationTask extends TimerTask {
    /**
     * Main processing method for the LogRotationTask object
     */
    public void run() {
      rotate();
    }
  }

  /**
   * DESCRIBE THE CLASS
   *
   * @version $Id: pretty.settings 2305 2005-03-11 20:22:33Z jeffh $
   * @author jeffh
   */
  private class LogSizeRotationTask extends TimerTask {
    /**
     * Main processing method for the LogSizeRotationTask object
     */
    public void run() {
      synchronized (RotatingLogManager.this) {
        if (new File(params.getString("log_rotate_filename")).length() >= params.getLong("log_rotate_max_size")) {
          rotate();
        }
      }
    }
  }
}