src/main/java/org/apache/log4j/RollingFileAppender.java - logging-log4j1 - Git at Google

 /*
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.
  * The ASF licenses this file to You under the Apache License, Version 2.0
  * (the "License"); you may not use this file except in compliance with
  * the License.  You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */


 package org.apache.log4j;

 import java.io.IOException;
 import java.io.Writer;
 import java.io.File;
 import java.io.InterruptedIOException;

 import org.apache.log4j.helpers.OptionConverter;
 import org.apache.log4j.helpers.LogLog;
 import org.apache.log4j.helpers.CountingQuietWriter;
 import org.apache.log4j.spi.LoggingEvent;

 /**
    RollingFileAppender extends FileAppender to backup the log files when
    they reach a certain size.

    @author Heinz Richter
    @author Ceki G&uuml;lc&uuml;

 */
 public class RollingFileAppender extends FileAppender {

   /**
      The default maximum file size is 10MB.
   */
   protected long maxFileSize = 10*1024*1024;

   /**
      There is one backup file by default.
    */
   protected int  maxBackupIndex  = 1;

   private long nextRollover = 0;

   /**
      The default constructor simply calls its {@link
      FileAppender#FileAppender parents constructor}.  */
   public
   RollingFileAppender() {
     super();
   }

   /**
     Instantiate a RollingFileAppender and open the file designated by
     <code>filename</code>. The opened filename will become the ouput
     destination for this appender.

     <p>If the <code>append</code> parameter is true, the file will be
     appended to. Otherwise, the file desginated by
     <code>filename</code> will be truncated before being opened.
   */
   public
   RollingFileAppender(Layout layout, String filename, boolean append)
                                       throws IOException {
     super(layout, filename, append);
   }

   /**
      Instantiate a FileAppender and open the file designated by
     <code>filename</code>. The opened filename will become the output
     destination for this appender.

     <p>The file will be appended to.  */
   public
   RollingFileAppender(Layout layout, String filename) throws IOException {
     super(layout, filename);
   }

   /**
      Returns the value of the <b>MaxBackupIndex</b> option.
    */
   public
   int getMaxBackupIndex() {
     return maxBackupIndex;
   }

  /**
     Get the maximum size that the output file is allowed to reach
     before being rolled over to backup files.

     @since 1.1
  */
   public
   long getMaximumFileSize() {
     return maxFileSize;
   }

   /**
      Implements the usual roll over behaviour.

      <p>If <code>MaxBackupIndex</code> is positive, then files
      {<code>File.1</code>, ..., <code>File.MaxBackupIndex -1</code>}
      are renamed to {<code>File.2</code>, ...,
      <code>File.MaxBackupIndex</code>}. Moreover, <code>File</code> is
      renamed <code>File.1</code> and closed. A new <code>File</code> is
      created to receive further log output.

      <p>If <code>MaxBackupIndex</code> is equal to zero, then the
      <code>File</code> is truncated with no backup files created.

    */
   public // synchronization not necessary since doAppend is alreasy synched
   void rollOver() {
     File target;
     File file;

     if (qw != null) {
         long size = ((CountingQuietWriter) qw).getCount();
         LogLog.debug("rolling over count=" + size);
         //   if operation fails, do not roll again until
         //      maxFileSize more bytes are written
         nextRollover = size + maxFileSize;
     }
     LogLog.debug("maxBackupIndex="+maxBackupIndex);

     boolean renameSucceeded = true;
     // If maxBackups <= 0, then there is no file renaming to be done.
     if(maxBackupIndex > 0) {
       // Delete the oldest file, to keep Windows happy.
       file = new File(fileName + '.' + maxBackupIndex);
       if (file.exists())
        renameSucceeded = file.delete();

       // Map {(maxBackupIndex - 1), ..., 2, 1} to {maxBackupIndex, ..., 3, 2}
       for (int i = maxBackupIndex - 1; i >= 1 && renameSucceeded; i--) {
 	file = new File(fileName + "." + i);
 	if (file.exists()) {
 	  target = new File(fileName + '.' + (i + 1));
 	  LogLog.debug("Renaming file " + file + " to " + target);
 	  renameSucceeded = file.renameTo(target);
 	}
       }

     if(renameSucceeded) {
       // Rename fileName to fileName.1
       target = new File(fileName + "." + 1);

       this.closeFile(); // keep windows happy.

       file = new File(fileName);
       LogLog.debug("Renaming file " + file + " to " + target);
       renameSucceeded = file.renameTo(target);
       //
       //   if file rename failed, reopen file with append = true
       //
       if (!renameSucceeded) {
           try {
             this.setFile(fileName, true, bufferedIO, bufferSize);
           }
           catch(IOException e) {
               if (e instanceof InterruptedIOException) {
                   Thread.currentThread().interrupt();
               }
               LogLog.error("setFile("+fileName+", true) call failed.", e);
           }
       }
     }
     }

     //
     //   if all renames were successful, then
     //
     if (renameSucceeded) {
     try {
       // This will also close the file. This is OK since multiple
       // close operations are safe.
       this.setFile(fileName, false, bufferedIO, bufferSize);
       nextRollover = 0;
     }
     catch(IOException e) {
         if (e instanceof InterruptedIOException) {
             Thread.currentThread().interrupt();
         }
         LogLog.error("setFile("+fileName+", false) call failed.", e);
     }
     }
   }

   public
   synchronized
   void setFile(String fileName, boolean append, boolean bufferedIO, int bufferSize)
                                                                  throws IOException {
     super.setFile(fileName, append, this.bufferedIO, this.bufferSize);
     if(append) {
       File f = new File(fileName);
       ((CountingQuietWriter) qw).setCount(f.length());
     }
   }


   /**
      Set the maximum number of backup files to keep around.

      <p>The <b>MaxBackupIndex</b> option determines how many backup
      files are kept before the oldest is erased. This option takes
      a positive integer value. If set to zero, then there will be no
      backup files and the log file will be truncated when it reaches
      <code>MaxFileSize</code>.
    */
   public
   void setMaxBackupIndex(int maxBackups) {
     this.maxBackupIndex = maxBackups;
   }

   /**
      Set the maximum size that the output file is allowed to reach
      before being rolled over to backup files.

      <p>This method is equivalent to {@link #setMaxFileSize} except
      that it is required for differentiating the setter taking a
      <code>long</code> argument from the setter taking a
      <code>String</code> argument by the JavaBeans {@link
      java.beans.Introspector Introspector}.

      @see #setMaxFileSize(String)
  */
   public
   void setMaximumFileSize(long maxFileSize) {
     this.maxFileSize = maxFileSize;
   }


   /**
      Set the maximum size that the output file is allowed to reach
      before being rolled over to backup files.

      <p>In configuration files, the <b>MaxFileSize</b> option takes an
      long integer in the range 0 - 2^63. You can specify the value
      with the suffixes "KB", "MB" or "GB" so that the integer is
      interpreted being expressed respectively in kilobytes, megabytes
      or gigabytes. For example, the value "10KB" will be interpreted
      as 10240.
    */
   public
   void setMaxFileSize(String value) {
     maxFileSize = OptionConverter.toFileSize(value, maxFileSize + 1);
   }

   protected
   void setQWForFiles(Writer writer) {
      this.qw = new CountingQuietWriter(writer, errorHandler);
   }

   /**
      This method differentiates RollingFileAppender from its super
      class.

      @since 0.9.0
   */
   protected
   void subAppend(LoggingEvent event) {
     super.subAppend(event);
     if(fileName != null && qw != null) {
         long size = ((CountingQuietWriter) qw).getCount();
         if (size >= maxFileSize && size >= nextRollover) {
             rollOver();
         }
     }
    }
 }
	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You under the Apache License, Version 2.0
	* (the "License"); you may not use this file except in compliance with
	* the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/



	package org.apache.log4j;

	import java.io.IOException;
	import java.io.Writer;
	import java.io.File;
	import java.io.InterruptedIOException;

	import org.apache.log4j.helpers.OptionConverter;
	import org.apache.log4j.helpers.LogLog;
	import org.apache.log4j.helpers.CountingQuietWriter;
	import org.apache.log4j.spi.LoggingEvent;

	/**
	RollingFileAppender extends FileAppender to backup the log files when
	they reach a certain size.

	@author Heinz Richter
	@author Ceki Gülcü

	*/
	public class RollingFileAppender extends FileAppender {

	/**
	The default maximum file size is 10MB.
	*/
	protected long maxFileSize = 1010241024;

	/**
	There is one backup file by default.
	*/
	protected int maxBackupIndex = 1;

	private long nextRollover = 0;

	/**
	The default constructor simply calls its {@link
	FileAppender#FileAppender parents constructor}. */
	public
	RollingFileAppender() {
	super();
	}

	/**
	Instantiate a RollingFileAppender and open the file designated by
	<code>filename</code>. The opened filename will become the ouput
	destination for this appender.

	<p>If the <code>append</code> parameter is true, the file will be
	appended to. Otherwise, the file desginated by
	<code>filename</code> will be truncated before being opened.
	*/
	public
	RollingFileAppender(Layout layout, String filename, boolean append)
	throws IOException {
	super(layout, filename, append);
	}

	/**
	Instantiate a FileAppender and open the file designated by
	<code>filename</code>. The opened filename will become the output
	destination for this appender.

	<p>The file will be appended to. */
	public
	RollingFileAppender(Layout layout, String filename) throws IOException {
	super(layout, filename);
	}

	/**
	Returns the value of the <b>MaxBackupIndex</b> option.
	*/
	public
	int getMaxBackupIndex() {
	return maxBackupIndex;
	}

	/**
	Get the maximum size that the output file is allowed to reach
	before being rolled over to backup files.

	@since 1.1
	*/
	public
	long getMaximumFileSize() {
	return maxFileSize;
	}

	/**
	Implements the usual roll over behaviour.

	<p>If <code>MaxBackupIndex</code> is positive, then files
	{<code>File.1</code>, ..., <code>File.MaxBackupIndex -1</code>}
	are renamed to {<code>File.2</code>, ...,
	<code>File.MaxBackupIndex</code>}. Moreover, <code>File</code> is
	renamed <code>File.1</code> and closed. A new <code>File</code> is
	created to receive further log output.

	<p>If <code>MaxBackupIndex</code> is equal to zero, then the
	<code>File</code> is truncated with no backup files created.

	*/
	public // synchronization not necessary since doAppend is alreasy synched
	void rollOver() {
	File target;
	File file;

	if (qw != null) {
	long size = ((CountingQuietWriter) qw).getCount();
	LogLog.debug("rolling over count=" + size);
	// if operation fails, do not roll again until
	// maxFileSize more bytes are written
	nextRollover = size + maxFileSize;
	}
	LogLog.debug("maxBackupIndex="+maxBackupIndex);

	boolean renameSucceeded = true;
	// If maxBackups <= 0, then there is no file renaming to be done.
	if(maxBackupIndex > 0) {
	// Delete the oldest file, to keep Windows happy.
	file = new File(fileName + '.' + maxBackupIndex);
	if (file.exists())
	renameSucceeded = file.delete();

	// Map {(maxBackupIndex - 1), ..., 2, 1} to {maxBackupIndex, ..., 3, 2}
	for (int i = maxBackupIndex - 1; i >= 1 && renameSucceeded; i--) {
	file = new File(fileName + "." + i);
	if (file.exists()) {
	target = new File(fileName + '.' + (i + 1));
	LogLog.debug("Renaming file " + file + " to " + target);
	renameSucceeded = file.renameTo(target);
	}
	}

	if(renameSucceeded) {
	// Rename fileName to fileName.1
	target = new File(fileName + "." + 1);

	this.closeFile(); // keep windows happy.

	file = new File(fileName);
	LogLog.debug("Renaming file " + file + " to " + target);
	renameSucceeded = file.renameTo(target);
	//
	// if file rename failed, reopen file with append = true
	//
	if (!renameSucceeded) {
	try {
	this.setFile(fileName, true, bufferedIO, bufferSize);
	}
	catch(IOException e) {
	if (e instanceof InterruptedIOException) {
	Thread.currentThread().interrupt();
	}
	LogLog.error("setFile("+fileName+", true) call failed.", e);
	}
	}
	}
	}

	//
	// if all renames were successful, then
	//
	if (renameSucceeded) {
	try {
	// This will also close the file. This is OK since multiple
	// close operations are safe.
	this.setFile(fileName, false, bufferedIO, bufferSize);
	nextRollover = 0;
	}
	catch(IOException e) {
	if (e instanceof InterruptedIOException) {
	Thread.currentThread().interrupt();
	}
	LogLog.error("setFile("+fileName+", false) call failed.", e);
	}
	}
	}

	public
	synchronized
	void setFile(String fileName, boolean append, boolean bufferedIO, int bufferSize)
	throws IOException {
	super.setFile(fileName, append, this.bufferedIO, this.bufferSize);
	if(append) {
	File f = new File(fileName);
	((CountingQuietWriter) qw).setCount(f.length());
	}
	}


	/**
	Set the maximum number of backup files to keep around.

	<p>The <b>MaxBackupIndex</b> option determines how many backup
	files are kept before the oldest is erased. This option takes
	a positive integer value. If set to zero, then there will be no
	backup files and the log file will be truncated when it reaches
	<code>MaxFileSize</code>.
	*/
	public
	void setMaxBackupIndex(int maxBackups) {
	this.maxBackupIndex = maxBackups;
	}

	/**
	Set the maximum size that the output file is allowed to reach
	before being rolled over to backup files.

	<p>This method is equivalent to {@link #setMaxFileSize} except
	that it is required for differentiating the setter taking a
	<code>long</code> argument from the setter taking a
	<code>String</code> argument by the JavaBeans {@link
	java.beans.Introspector Introspector}.

	@see #setMaxFileSize(String)
	*/
	public
	void setMaximumFileSize(long maxFileSize) {
	this.maxFileSize = maxFileSize;
	}


	/**
	Set the maximum size that the output file is allowed to reach
	before being rolled over to backup files.

	<p>In configuration files, the <b>MaxFileSize</b> option takes an
	long integer in the range 0 - 2^63. You can specify the value
	with the suffixes "KB", "MB" or "GB" so that the integer is
	interpreted being expressed respectively in kilobytes, megabytes
	or gigabytes. For example, the value "10KB" will be interpreted
	as 10240.
	*/
	public
	void setMaxFileSize(String value) {
	maxFileSize = OptionConverter.toFileSize(value, maxFileSize + 1);
	}

	protected
	void setQWForFiles(Writer writer) {
	this.qw = new CountingQuietWriter(writer, errorHandler);
	}

	/**
	This method differentiates RollingFileAppender from its super
	class.

	@since 0.9.0
	*/
	protected
	void subAppend(LoggingEvent event) {
	super.subAppend(event);
	if(fileName != null && qw != null) {
	long size = ((CountingQuietWriter) qw).getCount();
	if (size >= maxFileSize && size >= nextRollover) {
	rollOver();
	}
	}
	}
	}