DailyRollingFileAppenderToDirectories is a log4j DailyRollingFileAppender but allows writing to different directories.

To set up
1) put log4j.jar in your classpath, and put the DailyRollingFileAppenderToDirectories class (see listing below) in your project
2) create a log4j.properties file in your classpath with the following field set:
All the fields are the same as DailyRollingFileAppender, except log4j.appender.Daily.ArchivedFilename which is where to put the archived files.
	log4j.rootLogger=INFO, Daily
	log4j.appender.Daily.layout.ConversionPattern=%p %c %d{dd-MMM-yyyy HH:mm:ss} - %m%n
3) The rest should be obvious, if not you're stuck reading this.

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 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
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package fmt.log4j;

import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.Locale;
import java.util.TimeZone;

import org.apache.log4j.FileAppender;
import org.apache.log4j.Layout;
import org.apache.log4j.helpers.LogLog;
import org.apache.log4j.spi.LoggingEvent;

      DailyRollingFileAppender extends {@link FileAppender} so that the
      underlying file is rolled over at a user chosen frequency.

The rolling schedule is specified by the DatePattern option. This pattern should follow the {@link SimpleDateFormat} conventions. In particular, you must escape literal text within a pair of single quotes. A formatted version of the date pattern is used as the suffix for the rolled file name.

For example, if the File option is set to /foo/bar.log and the DatePattern set to '.'yyyy-MM-dd, on 2001-02-16 at midnight, the logging file /foo/bar.log will be copied to /foo/bar.log.2001-02-16 and logging for 2001-02-17 will continue in /foo/bar.log until it rolls over the next day.

Is is possible to specify monthly, weekly, half-daily, daily, hourly, or minutely rollover schedules.

DatePattern Rollover schedule Example
'.'yyyy-MM Rollover at the beginning of each month At midnight of May 31st, 2002 /foo/bar.log will be copied to /foo/bar.log.2002-05. Logging for the month of June will be output to /foo/bar.log until it is also rolled over the next month.
'.'yyyy-ww Rollover at the first day of each week. The first day of the week depends on the locale. Assuming the first day of the week is Sunday, on Saturday midnight, June 9th 2002, the file /foo/bar.log will be copied to /foo/bar.log.2002-23. Logging for the 24th week of 2002 will be output to /foo/bar.log until it is rolled over the next week.
'.'yyyy-MM-dd Rollover at midnight each day. At midnight, on March 8th, 2002, /foo/bar.log will be copied to /foo/bar.log.2002-03-08. Logging for the 9th day of March will be output to /foo/bar.log until it is rolled over the next day.
'.'yyyy-MM-dd-a Rollover at midnight and midday of each day. At noon, on March 9th, 2002, /foo/bar.log will be copied to /foo/bar.log.2002-03-09-AM. Logging for the afternoon of the 9th will be output to /foo/bar.log until it is rolled over at midnight.
'.'yyyy-MM-dd-HH Rollover at the top of every hour. At approximately 11:00.000 o'clock on March 9th, 2002, /foo/bar.log will be copied to /foo/bar.log.2002-03-09-10. Logging for the 11th hour of the 9th of March will be output to /foo/bar.log until it is rolled over at the beginning of the next hour.
'.'yyyy-MM-dd-HH-mm Rollover at the beginning of every minute. At approximately 11:23,000, on March 9th, 2001, /foo/bar.log will be copied to /foo/bar.log.2001-03-09-10-22. Logging for the minute of 11:23 (9th of March) will be output to /foo/bar.log until it is rolled over the next minute.

Do not use the colon ":" character in anywhere in the DatePattern option. The text before the colon is interpeted as the protocol specificaion of a URL which is probably not what you want. @author Eirik Lygre @author Ceki Gülcü */ public class DailyRollingFileAppenderToDirectories extends FileAppender { // The code assumes that the following constants are in a increasing // sequence. static final int TOP_OF_TROUBLE = -1; static final int TOP_OF_MINUTE = 0; static final int TOP_OF_HOUR = 1; static final int HALF_DAY = 2; static final int TOP_OF_DAY = 3; static final int TOP_OF_WEEK = 4; static final int TOP_OF_MONTH = 5; /** * The date pattern. By default, the pattern is set to "'.'yyyy-MM-dd" * meaning daily rollover. */ private String datePattern = "'.'yyyy-MM-dd"; /** * The log file will be renamed to the value of the scheduledFilename * variable when the next interval is entered. For example, if the rollover * period is one hour, the log file will be renamed to the value of * "scheduledFilename" at the beginning of the next hour. * * The precise time when a rollover occurs depends on logging activity. */ private String scheduledFilename; /** * The File parameter defines the current log file. * The ArchivedFilename parameter defines where to put log files when * the next interval is entered. See above comment about intervals. * The archivedFilename is a java.util.SimpleDateFormat and can include * directory structures /'s. * Example: * log4j.appender.Daily.ArchivedFilename='C:'/'usr'/yyyy-MM/dd/HH-mm-SS'.log' **/ private String archivedFilename; public String getArchivedFilename() { return archivedFilename; } public void setArchivedFilename(String archivedFilename) { this.archivedFilename = archivedFilename; } /** * The next time we estimate a rollover should occur. */ private long nextCheck = System.currentTimeMillis() - 1; Date now = new Date(); SimpleDateFormat sdf, adf; RollingCalendar rc = new RollingCalendar(); int checkPeriod = TOP_OF_TROUBLE; // The gmtTimeZone is used only in computeCheckPeriod() method. static final TimeZone gmtTimeZone = TimeZone.getTimeZone("GMT"); /** * The default constructor does nothing. */ public DailyRollingFileAppenderToDirectories() { } /** * Instantiate a DailyRollingFileAppender and open the file * designated by filename. The opened filename will become the * ouput destination for this appender. */ public DailyRollingFileAppenderToDirectories(Layout layout, String filename, String datePattern) throws IOException { super(layout, filename, true); this.datePattern = datePattern; activateOptions(); } /** * The DatePattern takes a string in the same format as expected by * {@link SimpleDateFormat}. This options determines the rollover schedule. */ public void setDatePattern(String pattern) { datePattern = pattern; } /** Returns the value of the DatePattern option. */ public String getDatePattern() { return datePattern; } public void activateOptions() { super.activateOptions(); if (datePattern != null && fileName != null) { now.setTime(System.currentTimeMillis()); sdf = new SimpleDateFormat(datePattern); adf = new SimpleDateFormat(archivedFilename); int type = computeCheckPeriod(); printPeriodicity(type); rc.setType(type); File file = new File(fileName); //scheduledFilename = fileName + "a"+ sdf.format(new Date(file.lastModified())); scheduledFilename = adf.format(new Date(file.lastModified())); createDirectories(new File(scheduledFilename)); } else { LogLog.error("Either File or DatePattern options are not set for appender ["+ name + "]."); } } /** * Creates Directories to move files into. * This step is neccessary because you cannot move a file to a location that does not yet exist. * @param target file you want to move */ void createDirectories(File target) { File parentDir = new File(target.getParent()); if (!parentDir.exists()) { parentDir.mkdirs(); } } void printPeriodicity(int type) { switch (type) { case TOP_OF_MINUTE: LogLog.debug("Appender [" + name + "] to be rolled every minute."); break; case TOP_OF_HOUR: LogLog.debug("Appender [" + name + "] to be rolled on top of every hour."); break; case HALF_DAY: LogLog.debug("Appender [" + name + "] to be rolled at midday and midnight."); break; case TOP_OF_DAY: LogLog.debug("Appender [" + name + "] to be rolled at midnight."); break; case TOP_OF_WEEK: LogLog.debug("Appender [" + name + "] to be rolled at start of week."); break; case TOP_OF_MONTH: LogLog.debug("Appender [" + name + "] to be rolled at start of every month."); break; default: LogLog.warn("Unknown periodicity for appender [" + name + "]."); } } // This method computes the roll over period by looping over the // periods, starting with the shortest, and stopping when the r0 is // different from from r1, where r0 is the epoch formatted according // the datePattern (supplied by the user) and r1 is the // epoch+nextMillis(i) formatted according to datePattern. All date // formatting is done in GMT and not local format because the test // logic is based on comparisons relative to 1970-01-01 00:00:00 // GMT (the epoch). int computeCheckPeriod() { RollingCalendar rollingCalendar = new RollingCalendar(gmtTimeZone, Locale.ENGLISH); // set sate to 1970-01-01 00:00:00 GMT Date epoch = new Date(0); if (datePattern != null) { for (int i = TOP_OF_MINUTE; i <= TOP_OF_MONTH; i++) { SimpleDateFormat simpleDateFormat = new SimpleDateFormat( datePattern); simpleDateFormat.setTimeZone(gmtTimeZone); // do all date // formatting in GMT String r0 = simpleDateFormat.format(epoch); rollingCalendar.setType(i); Date next = new Date(rollingCalendar.getNextCheckMillis(epoch)); String r1 = simpleDateFormat.format(next); // System.out.println("Type = "+i+", r0 = "+r0+", r1 = "+r1); if (r0 != null && r1 != null && !r0.equals(r1)) { return i; } } } return TOP_OF_TROUBLE; // Deliberately head for trouble... } /** * Rollover the current file to a new file. */ void rollOver() throws IOException { /* Compute filename, but only if datePattern is specified */ if (datePattern == null) { getErrorHandler() .error("Missing DatePattern option in rollOver()."); return; } // String datedFilename = fileName+"b"+sdf.format(now); String datedFilename = adf.format(now); // It is too early to roll over because we are still within the // bounds of the current interval. Rollover will occur once the // next interval is reached. if (scheduledFilename.equals(datedFilename)) { return; } // close current file, and rename it to datedFilename this.closeFile(); File target = new File(scheduledFilename); if (target.exists()) { target.delete(); } else { createDirectories(target); } File file = new File(fileName); boolean result = file.renameTo(target); if (result) { LogLog.debug(fileName + " -> " + scheduledFilename); } else { LogLog.error("Failed to rename [" + fileName + "] to [" + scheduledFilename + "]."); } try { // This will also close the file. This is OK since multiple // close operations are safe. this.setFile(fileName, false, this.bufferedIO, this.bufferSize); } catch (IOException e) { getErrorHandler().error( "setFile(" + fileName + ", false) call failed."); } scheduledFilename = datedFilename; } /** * This method differentiates DailyRollingFileAppender from its super class. * *

* Before actually logging, this method will check whether it is time to do * a rollover. If it is, it will schedule the next rollover time and then * rollover. * */ protected void subAppend(LoggingEvent event) { long n = System.currentTimeMillis(); if (n >= nextCheck) { now.setTime(n); nextCheck = rc.getNextCheckMillis(now); try { rollOver(); } catch (IOException ioe) { LogLog.error("rollOver() failed.", ioe); } } super.subAppend(event); } } /** * RollingCalendar is a helper class to DailyRollingFileAppender. Given a * periodicity type and the current time, it computes the start of the next * interval. * */ class RollingCalendar extends GregorianCalendar { private static final long serialVersionUID = -3560331770601814177L; int type = DailyRollingFileAppenderToDirectories.TOP_OF_TROUBLE; RollingCalendar() { super(); } RollingCalendar(TimeZone tz, Locale locale) { super(tz, locale); } void setType(int type) { this.type = type; } public long getNextCheckMillis(Date now) { return getNextCheckDate(now).getTime(); } public Date getNextCheckDate(Date now) { this.setTime(now); switch (type) { case DailyRollingFileAppenderToDirectories.TOP_OF_MINUTE: this.set(Calendar.SECOND, 0); this.set(Calendar.MILLISECOND, 0); this.add(Calendar.MINUTE, 1); break; case DailyRollingFileAppenderToDirectories.TOP_OF_HOUR: this.set(Calendar.MINUTE, 0); this.set(Calendar.SECOND, 0); this.set(Calendar.MILLISECOND, 0); this.add(Calendar.HOUR_OF_DAY, 1); break; case DailyRollingFileAppenderToDirectories.HALF_DAY: this.set(Calendar.MINUTE, 0); this.set(Calendar.SECOND, 0); this.set(Calendar.MILLISECOND, 0); int hour = get(Calendar.HOUR_OF_DAY); if (hour < 12) { this.set(Calendar.HOUR_OF_DAY, 12); } else { this.set(Calendar.HOUR_OF_DAY, 0); this.add(Calendar.DAY_OF_MONTH, 1); } break; case DailyRollingFileAppenderToDirectories.TOP_OF_DAY: this.set(Calendar.HOUR_OF_DAY, 0); this.set(Calendar.MINUTE, 0); this.set(Calendar.SECOND, 0); this.set(Calendar.MILLISECOND, 0); this.add(Calendar.DATE, 1); break; case DailyRollingFileAppenderToDirectories.TOP_OF_WEEK: this.set(Calendar.DAY_OF_WEEK, getFirstDayOfWeek()); this.set(Calendar.HOUR_OF_DAY, 0); this.set(Calendar.MINUTE, 0); this.set(Calendar.SECOND, 0); this.set(Calendar.MILLISECOND, 0); this.add(Calendar.WEEK_OF_YEAR, 1); break; case DailyRollingFileAppenderToDirectories.TOP_OF_MONTH: this.set(Calendar.DATE, 1); this.set(Calendar.HOUR_OF_DAY, 0); this.set(Calendar.MINUTE, 0); this.set(Calendar.SECOND, 0); this.set(Calendar.MILLISECOND, 0); this.add(Calendar.MONTH, 1); break; default: throw new IllegalStateException("Unknown periodicity type."); } return getTime(); } }