public DailyFileAppender() 
{

}

The default constructor does no longer set a default layout nor a default output target.

 public DailyFileAppender(Layout layout,
    String filename) throws IOException 
{
    super(layout, filename);
}

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

The file will be appended to.

 public DailyFileAppender(Layout layout,
    String filename,
    boolean append) throws IOException 
{
    super(layout, filename, append);
}

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

If the append parameter is true, the file will be appended to. Otherwise, the file desginated by filename will be truncated before being opened.

 public  void activateOptions() 
{
    try {
	   setFile(null, super.fileAppend);
    }
    catch(java.io.IOException e) {
	   errorHandler.error("setFile(null,"+fileAppend+") call failed.",
		  	   e, ErrorCode.FILE_OPEN_FAILURE);
    }
}

If the a value for #FILE_OPTION is non-null, then #setFile is called with the values of #FILE_OPTION and #APPEND_OPTION .

 public String[] getOptionStrings() 
{
    return OptionConverter.concatanateArrays(super.getOptionStrings(),
		 new String[] {FILE_NAME_PATTERN_OPTION});
}

Retuns the option names for this component, namely #FILE_NAME_PATTERN_OPTION in addition to the options of FileAppender .

 public synchronized  void setFile(String fileName,
    boolean append) throws IOException 
{
    /* Compute filename, but only if fileNamePattern is specified */
    if (fileNamePattern == null) {
      errorHandler.error("Missing file pattern (" + FILE_NAME_PATTERN_OPTION + ") in setFile().");
      return;
    }
    Date now = new Date();
    fileName = new SimpleDateFormat(fileNamePattern).format (now);
    if (fileName.equals(currentFileName))
      return;
    /* Set up next filename checkpoint */
    DailyFileAppenderCalendar c = new DailyFileAppenderCalendar();
    c.rollToNextDay ();
    nextFilenameComputingMillis = c.getTimeInMillis ();
    currentFileName = fileName;
    super.setFile(fileName, append);
}

Set the current output file. The function will compute a new filename, and open a new file only when the name has changed. The function is automatically called once a day, to allow for daily files -- the purpose of this class.

 public  void setOption(String key,
    String value) 
{
    super.setOption(key, value);    
    if(key.equalsIgnoreCase(FILE_NAME_PATTERN_OPTION)) {
      fileNamePattern = value;
    }
}

Set the options for the appender

 protected  void subAppend(LoggingEvent event) 
{
     
     if (System.currentTimeMillis ()  >= nextFilenameComputingMillis) {
      try {
        setFile (super.fileName, super.fileAppend);
      }
      catch(IOException e) {
        System.err.println("setFile(null, false) call failed.");
        e.printStackTrace();
      }
    }
    super.subAppend(event);
}

This method differentiates RollingFileAppender from its super class.