public  void activateOptions() 
{

}

No options to activate.

 public String format(LoggingEvent event) 
{
    // Reset working buffer. If the buffer is too large, then we need a new
    // one in order to avoid the penalty of creating a large array.
    if(buf.capacity()  > UPPER_LIMIT) {
      buf = new StringBuffer(DEFAULT_SIZE);
    } else {
      buf.setLength(0);
    }
    // We yield to the \r\n heresy.
    buf.append("< log4j:event logger=\"");
    buf.append(Transform.escapeTags(event.getLoggerName()));
    buf.append("\" timestamp=\"");
    buf.append(event.timeStamp);
    buf.append("\" level=\"");
    buf.append(Transform.escapeTags(String.valueOf(event.getLevel())));
    buf.append("\" thread=\"");
    buf.append(Transform.escapeTags(event.getThreadName()));
    buf.append("\" >\r\n");
    buf.append("< log4j:message >< ![CDATA[");
    // Append the rendered message. Also make sure to escape any
    // existing CDATA sections.
    Transform.appendEscapingCDATA(buf, event.getRenderedMessage());
    buf.append("]] >< /log4j:message >\r\n");       
    String ndc = event.getNDC();
    if(ndc != null) {
      buf.append("< log4j:NDC >< ![CDATA[");
      Transform.appendEscapingCDATA(buf, ndc);
      buf.append("]] >< /log4j:NDC >\r\n");       
    }
    String[] s = event.getThrowableStrRep();
    if(s != null) {
      buf.append("< log4j:throwable >< ![CDATA[");
      for(int i = 0; i <  s.length; i++) {
          Transform.appendEscapingCDATA(buf, s[i]);
	      buf.append("\r\n");
      }
      buf.append("]] >< /log4j:throwable >\r\n");
    }
    if(locationInfo) { 
      LocationInfo locationInfo = event.getLocationInformation();	
      buf.append("< log4j:locationInfo class=\"");
      buf.append(Transform.escapeTags(locationInfo.getClassName()));
      buf.append("\" method=\"");
      buf.append(Transform.escapeTags(locationInfo.getMethodName()));
      buf.append("\" file=\"");
      buf.append(Transform.escapeTags(locationInfo.getFileName()));
      buf.append("\" line=\"");
      buf.append(locationInfo.getLineNumber());
      buf.append("\"/ >\r\n");
    }
    if (properties) {
        Set keySet = event.getPropertyKeySet();
        if (keySet.size()  > 0) {
            buf.append("< log4j:properties >\r\n");
            Object[] keys = keySet.toArray();
            Arrays.sort(keys);
            for (int i = 0; i <  keys.length; i++) {
                String key = keys[i].toString();
                Object val = event.getMDC(key);
                if (val != null) {
                    buf.append("< log4j:data name=\"");
                    buf.append(Transform.escapeTags(key));
                    buf.append("\" value=\"");
                    buf.append(Transform.escapeTags(String.valueOf(val)));
                    buf.append("\"/ >\r\n");
                }
            }
            buf.append("< /log4j:properties >\r\n");
        }
    }
    buf.append("< /log4j:event >\r\n\r\n");
    return buf.toString();
}

Formats a org.apache.log4j.spi.LoggingEvent in conformance with the log4j.dtd.

 public boolean getLocationInfo() 
{
    return locationInfo;
}

Returns the current value of the LocationInfo option.

 public boolean getProperties() 
{
      return properties;
}

Gets whether MDC key-value pairs should be output.

 public boolean ignoresThrowable() 
{
    return false;
}

The XMLLayout prints and does not ignore exceptions. Hence the return value false.

 public  void setLocationInfo(boolean flag) 
{
 
    locationInfo = flag;
}

The LocationInfo option takes a boolean value. By default, it is set to false which means there will be no location information output by this layout. If the the option is set to true, then the file name and line number of the statement at the origin of the log statement will be output.

If you are embedding this layout within an org.apache.log4j.net.SMTPAppender then make sure to set the LocationInfo option of that appender as well.

 public  void setProperties(boolean flag) 
{
      properties = flag;
}

Sets whether MDC key-value pairs should be output, default false.