/**
   Produces a formatted string as specified by the conversion pattern.
*/
public String format(LoggingEvent event) {
  // Reset working stringbuffer
  if(sbuf.capacity() > MAX_CAPACITY) {
    sbuf = new StringBuffer(BUF_SIZE);
  } else {
    sbuf.setLength(0);
  }

  PatternConverter c = head;

  while(c != null) {
    c.format(sbuf, event);
    c = c.next;
  }
  return sbuf.toString();
}
 

@Override
protected void finalizeConverter(char c) {
    PatternConverter pc = null;

    switch (c) {
        case 'H':
            pc = new HeaderPatternConverter(formattingInfo);
            currentLiteral.setLength(0);
            break;
    }

    if (pc != null) {
        addConverter(pc);
    } else {
        super.finalizeConverter(c);
    }
}