/**
  * Set maximum depth of this diagnostic context. If the current
  * depth is smaller or equal to <var>maxDepth</var>, then no
  * action is taken.
  *
  * <p>This method is a convenient alternative to multiple 
  * {@link pop()} calls. Moreover, it is often the case that at 
  * the end of complex call sequences, the depth of the NDC is
  * unpredictable. The {@link setMaxDepth()} method circumvents
  * this problem.
  *
  * @param integer $maxDepth
  * @see getDepth()
  */
 public static function setMaxDepth($maxDepth)
 {
     $maxDepth = (int) $maxDepth;
     if (Payone_Log4php_LoggerNDC::getDepth() > $maxDepth) {
         self::$stack = array_slice(self::$stack, 0, $maxDepth);
     }
 }