code: @Override
      protected void onInitialize() {
  
          if (patterns == null && log.isWarnEnabled()) {
  
              // Log somewhat
              log.warn("No Patterns configured for AbstractPatternFilter [" + getClass().getName() + "]. "
                      + "This could imply a configuration problem.");
  
          } else {
              // Complete internal state
              regularExpressions = convert(patterns, patternPrefix);
          }
      }
docs: Compiles the List of Patterns used by this AbstractPatternFilter to match candidates.
  If no patterns are supplied (by configuration or constructor call), no regularExpressions Pattern List will be
  created for use by this AbstractPatternFilter. Instead, some logging is emitted onto the console.
  
  @see #patterns