code: public void setPattern(String name, Pattern pattern) {
          if (null == pattern) {
              set(name, null);
          } else {
              set(name, pattern.pattern());
          }
      }
docs: Set the given property to <code>Pattern</code>.
  If the pattern is passed as null, sets the empty pattern which results in
  further calls to getPattern(...) returning the default value.
  
  @param name property name
  @param pattern new value