code: public static int lastIndexOf(String source, char[] chars) {
  
          // now try to find an "sentence ending" char in the text in the "findPointArea"
          int result = -1;
          for (int i = 0; i < chars.length; i++) {
              int pos = source.lastIndexOf(chars[i]);
              if (pos > result) {
                  // found new last char
                  result = pos;
              }
          }
          return result;
      }
docs: Returns the last index of any of the given chars in the given source.<p>
  
  If no char is found, -1 is returned.<p>
  
  @param source the source to check
  @param chars the chars to find
  
  @return the last index of any of the given chars in the given source, or -1