code: public boolean add(char[] items, int start, int length) {
      ensureCapacity(size + length);
      for (int i = start, n = start + length; i < n; i++) {
        elements[size++] = items[i];
      }
      return length > 0;
    }
docs: Appends a range of values to the end of this array.
  
  @param items
  The array containing the values to append.
  @param start
  The index into <code>items</code> of the first item to add.
  @param length
  The number of items to add.
  @return A value indicating if the array has changed.