@Override
  int offsetToLogicalColumn(int offset) {
    if (myCodePoint2Offset == null) return offset;
    if (offset == getLength()) return myCodePoint2Offset.length;
    int i = Arrays.binarySearch(myCodePoint2Offset, (short)offset);
    assert i >= 0;
    return i;
  }
@Override
  int offsetToLogicalColumn(int offset)