setPositionsInRange(newGapStart, gapStart, false);
int adjIndex = searchFirst(newGapStart); int count = marks.size(); for (int i = adjIndex; i < count; i++) { Mark m = (Mark) marks.get(i); if (m.mark > gapStart) break; m.mark = gapEnd; }
  protected void shiftGapStartDown(int newGapStart)  {    if (newGapStart == gapStart)      return;    assert newGapStart < gapStart : "The new gap start must be less than the "                                    + "old gap start.";    setPositionsInRange(newGapStart, gapStart, false);    gapStart = newGapStart;  }