@Nullable
    private Integer getUnchangedBoundaryShift(@NotNull Side touchSide,
                                              int equalForward, int equalBackward,
                                              @NotNull Range range1, @NotNull Range range2,
                                              int threshold) {
      List<? extends Line> touchLines = touchSide.select(myData1, myData2);
      int touchStart = touchSide.select(range2.start1, range2.start2);

      int shiftForward = findNextUnimportantLine(touchLines, touchStart, equalForward + 1, threshold);
      int shiftBackward = findPrevUnimportantLine(touchLines, touchStart - 1, equalBackward + 1, threshold);

      return getShift(shiftForward, shiftBackward);
    }
@Nullable
    private Integer getUnchangedBoundaryShift(@NotNull Side touchSide,
                                              int equalForward, int equalBackward,
                                              @NotNull Range range1, @NotNull Range range2,
                                              int threshold)