-
- private int start; // start position to iterate from
-
- private int end; // end position to iterate to
-
- // current index in hiddenColumns
- private int currentPosition = 0;
-
- // local copy or reference to hiddenColumns
- private List<Integer> positions = null;
-
- /**
- * Construct an iterator over hiddenColums bounded at
- * [lowerBound,upperBound]
- *
- * @param lowerBound
- * lower bound to iterate from
- * @param upperBound
- * upper bound to iterate to
- * @param useCopyCols
- * whether to make a local copy of hiddenColumns for iteration (set
- * to true if calling from outwith the HiddenColumns class)
- */
- BoundedStartRegionIterator(int lowerBound, int upperBound,
- boolean useCopy)
- {
- start = lowerBound;
- end = upperBound;
-
- try
- {
- if (useCopy)
- {
- // assume that if useCopy is false the calling code has locked
- // hiddenColumns
- LOCK.readLock().lock();
- }
-
- if (hiddenColumns != null)
- {
- positions = new ArrayList<>(hiddenColumns.size());
-
- // navigate to start, keeping count of hidden columns
- int i = 0;
- int hiddenSoFar = 0;
- while ((i < hiddenColumns.size())
- && (hiddenColumns.get(i)[0] < start + hiddenSoFar))
- {
- int[] region = hiddenColumns.get(i);
- hiddenSoFar += region[1] - region[0] + 1;
- i++;
- }
-
- // iterate from start to end, adding start positions of each
- // hidden region. Positions are visible columns count, not absolute
- while (i < hiddenColumns.size()
- && (hiddenColumns.get(i)[0] <= end + hiddenSoFar))
- {
- int[] region = hiddenColumns.get(i);
- positions.add(region[0] - hiddenSoFar);
- hiddenSoFar += region[1] - region[0] + 1;
- i++;
- }
- }
- else
- {
- positions = new ArrayList<>();
- }
- } finally
- {
- if (useCopy)
- {
- LOCK.readLock().unlock();
- }
- }
- }
-
- @Override
- public boolean hasNext()