How to traverse through a RowKeySet?

Question

I have a RowKeySet for a tree. At a time only one node from this set must be set as selected node.
I have a next and previous button.
When I click next I must traverse to next row in the rowkeyset and when i click previous I must traverse to previous row in the rowkeyset.
I tried this with Iterator. But it has only next() funtion.
somebody please help.

Answer 1

you can try this snippet for your improvisation..
// set newly created node selected
          int rowIndex = rowIterator.getCurrentRowIndex();
          List<JUCtrlHierNodeBinding> kids = null;
          //if Empty Parent node, then rowData still points
          //to parent node. so get children of rowData itself
          if (isEmptyParentNode) {
            kids = rowData.getChildren();
          } else {
            kids = rowData.getParent().getChildren();
          JUCtrlHierNodeBinding treeNode = kids.get(rowIndex);
          List<Key> rowKey = treeNode.getKeyPath();
          selectedRowKeys.add(rowKey);
          // if the parent node is collapsed, it needs to be expanded.
          // if no node is selected, the new node is created at the top level,
          // it means there is no parent node.
          if (nodeSelected)
            Object parentRowKey = tree.getContainerRowKey(rowKey);
            RowKeySet expandedRowKeys = tree.getDisclosedRowKeys();
            Iterator expandIter = expandedRowKeys.iterator();
            boolean parentExpanded = false;
            if (expandIter != null && expandIter.hasNext())
              while (expandIter.hasNext())
                Object expandedRowKey = expandIter.next();
                if (expandedRowKey.equals(parentRowKey))
                  parentExpanded = true;
            if (!parentExpanded)
              expandedRowKeys.add(parentRowKey);
          if (target != null)
            target.setCurrentRowWithKey(row.getKey().toStringFormat(true));
        }