gistfile1.txt

        @Override
        public void treeNodesRemoved(TreeModelEvent event)
        {
            Object parent = event.getTreePath().getLastPathComponent();
            List<Object> children = getCachedChildren(parent);
            if (children != null)
            {
                // Optimisation: if the children are null then the caller doesn't need to know about them
                // or we would have been asked for them at some point.

                Comparator<Object> comparator = getComparator();
                
                Object[] removedChildren = event.getChildren();
                removedChildren = Arrays.copyOf(removedChildren, removedChildren.length);
                Arrays.sort(removedChildren, comparator);

                // The event we fire out has to be in ascending order.  We'll do the actual removals in reverse though.
                int[] removedChildIndices = new int[removedChildren.length];
                for (int i = removedChildren.length - 1; i >= 0; i--)
                {
                    // This does work:
                    //int removedIndex = children.indexOf(removedChildren[i]);

                    // This does *NOT* work.  Why?
                    int removedIndex = Collections.binarySearch(children, removedChildren[i], comparator);

                    assert removedIndex >= 0;

                    children.remove(removedIndex);
                    removedChildIndices[i] = removedIndex;
                }

                fireTreeNodesRemoved(event.getPath(), removedChildIndices, removedChildren);
            }
        }