Bug 210448 [Viewers] [JFace] AbstractTreeViewer inputChanged setRedraw should be in try/finally
The inputChanged method on the AbstractTreeViewer makes use of setRedraw, which is good, but it doesn't use a try/finally block as per recommendations. If an exception is thrown from within one of the methods called, redraw will remain false. Additionally, the commented out portion is fine, but the fact that we have conditionals in the code that always evaluate to true is less fine. When we're ready to actually determine when to use redraw we could put them back in. Current code: protected void inputChanged(Object input, Object oldInput) { preservingSelection(new Runnable() { public void run() { Control tree = getControl(); boolean useRedraw = true; // (size > REDRAW_THRESHOLD) || (table.getItemCount() > // REDRAW_THRESHOLD); if (useRedraw) { tree.setRedraw(false); } removeAll(tree); tree.setData(getRoot()); internalInitializeTree(tree); if (useRedraw) { tree.setRedraw(true); } } }); } Suggestion: protected void inputChanged(Object input, Object oldInput) { preservingSelection(new Runnable() { public void run() { Control tree = getControl(); try { tree.setRedraw(false); removeAll(tree); tree.setData(getRoot()); internalInitializeTree(tree); } finally { tree.setRedraw(true); } } }); }
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
*            The parent widget
	 * @param sorter
	 *            The sorter to use.
	 * @param startIndex
	 *            the start index to start search for position from this allows
	 *            optimizing search for multiple elements that are sorted
	 *            themselves.
	 * @param element
	 *            element to find position for.
	 * @param currentSize
	 *            the current size of the collection
	 * @return the index to use when inserting the element.
	 *
	 */
	/**
	 * Returns the index where the item should be inserted.
	 *
	 * @param parent
	 *            The parent widget the element will be inserted into.
	 * @param element
	 *            The element to insert.
	 * @return the index of the element
	 */
	protected int indexForElement(Widget parent, Object element) {
		ViewerComparator comparator = getComparator();
		TreePath parentPath = internalGetSorterParentPath(parent, comparator);
		Item[] items = getChildren(parent);
		int count = items.length;
		if (comparator == null) {
			return count;