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
* is not a {@link TreePathViewerSorter} or if the parent widget is not an
	 * {@link Item} (i.e. is the root of the tree).
	 *
	 * @param parent
	 *            the parent widget
	 * @param comparator
	 *            the sorter
	 * @return the tree path that should be used as the parent path for the
	 *         given widget and sorter
	 */
	private TreePath internalGetSorterParentPath(Widget parent,
			ViewerComparator comparator) {
		TreePath path;
		if (comparator instanceof TreePathViewerSorter
				&& parent instanceof Item) {
			Item item = (Item) parent;
			path = getTreePathFromItem(item);
		} else {
			path = null;
		}
		return path;
	}
	/**
	 * Compare the two elements using the given sorter. If the sorter is a
	 * {@link TreePathViewerSorter}, the provided tree path will be used. If
	 * the tree path is null and the sorter is a tree path sorter, then the
	 * elements are root elements
	 *
	 * @param comparator
	 *            the sorter