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
}
					setExpanded(item, expanded);
				}
			}
			internalSetExpandedTreePaths(expandedTreePaths, item, childPath);
		}
	}
	/**
	 * Return whether the tree node representing the given element or path can
	 * be expanded. Clients should query expandability by path if the viewer's
	 * content provider is an {@link ITreePathContentProvider}.
	 * <p>
	 * The default implementation of this framework method calls
	 * <code>hasChildren</code> on this viewer's content provider. It may be
	 * overridden if necessary.
	 * </p>
	 *
	 * @param elementOrTreePath
	 *            the element or path
	 * @return <code>true</code> if the tree node representing the given
	 *         element can be expanded, or <code>false</code> if not
	 */
	public boolean isExpandable(Object elementOrTreePath) {
		Object element;
		TreePath path;
		if (elementOrTreePath instanceof TreePath) {
			path = (TreePath) elementOrTreePath;
			element = path.getLastSegment();
		} else {
			element = elementOrTreePath;