Bug 258016 [PropertiesView] NPE in org.eclipse.ui.views.properties.PropertySheetViewer
At line 720. If the selection is null this will result in an NPE. Here is the offending code snippet: 714: // get the new selection 715: TreeItem[] sel = new TreeItem[] { selection }; 716: if (sel.length == 0) { 717: setMessage(null); 718: setErrorMessage(null); 719: } else { 720: Object object = sel[0].getData(); // assume single selection It would be better replaced with the following (sorry, no patch, I'm not set up for editing the platform!): // get the new selection TreeItem sel = new TreeItem[] { selection; if (selection == null) { setMessage(null); setErrorMessage(null); } else { Object object = selection.getData(); // assume single selection if (object instanceof IPropertySheetEntry) { // get the entry for this item IPropertySheetEntry activeEntry = (IPropertySheetEntry) object; // display the description for the item setMessage(activeEntry.getDescription()); // activate a cell editor on the selection activateCellEditor(selection); } } In fact, I'm not at all sure why the selection was being wrapped in a single element array at all, I'm guessing a holdover from old code?
bundles/org.eclipse.ui.views/src/org/eclipse/ui/views/properties/PropertySheetViewer.java
private static String MISCELLANEOUS_CATEGORY_NAME = PropertiesMessages.PropertyViewer_misc;
    
    private int columnToEdit = 1;
    private CellEditor cellEditor;
    private IPropertySheetEntryListener entryListener;
    private ICellEditorListener editorListener;
    
    private boolean isShowingCategories = true;
    
    private boolean isShowingExpertProperties = false;
    
    private IStatusLineManager statusLineManager;
    
    private ListenerList activationListeners = new ListenerList();
    
    
    private PropertySheetSorter sorter = new PropertySheetSorter();
    /**
     * Creates a property sheet viewer on a newly-created tree control
     * under the given parent. The viewer has no input, and no root entry.
     * 
     * @param parent
     *            the parent control
     */
    public PropertySheetViewer(Composite parent) {
        tree = new Tree(parent, SWT.FULL_SELECTION | SWT.SINGLE
                | SWT.HIDE_SELECTION);
        
        tree.setLinesVisible(true);
        tree.setHeaderVisible(true);