Bug 32531 NPE importing preferences
Build id: 200302211557 Got error messages when importing preferences. I couldn't reproduce the problem anymore. Will attach stack traces (two generated in a row). Top entries are: java.lang.NullPointerException at org.eclipse.jdt.internal.ui.packageview.PackageExplorerContentProvider.rootsAndC ontainers(PackageExplorerContentProvider.java:153) at org.eclipse.jdt.internal.ui.packageview.PackageExplorerContentProvider.getChildr en(PackageExplorerContentProvider.java:131) at org.eclipse.jdt.internal.ui.packageview.PackageExplorerPart$4.getFilteredChildre n(PackageExplorerPart.java:352) at org.eclipse.jface.viewers.StructuredViewer.getSortedChildren (StructuredViewer.java:555) at org.eclipse.jface.viewers.AbstractTreeViewer.updateChildren (AbstractTreeViewer.java:1282) at org.eclipse.jface.viewers.AbstractTreeViewer.internalRefresh (AbstractTreeViewer.java:925) at org.eclipse.jface.viewers.AbstractTreeViewer.internalRefresh (AbstractTreeViewer.java:934) at org.eclipse.jface.viewers.AbstractTreeViewer.internalRefresh (AbstractTreeViewer.java:895) at org.eclipse.jface.viewers.AbstractTreeViewer.internalRefresh (AbstractTreeViewer.java:881) at org.eclipse.jface.viewers.StructuredViewer$7.run(StructuredViewer.java:858) at org.eclipse.jface.viewers.StructuredViewer.preservingSelection (StructuredViewer.java:798) at org.eclipse.jface.viewers.StructuredViewer.refresh(StructuredViewer.java:856) at org.eclipse.jface.viewers.StructuredViewer.refresh(StructuredViewer.java:818) at org.eclipse.jdt.internal.ui.packageview.PackageExplorerPart.propertyChange (PackageExplorerPart.java:1062)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerContentProvider.java
public Object getParent(Object child) {
		if (needsToDelegate(child)) {
			return fPackageFragmentProvider.getParent(child);
		} else
			return super.getParent(child);
	}
	/**
	 * Returns the given objects with the resources of the parent.
	 */
	private Object[] getWithParentsResources(Object[] existingObject, Object parent) {
		Object[] objects= super.getChildren(parent);
		List list= new ArrayList();
		
		for (int i= 0; i < objects.length; i++) {
			Object object= objects[i];
			if (!(object instanceof IPackageFragment)) {
				list.add(object);
			}
		}
		if (existingObject != null)
			list.addAll(Arrays.asList(existingObject));
		return list.toArray();
	}
	/* (non-Javadoc)
	 * Method declared on IContentProvider.
	 */
	public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
		super.inputChanged(viewer, oldInput, newInput);
		fPackageFragmentProvider.inputChanged(viewer, oldInput, newInput);
		fViewer= (TreeViewer)viewer;