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
}
		if (element instanceof ICompilationUnit) {
			if (getProvideWorkingCopy()) {
				IJavaElement original= ((IWorkingCopy)element).getOriginalElement();
				if (original != null)
					element= original;
			}
			if (kind == IJavaElementDelta.CHANGED) {
				postRefresh(element);
				updateSelection(delta);
				return;
			}
		}
		
		if ((element instanceof ICompilationUnit) || (element instanceof IClassFile))
			return;
			
		
		if (element instanceof IPackageFragmentRoot && ((flags & IJavaElementDelta.F_ARCHIVE_CONTENT_CHANGED) != 0)) {
			postRefresh(element);
			return;
		}
		
		if (element instanceof IPackageFragmentRoot && (((flags & IJavaElementDelta.F_SOURCEATTACHED) != 0 || ((flags & IJavaElementDelta.F_SOURCEDETACHED)) != 0)))
			postUpdateIcon(element);
			
		if (isClassPathChange(delta)) {
			  
			postRefresh(element.getJavaProject());
			return;