Bug 52474 UI Blocked when opening Java Perspective during CVS check out
build I20040218 - start eclipse with a new workspace - switch to CVS Repository Exploring perspective - check out a number of projects ( i checkout Platform UI module) - now attempt to switch to the Java Perspective NOTE that at this point the "UI is blocked" dialog is opened. Probably due to the fact that starting the Java Perspective requires the workbench lock? The point here is that this will be a common pattern and it would be nice if we could investigate makeing this scenario work more smoothly.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
}
				} finally {
					fViewer.addSelectionChangedListener(fSelectionListener);
				}
			}
			return true;
		}
		return false;
	}
	
	private boolean isOnClassPath(IFile file) {
		IJavaProject jproject= JavaCore.create(file.getProject());
		return jproject.isOnClasspath(file);
	}
	/**
	 * Returns the element's parent.
	 * 
	 * @return the parent or <code>null</code> if there's no parent
	 */
	private Object getParent(Object element) {
		if (element instanceof IJavaElement)
			return ((IJavaElement)element).getParent();
		else if (element instanceof IResource)
			return ((IResource)element).getParent();
			
		return null;
	}
	
	/**
	 * A compilation unit or class was expanded, expand