Bug 81426 Package Explorer shows nothing after drill into working set, then show projects
I200412160800 - switch Package Explorer to working sets - context menu > Go Into a working set - Show > Projects -> view is empty -> view toolbar button 'Up to Working Sets' does not do anything
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
}
					}); 
				}
			}
		} catch(JavaModelException e) {
			
		}
	}
	
	/**
	 * Returns the element contained in the EditorInput
	 */
	Object getElementOfInput(IEditorInput input) {
		if (input instanceof IClassFileEditorInput)
			return ((IClassFileEditorInput)input).getClassFile();
		else if (input instanceof IFileEditorInput)
			return ((IFileEditorInput)input).getFile();
		else if (input instanceof JarEntryEditorInput)
			return ((JarEntryEditorInput)input).getStorage();
		return null;
	}
	
	/**
 	 * Returns the Viewer.
 	 */
	TreeViewer getViewer() {
		return fViewer;
	}
	
	/**