Bug 11770 java browsing: multi-selection disabled in 2 of 4 views
multi selection is disabled in the package and type views but it's enabled in project and member views
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/browsing/JavaBrowsingPart.java
adjustInputAndSetSelection(element);
					return;
				}
			}
			if (ei instanceof IFileEditorInput) {
				IFile file= ((IFileEditorInput)ei).getFile();
				IJavaElement je= (IJavaElement)file.getAdapter(IJavaElement.class);
				if (je == null) {
					setSelection(null, false);
					return;
				}
				adjustInputAndSetSelection(je);
			} else if (ei instanceof IClassFileEditorInput) {
				IClassFile cf= ((IClassFileEditorInput)ei).getClassFile();
				adjustInputAndSetSelection(cf);
			}
			return;
		}
	}
	
	/**
	 * 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();