Bug 73984 Editing user library jar path after path change does not work [build path]
1) Create a directory containing jar file 2) Add this jar file to a new user library 3) Rename directory from 1) 4) Update the path to jar file in user libraries (select old jar reference, select new location in browser, open -> path is not updated, but old path is still used
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/UserLibraryPreferencePage.java
public UserLibraryPreferencePage(String selectedLibrary, boolean createIfNotFound) {
		this();
		if (selectedLibrary != null) {
			int nElements= fLibraryList.getSize();
			for (int i= 0; i < nElements; i++) {
				CPUserLibraryElement curr= (CPUserLibraryElement) fLibraryList.getElement(i);
				if (curr.getName().equals(selectedLibrary)) {
					fLibraryList.selectElements(new StructuredSelection(curr));
					fLibraryList.expandElement(curr, AbstractTreeViewer.ALL_LEVELS);
					break;
				}
			}
			if (createIfNotFound) {
				CPUserLibraryElement elem= new CPUserLibraryElement(selectedLibrary, null);
				fLibraryList.addElement(elem);
				fLibraryList.selectElements(new StructuredSelection(elem));
			}
		}
	}
	
	/*
	 * (non-Javadoc)
	 * @see org.eclipse.jface.dialogs.IDialogPage#createControl(org.eclipse.swt.widgets.Composite)
	 */
	public void createControl(Composite parent) {
		super.createControl(parent);
		WorkbenchHelp.setHelp(getControl(), IJavaHelpContextIds.CP_USERLIBRARIES_PREFERENCE_PAGE);
	}	
	/*
	 * @see PreferencePage#createContents(org.eclipse.swt.widgets.Composite)