Bug 55884 Loading a user library from file does not warn when overwriting an existing library [build path]
Works in I2004032400010 + plug-in export for I200403240800 Add library 'mylib'. Save it. Change it. Load library from file. ==> should warn that 'mylib' gets changed.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/UserLibraryPreferencePage.java
PreferencesMessages.getString("UserLibraryPreferencePage.libraries.addjar.button"), 
				PreferencesMessages.getString("UserLibraryPreferencePage.libraries.remove.button"), 
				null,
				PreferencesMessages.getString("UserLibraryPreferencePage.libraries.load.button"), 
				PreferencesMessages.getString("UserLibraryPreferencePage.libraries.save.button") 
		};
		
		fLibraryList= new TreeListDialogField(adapter, buttonLabels, new CPListLabelProvider());
		fLibraryList.setLabelText(PreferencesMessages.getString("UserLibraryPreferencePage.libraries.label")); 
		
		String[] names= JavaCore.getUserLibraryNames();
		ArrayList elements= new ArrayList();
		
		IJavaProject jproject= getDummyProject();
		for (int i= 0; i < names.length; i++) {
			IPath path= new Path(JavaCore.USER_LIBRARY_CONTAINER_ID).append(names[i]);
			try {
				IClasspathContainer container= JavaCore.getClasspathContainer(path, jproject);
				elements.add(new CPUserLibraryElement(names[i], container));
			} catch (JavaModelException e) {
				JavaPlugin.log(e);
				
			}
		}
		fLibraryList.setElements(elements);
		fLibraryList.setViewerSorter(new CPListElementSorter());
		
		doSelectionChanged(fLibraryList);  
	}