private static Collection4 collectNames(Class[] classes) {
   Collection4 names = new Collection4();
   for (int classIdx = 0; classIdx < classes.length; classIdx++) {
     names.add(classes[classIdx].getName());
   }
   return names;
 }
 public static void main(String[] args) throws Exception {
   ClassLoader parent = ExcludingClassLoader.class.getClassLoader();
   String excName = ExcludingClassLoader.class.getName();
   Collection4 excluded = new Collection4();
   ClassLoader incLoader = new ExcludingClassLoader(parent, excluded);
   System.out.println(incLoader.loadClass(excName));
   excluded.add(excName);
   try {
     System.out.println(incLoader.loadClass(excName));
   } catch (ClassNotFoundException exc) {
     System.out.println("Ok, not found.");
   }
 }