code: static void closeURLClassLoader(final URLClassLoader cl)
     {
        AccessController.doPrivileged(new PrivilegedAction<Object>()
        {
           public Object run()
           {
              if (cl != null)
              {
                 try
                 {
                    cl.close();
                 }
                 catch (IOException ioe)
                 {
                    // Ignore
                 }
              }
  
              return null;
           }
        });
     }
docs: Close an URLClassLoader
  @param cl The class loader