code: @SuppressWarnings("unchecked")
  	private void addURL(URL url) throws Exception {
  		URLClassLoader classLoader = (URLClassLoader) ClassLoader.getSystemClassLoader();
  		Class clazz = URLClassLoader.class;
  		Method method = clazz.getDeclaredMethod("addURL", new Class[] { URL.class });
  		method.setAccessible(true);
  		method.invoke(classLoader, new Object[] { url });
  	}
docs: http://stackoverflow.com/questions/252893/how-do-you-change-the-classpath-within-java