我应该如何在运行时动态加载Jars？

我应该如何在运行时动态加载Jars？

方法1

URLClassLoader child = new URLClassLoader(myJar.toURL(), this.getClass().getClassLoader());
Class classToLoad = Class.forName("com.MyClass", true, child);
Method method = classToLoad.getDeclaredMethod("myMethod");
Object instance = classToLoad.newInstance();
Object result = method.invoke(instance);

方法2

File file = ...
URL url = file.toURI().toURL();

URLClassLoader classLoader = (URLClassLoader)ClassLoader.getSystemClassLoader();
Method method = URLClassLoader.class.getDeclaredMethod("addURL", URL.class);
method.setAccessible(true);
method.invoke(classLoader, url);