这是使用Proxy类的纯Java实现：
import java.lang.reflect.*;import java.util.*;public class Demo{ public static void main(String[] args) { Map<String, String> map = new HashMap<String, String>(); map.put("onStart", "abc"); map.put("onEnd", "def"); Library library = new LibraryProxy(map, new LibraryImpl()).proxy(); library.onStart(); library.onEnd(); library.onRun(); }}interface Library{ void onStart(); void onEnd(); void onRun();}class LibraryImpl{ public void abc() { System.out.println("Start"); } public void def() { System.out.println("End"); }}class LibraryProxy implements InvocationHandler{ Map<String, String> map; Object impl; public LibraryProxy(Map<String, String> map, Object impl) { this.map = map; this.impl = impl; } public Library proxy() { return (Library) Proxy.newProxyInstance(Library.class.getClassLoader(), new Class[] { Library.class }, this); } @Override public Object invoke(Object proxy, Method m, Object[] args) throws Throwable { Object res = null; String name = map.get(m.getName()); if (name == null) { System.out.println("[" + m.getName() + " is not defined]"); } else { m = impl.getClass().getMethod(name, m.getParameterTypes()); res = m.invoke(impl, args); } System.out.println("super duper"); return res; }}输出：
Startsuper duperEndsuper duper[onRun is not defined]super duper
