spring中提供了兩種動態代理的方式，分別是Java Proxy以及cglib

JavaProxy只能代理接口，而cglib是通過繼承的方式，實現對類的代理

添加一個接口以及對應的實現類

public interface HelloInterface { void sayHello();}

public class HelloInterfaceImpl implements HelloInterface { @Override public void sayHello() { System.out.println('hello'); }}

JavaProxy通過實現InvocationHandler實現代理

public class CustomInvocationHandler implements InvocationHandler { private HelloInterface helloInterface; public CustomInvocationHandler(HelloInterface helloInterface) { this.helloInterface = helloInterface; } @Override public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { System.out.println('before hello for proxy'); Object result = method.invoke(helloInterface, args); System.out.println('after hello for proxy'); return result; }}

而cglib實現MethodInterceptor進行方法上的代理

public class CustomMethodInterceptor implements MethodInterceptor { @Override public Object intercept(Object o, Method method, Object[] objects, MethodProxy methodProxy) throws Throwable { System.out.println('before hello for cglib'); Object result = methodProxy.invokeSuper(o, objects); System.out.println('after hello for cglib'); return result; }}

分別實現調用代碼

public static void main(String[] args) { Enhancer enhancer = new Enhancer(); enhancer.setSuperclass(HelloInterfaceImpl.class); enhancer.setCallback(new CustomMethodInterceptor()); HelloInterface target = (HelloInterface) enhancer.create(); target.sayHello(); CustomInvocationHandler invocationHandler = new CustomInvocationHandler(new HelloInterfaceImpl()); HelloInterface target2 = (HelloInterface) Proxy.newProxyInstance(Demo.class.getClassLoader(), new Class[]{HelloInterface.class}, invocationHandler); target2.sayHello(); }

可以看到對于的代理信息輸出

before hello for cglibhelloafter hello for cglibbefore hello for proxyhelloafter hello for proxy

以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持好吧啦網。