动态代理简介

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public interface IHello { public void hello(String name);}?

public class HelloSpeaker implements IHello { public void hello(String name) { System.out.println("Hello, " + name); }}?

public class LogHandler implements InvocationHandler { private Logger logger = Logger.getLogger(this.getClass().getName()); private Object delegate; public Object bind(Object delegate) { this.delegate = delegate; return Proxy.newProxyInstance(delegate.getClass().getClassLoader(), delegate.getClass().getInterfaces(), this); } public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { Object result = null; try { log("method starts..." + method); result = method.invoke(delegate, args); logger.log(Level.INFO, "method ends..." + method); } catch (Exception e) { log(e.toString()); } return result; } private void log(String message) { logger.log(Level.INFO, message); }}?

public class DynamicProxyDemo { public static void main(String[] args) { LogHandler logHandler = new LogHandler(); IHello helloProxy = (IHello) logHandler.bind(new HelloSpeaker()); helloProxy.hello("Justin"); } }?

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