JAVA的动态代理分析.doc

JAVA的动态代理分析 引导语：在使用动态代理类时，我们必须实现InvocationHandler接口,以下是分享给大家的JAVA动态代理，欢迎阅读了解! 1，被代理类的接口Proxied Java代码 packageTest1; /被代理类需实现的接口 publicinterfaceProxied voiddoSomething(); voiddoSomethingElse(Stringstr); 2，一个Proxied接口的实现类(被代理类) Java代码 packageTest1; publicclassConcreteProxiedimplementsProxied Override publicvoiddoSomething() try Thread.sleep(100); catch(InterruptedExceptione) System.err.println(Error:InterruptedException); System.out.println(this.getClass().getSimpleName() +doSomething.); Override publicvoiddoSomethingElse(Stringstr) try Thread.sleep(150); catch(InterruptedExceptione) System.err.println(Error:InterruptedException); System.out.println(this.getClass().getSimpleName() +doSomethingElse,argument=+str+.); 3，TimingInvocationHandler类，实现了InvocationHandler接口 Java代码 packageTest1; importjava.lang.reflect.InvocationHandler; importjava.lang.reflect.Method; publicclassTimeingInvocationHandlerimplementsInvocationHandler /被代理的对象 privateObjectproxied; publicTimeingInvocationHandler(Objectproxied) xied=proxied; /参数proxy表示代理类的对象 /参数method表示被代理类和代理类都实现的接口的方法对象 /参数args表示方法method的参数数组 Override publicObjectinvoke(Objectproxy,Methodmethod,Objectargs) throwsThrowable System.out.println(method.getDeclaringClass().getName(); longcurrentTimeMillis=System.currentTimeMillis(); Objectret=method.invoke(proxied,args); System.out.println(this.getClass().getSimpleName()+wastestime: +(System.currentTimeMillis()-currentTimeMillis)+ms); returnret; 4，测试类Test Java代码 packageTest1; importjava.lang.reflect.Proxy; publicclassTestProxy publicstaticvoidmain(Stringargs) Proxiedproxied=newConcreteProxied(); proxied.doSomething(); proxied.doSomethingElse(onlyaString); /生成一个代理实例，这个代理实现了Proxied接口 /对这个代理(proxy)的方法的调用会重定向到TimeingInvocationHandler的invoke方法 Proxiedproxy=(Proxied)Proxy.newProxyInstance(Proxied.class .getClassLoader(),/类加载器 newClassProxied.class,/代理要实现的接口 newTimeingInvocationHandler(proxied)/调用处理器 ); proxy.doSomething(); proxy.doSomethingElse(onlyaString); 运行Test类，输出如下： ConcreteProxieddoSomething. ConcreteProxieddoSomethingElse,argument=onlyaString. Test1.Proxied ConcreteProxieddoSomething. TimeingInvocationHandlerwastestime:11