54_55 summarizes and analyzes the design principle and structure of the dynamic proxy class, And 54_55 dynamic

54_55 summarizes and analyzes the design principle and structure of the dynamic proxy class, And 54_55 dynamic

Log () is a system log. It can be modularized and hot-swappable by using the aspect programming to insert it around the invoke method.

 

 

 

 

 

 

For the previous code, the yellow part should be extracted and modularized.

 

 

 

 

Target Extraction as a parameter

final ArrayList target=new ArrayList();Collection proxy3 = (Collection) getProxy(target,new MyAdvice());

 

System functions are extracted into an object.

public static Object getProxy(final Object target,final Advice advice) {    Object proxy3 = Proxy.newProxyInstance(            Collection.class.getClassLoader(),             new Class[]{Collection.class},             new InvocationHandler(){                @Override                public Object invoke(Object proxy, Method method,                        Object[] args) throws Throwable {                    advice.beforeMethod(method);                    Object reVal=method.invoke(target, args);                    advice.afterMethod(method);                    return reVal;                }            }        );    return proxy3;}

 

Notification interface-Contract

package com.itcast.day3;import java.lang.reflect.Method;public interface Advice {    public void beforeMethod(Method method);    public void afterMethod(Method method);}

 

Implementation of the contract-usually the most workload when Spring aop is used at work

package com.itcast.day3;import java.lang.reflect.Method;public class MyAdvice implements Advice {    long beginTime=0;    @Override    public void beforeMethod(Method method) {        beginTime=System.currentTimeMillis();    }    @Override    public void afterMethod(Method method) {        long endTime=System.currentTimeMillis();        System.out.println(method.getName()+" running "+(endTime-beginTime));    }}

When using spring aop, you only need to do two things.

1. Configure Advice

2. Configure target