001- The proxy pattern

002- Static proxy

2.1 Implementation of static proxy

If there are multiple stars to perform , Then use interface oriented programming ：

2.2 The flaw of static proxy

003- A dynamic proxy

3.1 JDK A dynamic proxy （ master ）

（1）JDK Classes and interfaces used by dynamic proxy

（2） Realization JDK A dynamic proxy

package com.bjpowernode.proxy;

import com.bjpowernode.service.Service;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;

/** * */
public class ProxyFactory {
    
    // The member variables in the class are designed as interfaces , Target audience 
    Service target;

    // Incoming target object 
    public ProxyFactory(Service target){
    
        this.target = target;
    }

    // Returns the dynamic proxy object 
    public Object getAgent(){
    
        return Proxy.newProxyInstance(
                //ClassLoader loader,  Class loader , Finish loading the target object 
                target.getClass().getClassLoader(),
                //Class<?>[] interfaces, All interfaces implemented by the target object 
                target.getClass().getInterfaces(),
                //InvocationHandler h, Interface to implement proxy function  , What we passed in is an anonymous internal implementation 
                new InvocationHandler() {
    
                    @Override
                    public Object invoke(
                            // Create proxy object 
                            Object proxy,
                            //method It's the target method sing(),show()
                            Method method,
                            // Parameters of the target method 
                            Object[] args) throws Throwable {
    
                        // Agent function 
                        System.out.println(" Booking time ........");
                        // Agent function 
                        System.out.println(" Booking a venue ........");
                        // The main business function is realized 
                        //target.sing(); Or write dead the method call ,  no 
                        //sing(),show(),one()
                        Object obj = method.invoke(target,args);
                        // Agent function 
                        System.out.println(" Settle the expenses ........");
                        return obj;  // Bear in mind : This is the return value of the target method 
                    }
                }
        );
    }
}

3.2 CGLib A dynamic proxy （ understand ）

（1） characteristic

（2）CGLib Dynamic agent implementation

The simplified version implements ：

Complete the implementation ：

004- summary