Spring代理模式

二者区别：

静态代理模式:
灵活性不强；如果有1000个dao;就有1000个代理类；没有做到通用性

静态代理模式:

package StaticProxy;

public interface PersonDao {
    
    public void sava();
    
    public void update();

}

package StaticProxy;

public class PersonDaoimpl implements PersonDao {

    public String user = null;
    PersonDaoimpl(){}
    /**
     * @return the user
     */
    public String getUser() {
        return user;
    }

    /**
     * @param user the user to set
     */
    public void setUser(String user) {
        this.user = user;
    }
    
    PersonDaoimpl(String user){
        this.user = user;
    }
    
    @Override
    public void sava() {
        // TODO Auto-generated method stub
        System.out.println("进入方法");
    }

    @Override
    public void update() {
        // TODO Auto-generated method stub
        
    }

}

package StaticProxy;
import JDKProxy.impl.PersonDaoImpl;

//静态代理类

public class personproxy implements PersonDao{

    public PersonDaoimpl persondaoimpl;
    
    public personproxy(PersonDaoimpl persondaoimpl){
        this.persondaoimpl = persondaoimpl;
    }
    
    @Override
    public void sava() {
        // TODO Auto-generated method stub
        if(persondaoimpl.getUser() != null){
            persondaoimpl.sava();
        }
    }

    @Override
    public void update() {
        // TODO Auto-generated method stub
        
    }
    
}

测试类：

package StaticProxy;

public class Test {
    
    public static void main(String[] args) {
        //创建代理类
        personproxy pro  = new personproxy(new PersonDaoimpl());
        pro.sava();
    }

}

动态代理模式：
JDK : proxy
要求:目标类要有实现接口

package JDKProxy;
//接口
public interface PersonDao {
    
    public void sava(String name);
    public void update(String name);
    public String getUsername(String name);

}

package JDKProxy.impl;

import JDKProxy.PersonDao;

public class PersonDaoImpl implements PersonDao {

    private String user = null;
    
    /**
     * @return the user
     */
    public String getUser() {
        return user;
    }

    /**
     * @param user the user to set
     */
    public void setUser(String user) {
        this.user = user;
    }

    public PersonDaoImpl(){}
    
    public PersonDaoImpl(String user){
        this.user = user;
    }
    
    @Override
    public String getUsername(String name) {
    
        System.out.println("这是getusername()方法");
        
        return "oooo";
    }

    @Override
    public void sava(String name) {
        
        System.out.println("这是save()方法");
        
    }

    @Override
    public void update(String name) {
        
        System.out.println("这是update()方法");
        
    }

}

package JDKProxy;

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

import JDKProxy.impl.PersonDaoImpl;

/**
 * 代理工厂
 * 
 * @author Administrator
 * 
 */
public class JdkProxyFactory implements InvocationHandler {

    private Object targetObject;

    /**
     * 生成代理对象
     * 
     * @param targetObject
     * @return
     */
    public Object createProxyObject(Object targetObject) {
        this.targetObject = targetObject;
        // 生成代理对象
        // loader:目标类的加载器
        // interfaces:目标类的所有接口
        // 回调接口类
        return Proxy.newProxyInstance(targetObject.getClass().getClassLoader(),
                targetObject.getClass().getInterfaces(), this);
    }

    /**
     * 代理类回调方法 在调用目标类方法的时候进行回调
     * 调用目标类方法时进行拦截
     */
    @Override//环绕通知
    public Object invoke(Object proxy, Method method, Object[] args)
            throws Throwable {

        PersonDaoImpl persondaoimpl = (PersonDaoImpl) this.targetObject;

        Object invoke = null;
        
        try {

package JDKProxy;

import JDKProxy.impl.PersonDaoImpl;

public class JdkProxyTest {
    public static void main(String[] args) {
        //创建动态代理工厂
        JdkProxyFactory jdkproxy = new JdkProxyFactory();
        //为目标类创建代理对象
        PersonDao persondao = (PersonDao) jdkproxy
                .createProxyObject(new PersonDaoImpl(""));
        persondao.update("xxx");
    }
}

//....begin()：前置通知
            if (persondaoimpl.getUser() != null) {
                // 委派目标对象调用方法:调用的目标方法称为连接点
                invoke = method.invoke(targetObject, args);
            }
            //.....commit()：后置通知
            
        } catch (Exception e) {
            //callback()：异常通知
        }finally{
            //close()：最终通知
        }
        
        return invoke;
    }

}

测试：