动态代理jdk 和cglib

jdk方式

package com.kite.dao.jdkproxy;

/**
 * 定义一个person类
 * @author admin
 *
 */
public class Person
{
    private Long pid;
    private String pname;
    public Long getPid()
    {
        return pid;
    }
    public void setPid(Long pid)
    {
        this.pid = pid;
    }
    public String getPname()
    {
        return pname;
    }
    public void setPname(String pname)
    {
        this.pname = pname;
    }
}

package com.kite.dao.jdkproxy;

import java.util.List;
/**
 * 定义一个接口
 * @author admin
 *
 */
public interface PersonDao
{
    public void savePerson();
    public void updatePerson();
    public void deletePerson();
    public List<Person> getPerson();
}

package com.kite.dao.jdkproxy;

import java.util.ArrayList;
import java.util.List;
/**
 * 实现接口
 * @author admin
 *
 */
public class PersonDaoImpl implements PersonDao
{

    @Override
    public void savePerson()
    {
        System.out.println("save person");
    }

    @Override
    public void updatePerson()
    {
        System.out.println("update person");
    }

    @Override
    public void deletePerson()
    {
        System.out.println("delete person");
    }

    @Override
    public List<Person> getPerson()
    {
        List<Person> list = new ArrayList<Person>();
        Person p = new Person();
        p.setPname("kite");
        p.setPid(1L);
        list.add(p);
        for(Person person : list)
        {
            System.out.println(person.getPname());
        }
        return null;
    }
    
}

package com.kite.dao.jdkproxy;
/**
 * 模仿事物
 * @author admin
 *
 */
public class Transaction
{
    public void beginTransaction()
    {
        System.out.println("begin transaction");
    }
    public void commitTransaction()
    {
        System.out.println("commit transaction");
    }
    
    
}

package com.kite.dao.jdkproxy;

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

/**
 * 代理类 
 * @author admin
 *
 */
public class PersonDaoInteceptor implements InvocationHandler
{

    private Transaction transaction;
    public Object target;
    public PersonDaoInteceptor(Object target, Transaction transaction)
    {
        this.transaction = transaction;
        this.target = target;
    }
    @Override
    public Object invoke(Object proxy, Method method, Object[] args)
            throws Throwable
    {
        Object obj;
        String methodName = method.getName();
        if("savePerson".equals(methodName) || "updatePerson".equals(methodName) || "deletePerson".equals(methodName))
        {
            transaction.beginTransaction();
            obj = method.invoke(target, args);
            transaction.commitTransaction();
        }else
        {
            obj = method.invoke(target, args);
        }
        return obj;
    }

}

package com.kite.dao.jdkproxy;

import java.lang.reflect.Proxy;

import org.junit.Test;
/**
*测试类
*/
public class PersonDaoTest
{
    @Test
    public void test()
    {
        Transaction transaction = new Transaction();
        PersonDao personDao = new PersonDaoImpl();
        //拦截器
        PersonDaoInteceptor interceptor = new PersonDaoInteceptor(personDao, transaction);
        //获得代理对象
        PersonDao proxy = (PersonDao) Proxy.newProxyInstance(personDao.getClass().getClassLoader(), personDao.getClass().getInterfaces(), interceptor);
        //调用目标方法
        proxy.getPerson();
    }
}

cglib方式  只需要修改

package com.kite.dao.jdkproxy;

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

/**
 * 代理类 
 * @author admin
 *
 */
public class PersonDaoInteceptor implements InvocationHandler
{

    private Transaction transaction;
    public Object target;
    public PersonDaoInteceptor(Object target, Transaction transaction)
    {
        this.transaction = transaction;
        this.target = target;
    }
    @Override
    public Object invoke(Object proxy, Method method, Object[] args)
            throws Throwable
    {
        Object obj;
        String methodName = method.getName();
        if("savePerson".equals(methodName) || "updatePerson".equals(methodName) || "deletePerson".equals(methodName))
        {
            transaction.beginTransaction();
            obj = method.invoke(target, args);
            transaction.commitTransaction();
        }else
        {
            obj = method.invoke(target, args);
        }
        return obj;
    }

}

测试

package com.kite.dao.cglibproxy;

import java.lang.reflect.Proxy;

import org.junit.Test;

public class PersonDaoTest
{
    @Test
    public void test()
    {
        Transaction transaction = new Transaction();
        PersonDao target = new PersonDaoImpl();
        //获得代理对象
        PersonDaoInteceptor inteceptor = new PersonDaoInteceptor(target, transaction);
        //调用目标方法
        PersonDaoImpl proxy = (PersonDaoImpl) inteceptor.createProxy();
        proxy.getPerson();
    }
}