public interface PersonDao {

 void savePerson();
}

public class PersonDaoImpl implements PersonDao {

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

public class Transaction {
 
 void beginTransaction(){
  System.out.println("begin Transaction");
 }
 
 void commit(){
  System.out.println("commit");
 }
}

/**
 * 靜態(tài)代理類
 * @author qjc
 */
public class PersonDaoProxy implements PersonDao{

 PersonDao personDao;
 Transaction transaction;
 
 public PersonDaoProxy(PersonDao personDao, Transaction transaction) {
  this.personDao = personDao;
  this.transaction = transaction;
 }

 @Override
 public void savePerson() {
  this.transaction.beginTransaction();
  this.personDao.savePerson();
  this.transaction.commit();
 }
}

/**
 * 測試靜態(tài)代理
 * @author qjc
 */
public class TestPersonProxy {
 
 @Test
 public void testSave(){
  PersonDao personDao = new PersonDaoImpl();
  Transaction transaction = new Transaction();
  PersonDaoProxy proxy = new PersonDaoProxy(personDao, transaction);
  
  proxy.savePerson();
 }
}

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

/**
 * 攔截器 
 *   1、目標(biāo)類導(dǎo)入進(jìn)來 
 *   2、事物導(dǎo)入進(jìn)來 
 *   3、invoke完成：開啟事務(wù)、調(diào)用目標(biāo)對(duì)象的方法、事務(wù)提交
 * 
 * @author qjc
 */
public class Interceptor implements InvocationHandler {

 private Object target; // 目標(biāo)類
 private Transaction transaction;

 public Interceptor(Object target, Transaction transaction) {
  this.target = target;
  this.transaction = transaction;
 }

 /**
  * @param proxy 目標(biāo)對(duì)象的代理類實(shí)例
  * @param method 對(duì)應(yīng)于在代理實(shí)例上調(diào)用接口方法的Method實(shí)例
  * @param args 傳入到代理實(shí)例上方法參數(shù)值的對(duì)象數(shù)組
  * @return 方法的返回值，沒有返回值是null
  * @throws Throwable
  */
 public Object invoke(Object proxy, Method method, Object[] args)
   throws Throwable {
  String methodName = method.getName();
  if ("savePerson".equals(methodName)
    || "deletePerson".equals(methodName)
    || "updatePerson".equals(methodName)) {

   this.transaction.beginTransaction(); // 開啟事務(wù)
   method.invoke(target); // 調(diào)用目標(biāo)方法
   this.transaction.commit(); // 提交事務(wù)

  } else {
   method.invoke(target);
  }
  return null;
 }
}

/**
 * 測試jdk動(dòng)態(tài)代理
 * @author qjc
 */
public class TestJDKProxy {
 
 @Test
 public void testSave(){
  /**
   * 1、創(chuàng)建一個(gè)目標(biāo)對(duì)象
   * 2、創(chuàng)建一個(gè)事務(wù)
   * 3、創(chuàng)建一個(gè)攔截器
   * 4、動(dòng)態(tài)產(chǎn)生一個(gè)代理對(duì)象
   */
  Object target = new PersonDaoImpl();
  Transaction transaction = new Transaction();
  Interceptor interceptor = new Interceptor(target, transaction);
  /**
   * 參數(shù)一：設(shè)置代碼使用的類加載器，一般采用跟目標(biāo)類相同的類加載器
   * 參數(shù)二：設(shè)置代理類實(shí)現(xiàn)的接口，跟目標(biāo)類使用相同的接口
   * 參數(shù)三：設(shè)置回調(diào)對(duì)象，當(dāng)代理對(duì)象的方法被調(diào)用時(shí)，會(huì)調(diào)用該參數(shù)指定對(duì)象的invoke方法
   */
  PersonDao personDao = (PersonDao) Proxy.newProxyInstance(
    target.getClass().getClassLoader(),
    target.getClass().getInterfaces(),
    interceptor);
  personDao.savePerson();
 }
}

import net.sf.cglib.proxy.Enhancer;
import net.sf.cglib.proxy.MethodInterceptor;
import net.sf.cglib.proxy.MethodProxy;

/**
 * CGLIB代理 攔截器 
 * @author qjc
 */
public class Interceptor implements MethodInterceptor {

 private Object target; // 代理的目標(biāo)類
 private Transaction transaction;

 public Interceptor(Object target, Transaction transaction) {
  this.target = target;
  this.transaction = transaction;
 }

 /**
  * 創(chuàng)建目標(biāo)對(duì)象的代理對(duì)象
  * 
  * @return
  */
 public Object createProxy() {
  // 代碼增強(qiáng)
  Enhancer enhancer = new Enhancer(); // 該類用于生成代理對(duì)象
  enhancer.setCallback(this); // 參數(shù)為攔截器
  enhancer.setSuperclass(target.getClass());// 設(shè)置父類
  return enhancer.create(); // 創(chuàng)建代理對(duì)象
 }

 /**
  * @param obj 目標(biāo)對(duì)象代理類的實(shí)例
  * @param method 代理實(shí)例上 調(diào)用父類方法的Method實(shí)例
  * @param args 傳入到代理實(shí)例上方法參數(shù)值的對(duì)象數(shù)組
  * @param methodProxy 使用它調(diào)用父類的方法
  * @return
  * @throws Throwable
  */
 public Object intercept(Object obj, Method method, Object[] args,
   MethodProxy methodProxy) throws Throwable {
  this.transaction.beginTransaction();
  method.invoke(target);
  this.transaction.commit();
  return null;
 }
}

/**
 * 測試cglib動(dòng)態(tài)代理
 * 通過cglib產(chǎn)生的代理對(duì)象，代理類是目標(biāo)類的子類
 * @author qjc
 */
public class TestCglibProxy {
 
 @Test
 public void testSave(){
 
  Object target = new PersonDaoImpl();
  Transaction transaction = new Transaction();
  Interceptor interceptor = new Interceptor(target, transaction);
  
  PersonDaoImpl personDaoImpl = (PersonDaoImpl) interceptor.createProxy();
  personDaoImpl.savePerson();
 }
}

 <bean id="personDao" class="cn.qjc.aop.xml.PersonDaoImpl"></bean>
 <bean id="transaction" class="cn.qjc.aop.xml.Transaction"></bean>
 
 <aop:config>
  <!-- 切入點(diǎn)表達(dá)式 確定目標(biāo)類 -->
  <aop:pointcut expression="execution(* cn.qjc.aop.xml.PersonDaoImpl.*(..))" id="perform"/>
 
  <!-- ref指向?qū)ο缶褪乔忻?-->
  <aop:aspect ref="transaction">
   <aop:before method="beginTransaction" pointcut-ref="perform"/>
   <aop:after-returning method="commit" pointcut-ref="perform"/>
  </aop:aspect>
 </aop:config>
 
</beans>

/**
 * 測試spring動(dòng)態(tài)代理
 * @author qjc
 */
public class TransactionTest {

 @Test
 public void testSave(){
  ApplicationContext context = new ClassPathXmlApplicationContext("cn/qjc/aop/xml/applicationContext.xml");
  PersonDao personDao = (PersonDao) context.getBean("personDao");
  personDao.savePerson();
 }
}