`

spring aop

阅读更多
理解spring aop的路径:最初级的做法是通过使用代理将业务代码和系统代码分离,也就是在向代理类中注入业务接口实现类,然后在调用业务接口代码时调用系统代码; 
Java代码 
//******* TimeBook.java**************   
import org.apache.log4j.Level;   
import org.apache.log4j.Logger;   
public class TimeBook {   
         private Logger logger = Logger.getLogger(this.getClass().getName());    
         //审核数据的相关程序   
         public void doAuditing(String name) {    
                  logger.log(Level.INFO, name + " 开始审核数据....");    
                  //审核数据的相关程序   
                  ……       
                  logger.log(Level.INFO, name + " 审核数据结束....");    
         }   
}   
//******* TestHelloWorld.java**************   
package com.gc.test;   
import com.gc.action.TimeBook;   
public class TestHelloWorld {   
         public static void main(String[] args) {    
                   TimeBook timeBook = new TimeBook();   
                   timeBook.doAuditing("张三");   
    }    
}   
//******* TimeBookInterface.java**************   
package com.gc.impl;   
import org.apache.log4j.Level;   
//通过面向接口编程实现日志输出   
public interface TimeBookInterface    
{   
         public void doAuditing(String name);   
}   
//******* TimeBook.java**************   
package com.gc.action;   
import com.gc.impl.TimeBookInterface;   
public class TimeBook implements TimeBookInterface    
{   
public void doAuditing(String name) {    
//审核数据的相关程序   
……       
}   
}   
//******* TimeBookProxy.java**************   
package com.gc.action;   
import org.apache.log4j.Level;   
import org.apache.log4j.Logger;   
import com.gc.impl.TimeBookInterface;   
public class TimeBookProxy    
{   
   private Logger logger = Logger.getLogger(this.getClass().getName());    
   private TimeBookInterface timeBookInterface;    
   //在该类中针对前面的接口TimeBookInterface编程,而不针对具体的类   
     public TimeBookProxy(TimeBookInterface timeBookInterface)    
     {    
         this.timeBookInterface = timeBookInterface;    
     }   
          //实际业务处理   
          public void doAuditing(String name)    
           {    
                   logger.log(Level.INFO, name + " 开始审核数据....");    
                   timeBookInterface.doAuditing(name);    //调用方法   
                   logger.log(Level.INFO, name + " 审核数据结束....");    
          }   
}   
//******* TestHelloWorld.java**************   
package com.gc.test;   
import com.gc.action.TimeBook;   
import com.gc.action.TimeBookProxy;   
public class TestHelloWorld {   
         public static void main(String[ ] args)    
             {    
                     //这里针对接口进行编程   
                     TimeBookProxy timeBookProxy  = new TimeBookProxy(new TimeBook());   
                     timeBookProxy .doAuditing("张三");   
             }    
}  

//******* TimeBook.java**************
import org.apache.log4j.Level;
import org.apache.log4j.Logger;
public class TimeBook {
         private Logger logger = Logger.getLogger(this.getClass().getName()); 
         //审核数据的相关程序
         public void doAuditing(String name) { 
                  logger.log(Level.INFO, name + " 开始审核数据...."); 
                  //审核数据的相关程序
                  ……    
                  logger.log(Level.INFO, name + " 审核数据结束...."); 
         }
}
//******* TestHelloWorld.java**************
package com.gc.test;
import com.gc.action.TimeBook;
public class TestHelloWorld {
         public static void main(String[] args) { 
                   TimeBook timeBook = new TimeBook();
                   timeBook.doAuditing("张三");
    } 
}
//******* TimeBookInterface.java**************
package com.gc.impl;
import org.apache.log4j.Level;
//通过面向接口编程实现日志输出
public interface TimeBookInterface 
{
         public void doAuditing(String name);
}
//******* TimeBook.java**************
package com.gc.action;
import com.gc.impl.TimeBookInterface;
public class TimeBook implements TimeBookInterface 
{
public void doAuditing(String name) { 
//审核数据的相关程序
……    
}
}
//******* TimeBookProxy.java**************
package com.gc.action;
import org.apache.log4j.Level;
import org.apache.log4j.Logger;
import com.gc.impl.TimeBookInterface;
public class TimeBookProxy 
{
   private Logger logger = Logger.getLogger(this.getClass().getName()); 
   private TimeBookInterface timeBookInterface; 
   //在该类中针对前面的接口TimeBookInterface编程,而不针对具体的类
     public TimeBookProxy(TimeBookInterface timeBookInterface) 
     { 
         this.timeBookInterface = timeBookInterface; 
     }
          //实际业务处理
          public void doAuditing(String name) 
           { 
                   logger.log(Level.INFO, name + " 开始审核数据...."); 
                   timeBookInterface.doAuditing(name);    //调用方法
                   logger.log(Level.INFO, name + " 审核数据结束...."); 
          }
}
//******* TestHelloWorld.java**************
package com.gc.test;
import com.gc.action.TimeBook;
import com.gc.action.TimeBookProxy;
public class TestHelloWorld {
         public static void main(String[ ] args) 
             { 
                     //这里针对接口进行编程
                     TimeBookProxy timeBookProxy  = new TimeBookProxy(new TimeBook());
                     timeBookProxy .doAuditing("张三");
             } 
}
为了更加通用, 引入java的动态代理机制来解除代理类注入的业务类必须实现指定接口的限制, 这个要将前面所说的代理类进行修改,让其实现InvocationHandler 接口, 该接口有两个方法:bind and invoke methods;在bind方法中和前面一样用来注入业务类(只不过该业务类不在是特定的类, 而是一个Object对象), 在invoke中将业务逻辑调用代码和系统代码进行混合(其中也使用了反射机制); 
Java代码 
//******* LogProxy.java**************   
package com.gc.action;   
import java.lang.reflect.InvocationHandler;   
import java.lang.reflect.Method;   
import java.lang.reflect.Proxy;   
import org.apache.log4j.Level;   
import org.apache.log4j.Logger;   
//代理类实现了接口InvocationHandler   
public class LogProxy implements InvocationHandler    
{   
         private Logger logger = Logger.getLogger(this.getClass().getName());    
         private Object delegate;    
         //绑定代理对象    
         public Object bind(Object delegate)    
             {    
                     this.delegate = delegate;    
                     return Proxy.newProxyInstance(delegate.getClass().getClassLoader(),    
                     delegate.getClass().   
                     getInterfaces(), this);    
             }    
        //针对接口编程    
         public Object invoke(Object proxy, Method method, Object[ ] args) throws Throwable    
             {    
                     Object result = null;    
                              try {    
                                         //在方法调用前后进行日志输出   
                                        logger.log(Level.INFO, args[0] + " 开始审核数据....");    
                                        result = method.invoke(delegate, args); //调用绑定对象的方法   
                                        logger.log(Level.INFO, args[0] + " 审核数据结束....");   
                                  }    
                            catch (Exception e)   
                                 {    
                                       logger.log(Level.INFO, e.toString());    
                                 }    
                      return result;    
           }    
}   
//******* TestHelloWorld.java**************   
package com.gc.test;   
import com.gc.action.TimeBook;   
import com.gc.action.TimeBookProxy;   
import com.gc.impl.TimeBookInterface;   
import com.gc.action.LogProxy;   
public class TestHelloWorld {   
         public static void main(String[ ] args)    
                {    
                      //实现了对日志类的重用   
                      LogProxy logProxy  = new LogProxy();    
                      TimeBookInterface timeBookProxy = (TimeBookInterface)logProxy.bind(new TimeBook());    
                      timeBookProxy.doAuditing("张三");   
                }    
}  

//******* LogProxy.java**************
package com.gc.action;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import org.apache.log4j.Level;
import org.apache.log4j.Logger;
//代理类实现了接口InvocationHandler
public class LogProxy implements InvocationHandler 
{
         private Logger logger = Logger.getLogger(this.getClass().getName()); 
         private Object delegate; 
         //绑定代理对象 
         public Object bind(Object delegate) 
             { 
                     this.delegate = delegate; 
                     return Proxy.newProxyInstance(delegate.getClass().getClassLoader(), 
                     delegate.getClass().
                     getInterfaces(), this); 
             } 
        //针对接口编程 
         public Object invoke(Object proxy, Method method, Object[ ] args) throws Throwable 
             { 
                     Object result = null; 
                              try { 
                                         //在方法调用前后进行日志输出
                                        logger.log(Level.INFO, args[0] + " 开始审核数据...."); 
                                        result = method.invoke(delegate, args); //调用绑定对象的方法
                                        logger.log(Level.INFO, args[0] + " 审核数据结束....");
                                  } 
                            catch (Exception e)
                                 { 
                                       logger.log(Level.INFO, e.toString()); 
                                 } 
                      return result; 
           } 
}
//******* TestHelloWorld.java**************
package com.gc.test;
import com.gc.action.TimeBook;
import com.gc.action.TimeBookProxy;
import com.gc.impl.TimeBookInterface;
import com.gc.action.LogProxy;
public class TestHelloWorld {
         public static void main(String[ ] args) 
                { 
                      //实现了对日志类的重用
                      LogProxy logProxy  = new LogProxy(); 
                      TimeBookInterface timeBookProxy = (TimeBookInterface)logProxy.bind(new TimeBook()); 
                      timeBookProxy.doAuditing("张三");
                } 
}

spring 的aop实现正是建立在java的动态代理机制上。要理解aop还必须理解几个概念, 第一个就是PointCut(切入点),可以将其理解为所有要进行代理的业务对象及其方法的集合(也可以理解为JoinPoint的集合,说穿了就是注入业务代码的位置, 而这个位置就是JoinPoint), 这一点可以从Spring AOP的PointCut接口定义中看出来: 
Java代码 
package org.springframework.aop;   
public interface Pointcut    
{   
         //用来将切入点限定在给定的目标类中   
         ClassFilter getClassFilter();   
         //用来判断切入点是否匹配目标类给定的方法   
         MethodMatcher getMethodMatcher();   
         Pointcut TRUE = TruePointcut.INSTANCE;   
}  

package org.springframework.aop;
public interface Pointcut 
{
         //用来将切入点限定在给定的目标类中
         ClassFilter getClassFilter();
         //用来判断切入点是否匹配目标类给定的方法
         MethodMatcher getMethodMatcher();
         Pointcut TRUE = TruePointcut.INSTANCE;
}

跟PointCut对应的是JoinPoint(连接点),也就是插入系统代码的方法调用、异常抛出等 
最后一个概念就是通知(Advice)也就是用来放系统代码的地方, 而Advisor = Advise+PointCut(这里是指的具体的位置,比如指定的方法名) 
常用的Advisor是org.springframework.aop.support.RegexpMethodPointcutAdvisor 
这个需要理解正则表达式的一些概念: 

引用

(1)“.”,可以用来匹配任何一个字符。比如:正则表达式为“g.f”,它就会匹配“gaf”、“g1f”、“g*f”和“g #f”等。 
(2)“[]”,只有[]里指定的字符才能匹配。比如:正则表达式为“g[abc]f”,它就只能匹配“gaf”、“gbf”和“gcf”,而不会匹配“g1f”、“g*f”和“g#f”等。 
(3)“*”,表示匹配次数,可以任意次,用来确定紧靠该符号左边的符号出现的次数。比如:正则表达式为“g.*f”,它能匹配“gaf”、“gaaf”、“gf”和“g*f”等。 
(4)“?”,可以匹配0或1次,用来确定紧靠该符号左边的符号出现的次数。比如:正则表达式为“g.?f”,它能匹配“gaf”“g*f”等。 
(5)“\”,是正则表达式的连接符。比如:正则表达式为“g.\-f”,它能匹配“g-f”、“ga-f”和“g*-f”等。 


Xml代码 
<?xml version="1.0" encoding="UTF-8"?>  
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN"   
"http://www.springframework.org/dtd/spring-beans.dtd">  
<beans>  
<bean id="log" class="com.gc.action.LogAround"/>  
<bean id="timeBook" class="com.gc.action.TimeBook"/>  
<!--代理目标类的指定方法-->  
<bean id="logAdvisor"class="org.springframework.aop.support.RegexpMethodPointcutAdvisor">    
        <property name="advice">    
            <ref bean="log"/>    
        </property>    
               <!--指定要代理的方法-->  
        <property name="patterns">    
            <value>.*doAuditing.* </value>    
        </property>    
    </bean>  
<!--设定代理类-->  
<bean id="logProxy" class="org.springframework.aop.framework.ProxyFactoryBean">    
        <property name="proxyInterfaces">    
            <value>com.gc.impl.TimeBookInterface</value>  
        </property>  
        <property name="target">  
            <ref bean="timeBook"/>  
        </property>  
        <property name="interceptorNames">  
            <list>  
                <value>logAdvisor</value>  
            </list>  
        </property>  
    </bean>  
</beans>  

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN"
"http://www.springframework.org/dtd/spring-beans.dtd">
<beans>
<bean id="log" class="com.gc.action.LogAround"/>
<bean id="timeBook" class="com.gc.action.TimeBook"/>
<!--代理目标类的指定方法-->
<bean id="logAdvisor"class="org.springframework.aop.support.RegexpMethodPointcutAdvisor"> 
        <property name="advice"> 
            <ref bean="log"/> 
        </property> 
               <!--指定要代理的方法-->
        <property name="patterns"> 
            <value>.*doAuditing.* </value> 
        </property> 
    </bean>
<!--设定代理类-->
<bean id="logProxy" class="org.springframework.aop.framework.ProxyFactoryBean"> 
        <property name="proxyInterfaces"> 
            <value>com.gc.impl.TimeBookInterface</value>
        </property>
        <property name="target">
            <ref bean="timeBook"/>
        </property>
        <property name="interceptorNames">
            <list>
                <value>logAdvisor</value>
            </list>
        </property>
    </bean>
</beans>


spring提供了四种Advice: 
第1种:在需要调用方面的方法前后都调用处理方面的代码 
第2种:在需要调用方面的方法之前调用处理方面的代码 
第3种:在需要调用方面的方法之后都调用处理方面的代码 
第4种:在需要调用方面的方法发生异常时调用处理方面的代码 
示例配置代码如下 
Xml代码 
<?xml version="1.0" encoding="UTF-8"?>  
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN"   
 "http://www.springframework.org/dtd/spring-beans.dtd">  
<beans>  
<bean id="log" class="com.gc.action.LogAop"/>  
<bean id="timeBook" class="com.gc.action. timeBook "/>  
<bean id=”logProxy” class=”org.springframework.aop.framework.ProxyFactor   
yBean”>  
    <property name=”proxyInterfaces”>  
        <value>com.gc.impl.TimeBookInterface</value>  
    </property>  
    <property name=”target”>  
        <ref bean=”timeBook”/>  
    </property>  
    <property name=”interceptorNames”>  
         <list>  
              <value>log</value>  
         </list>  
    </property>  
</bean>  
</beans>  

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN"
 "http://www.springframework.org/dtd/spring-beans.dtd">
<beans>
<bean id="log" class="com.gc.action.LogAop"/>
<bean id="timeBook" class="com.gc.action. timeBook "/>
<bean id=”logProxy” class=”org.springframework.aop.framework.ProxyFactor
yBean”>
    <property name=”proxyInterfaces”>
        <value>com.gc.impl.TimeBookInterface</value>
    </property>
    <property name=”target”>
        <ref bean=”timeBook”/>
    </property>
    <property name=”interceptorNames”>
         <list>
              <value>log</value>
         </list>
    </property>
</bean>
</beans>
所有的配置都一样, 只是Advice不同而已: 
Java代码 
import org.aopalliance.intercept.MethodInterceptor;   
import org.aopalliance.intercept.MethodInvocation;   
import org.apache.log4j.Level;   
import org.apache.log4j.Logger;   
    
public class LogAround implements MethodInterceptor{   
      private Logger logger = Logger.getLogger(this.getClass().getName());    
       
    public Object invoke(MethodInvocation methodInvocation) throws Throwable {    
           logger.log(Level.INFO, methodInvocation.getArguments()[0] + " 开始审核数据....");    
        try {    
          Object result = methodInvocation.proceed();    
          return result;    
        }    
        finally {    
                 logger.log(Level.INFO, methodInvocation.getArguments()[0] + " 审核数据结束....");   
        }           
   }    
}        
  
import java.lang.reflect.Method;   
    
import org.apache.log4j.Level;   
import org.apache.log4j.Logger;   
import org.springframework.aop.MethodBeforeAdvice;   
    
public class LogBefore implements MethodBeforeAdvice {   
       private Logger logger = Logger.getLogger(this.getClass().getName());    
       
    public void before(Method method, Object[] args, Object target) throws Throwable {    
              logger.log(Level.INFO, args[0] + " 开始审核数据....");   
   }   
}   
  
import java.lang.reflect.Method;   
    
import org.apache.log4j.Level;   
import org.apache.log4j.Logger;   
import org.springframework.aop.AfterReturningAdvice;   
    
public class LogAfterReturning implements AfterReturningAdvice {   
       private Logger logger = Logger.getLogger(this.getClass().getName());    
       
    public void afterReturning(Method method, Object[] args, Object target) throws Throwable {    
              logger.log(Level.INFO, args[0] + " 开始审核数据....");   
   }   
}   
  
import java.lang.reflect.Method;   
    
import org.apache.log4j.Level;   
import org.apache.log4j.Logger;   
import org.springframework.aop.ThrowsAdvice;   
    
public class LogThrow implements ThrowsAdvice {   
       private Logger logger = Logger.getLogger(this.getClass().getName());    
       
    public void afterThrowing(Method method, Object[] args, Object target,Throwable subclass) throws Throwable {    
              logger.log(Level.INFO, args[0] + " 开始审核数据....");   
   }   
}  

import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;
import org.apache.log4j.Level;
import org.apache.log4j.Logger;
 
public class LogAround implements MethodInterceptor{
      private Logger logger = Logger.getLogger(this.getClass().getName()); 
    
    public Object invoke(MethodInvocation methodInvocation) throws Throwable { 
           logger.log(Level.INFO, methodInvocation.getArguments()[0] + " 开始审核数据...."); 
        try { 
          Object result = methodInvocation.proceed(); 
          return result; 
        } 
        finally { 
                 logger.log(Level.INFO, methodInvocation.getArguments()[0] + " 审核数据结束....");
        }        
   } 
}     

import java.lang.reflect.Method;
 
import org.apache.log4j.Level;
import org.apache.log4j.Logger;
import org.springframework.aop.MethodBeforeAdvice;
 
public class LogBefore implements MethodBeforeAdvice {
       private Logger logger = Logger.getLogger(this.getClass().getName()); 
    
    public void before(Method method, Object[] args, Object target) throws Throwable { 
              logger.log(Level.INFO, args[0] + " 开始审核数据....");
   }
}

import java.lang.reflect.Method;
 
import org.apache.log4j.Level;
import org.apache.log4j.Logger;
import org.springframework.aop.AfterReturningAdvice;
 
public class LogAfterReturning implements AfterReturningAdvice {
       private Logger logger = Logger.getLogger(this.getClass().getName()); 
    
    public void afterReturning(Method method, Object[] args, Object target) throws Throwable { 
              logger.log(Level.INFO, args[0] + " 开始审核数据....");
   }
}

import java.lang.reflect.Method;
 
import org.apache.log4j.Level;
import org.apache.log4j.Logger;
import org.springframework.aop.ThrowsAdvice;
 
public class LogThrow implements ThrowsAdvice {
       private Logger logger = Logger.getLogger(this.getClass().getName()); 
    
    public void afterThrowing(Method method, Object[] args, Object target,Throwable subclass) throws Throwable { 
              logger.log(Level.INFO, args[0] + " 开始审核数据....");
   }
}

除了使用ProxyFactoryBean来创建AOP代理外,还可以使用DefaultAdvisorAutoProxyCreator来创建自动代理, 当在配置文件中包括DefaultAdvisorAutoProxyCreator bean定义,那么在Bean定义档被读取完之后, DefaultAdvisorAutoProxyCreator会自动搜寻所有的Advisor(因为DefaultAdvisorAutoProxyCreator实现了BeanProcessor接口),并自动将Advisor应用至符合Pointcut的目标业务类上。实际上这是一个偷懒的做法, 将advisor和具体业务类的关联管理处理交给spring去处理了。 

在指定业务对象的同时还需要指定业务对象所实现的接口(面向接口编程), 如果业务对象没有实现接口就需要借助cglib(这个一般是针对那些不能修改源代码的遗留系统的做法),对应的配置文件应该这样写: 
Xml代码 
<?xml version="1.0" encoding="UTF-8"?>  
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN"   
 "http://www.springframework.org/dtd/spring-beans.dtd">  
<beans>  
<bean id="log" class="com.gc.action.LogAop"/>  
<bean id="timeBook" class="com.gc.action. timeBook "/>  
<bean id=”logProxy” class=”org.springframework.aop.framework.ProxyFactor   
yBean”>  
//增加如下属性,就表示使用的是CGLIB代理(对目标类直接代理)   
    <property name=”proxyTargetClass”>  
        <value>true</value>  
    </property>  
   /*然后去掉下面的属性,也就是说此种方法不需要面向接口,或不需要指出接口    
<property name=”proxyInterfaces”>  
        <value>com.gc.impl.TimeBookInterface</value>  
    </property>*/   
    <property name=”target”>  
        <ref bean=”timeBook”/>  
    </property>  
    <property name=”interceptorNames”>  
         <list>  
              <value>log</value>  
         </list>  
    </property>  
</bean>  
</beans>  

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN"
 "http://www.springframework.org/dtd/spring-beans.dtd">
<beans>
<bean id="log" class="com.gc.action.LogAop"/>
<bean id="timeBook" class="com.gc.action. timeBook "/>
<bean id=”logProxy” class=”org.springframework.aop.framework.ProxyFactor
yBean”>
//增加如下属性,就表示使用的是CGLIB代理(对目标类直接代理)
    <property name=”proxyTargetClass”>
        <value>true</value>
    </property>
   /*然后去掉下面的属性,也就是说此种方法不需要面向接口,或不需要指出接口 
<property name=”proxyInterfaces”>
        <value>com.gc.impl.TimeBookInterface</value>
    </property>*/
    <property name=”target”>
        <ref bean=”timeBook”/>
    </property>
    <property name=”interceptorNames”>
         <list>
              <value>log</value>
         </list>
    </property>
</bean>
</beans>

在spring2.0之后, 提供了基于schema的aop配置, 与以前的配置相比,它对spring的一些aop实现细节做了进一步的屏蔽(比如代理和拦截器),对spring aop的使用者来说更简单了。 

基于schema的aop借用了一些AspectJ中的一些做法, 如果对AspectJ比较熟悉的话, 使用起来是非常容易的。 
首先对里面的一些aop元素进行一下说明: 
aop:config是aop配置中的一个顶级元素, 所有的aop的配置定义都必须包含在该元素中 

aop:aspect类似于以前spring2.0以前配置中那个Advisor(但是又不完全是,因为还有一个aop:advisor元素与之对应),它包含了PointCut和Advice信息, 它会有一个对应的bean,许多advice信息也包含在里面,不过不用在象以前那样实现指定的BeforeXxx, AroundXxxx之类的接口了, 可以直接通过 org.aspectj.lang.ProceedingJoinPoint来调用指定切面对象的方法。 
比如: 
Xml代码 
<aop:aspect id="aroundExample" ref="aBean">  
    <aop:around  
      pointcut-ref="businessService"  
      method="doBasicProfiling"/>  
    ...   
</aop:aspect>  

<aop:aspect id="aroundExample" ref="aBean">
	<aop:around
	  pointcut-ref="businessService"
	  method="doBasicProfiling"/>
	...
</aop:aspect>

方法doBasicProfiling就是aBean中定义的一个方法, 它的定义是这样的: 
Java代码 
public Object doBasicProfiling(ProceedingJoinPoint pjp) throws Throwable {   
    // start stopwatch   
    Object retVal = pjp.proceed();   
    // stop stopwatch   
    return retVal;   
}  

public Object doBasicProfiling(ProceedingJoinPoint pjp) throws Throwable {
    // start stopwatch
    Object retVal = pjp.proceed();
    // stop stopwatch
    return retVal;
}

aop:pointcut 是切入点定义,跟以前的切入点定义没有什么区别,不过象以前那种正则表达式定义放到了expression属性中, 而且使用了AspectJ的语法。它可以定义在aop:aspect中, 也可以定义在aop:config中 

aop:after-returning(before, after-throwing, after, around)这个是Advice的定义, 它里面指定了要跟已定义的哪个切入点关联(pointcut-ref属性), 并且使用aspect中定义的哪个方法(method属性)。

 

分享到:
评论

相关推荐

Global site tag (gtag.js) - Google Analytics