在使用的時候，遇到了部分的異常，我用的是最新的Spring版本，Spring-4.2.5版本的，首先確保你的配置文件中引入了下面紅色部分。
xmlns:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd">
1. aspectjrt.jar
2.aspectjweaver.jar
3.aopalliance-1.0.jar
我在使用的時候由於沒有使用第三個jar包導致了異常信息如下：
警告: Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.aop.config.internalAutoProxyCreator': Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.aop.aspectj.annotation.AnnotationAwareAspectJAutoProxyCreator]: Constructor threw exception; nested exception is java.lang.NoClassDefFoundError: org/aopalliance/intercept/MethodInterceptor Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.aop.config.internalAutoProxyCreator': Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.aop.aspectj.annotation.AnnotationAwareAspectJAutoProxyCreator]: Constructor threw exception; nested exception is java.lang.NoClassDefFoundError: org/aopalliance/intercept/MethodInterceptor at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1105) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1050) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:510) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) at org.springframework.context.support.PostProcessorRegistrationDelegate.registerBeanPostProcessors(PostProcessorRegistrationDelegate.java:228) at org.springframework.context.support.AbstractApplicationContext.registerBeanPostProcessors(AbstractApplicationContext.java:687) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:523) at org.springframework.context.support.ClassPathXmlApplicationContext.(ClassPathXmlApplicationContext.java:139) at org.springframework.context.support.ClassPathXmlApplicationContext. (ClassPathXmlApplicationContext.java:83) at com.siti.spring20160315aop.MainTest.main(MainTest.java:9) Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.aop.aspectj.annotation.AnnotationAwareAspectJAutoProxyCreator]: Constructor threw exception; nested exception is java.lang.NoClassDefFoundError: org/aopalliance/intercept/MethodInterceptor at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:163) at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:89) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1098) ... 13 more
下面開始使用AspectJ進行切面配置
定義四個接口，下面讓WangYang類實現這個Person的接口，並實現其中的方法。
package com.siti.spring20160315aop;
public interface Person {
void say();
void sayName(String name);
String saySth(String name);
void sayEx();
}
其中saySth這個方法設置了返回值，這個地方會被AfterReturning織入，然後sayEx方法為了測試故意利用空指針異常，測試AfterThrowing會不會被織入。
package com.siti.spring20160315aop;
public class WangYang implements Person{
@Override
public void say() {
System.out.println("wy!");
}
@Override
public void sayName(String name) {
System.out.println("name-->" + name);
}
@Override
public String saySth(String name) {
System.out.println("name-->" + name);
return name;
}
@Override
public void sayEx() {
Object obj = null;
obj.equals("1");
}
}
面向切面編程AspectJ的實現，主要方式如下，其中，after通知主要用於釋放資源，afterReturning通知可以對返回值進行更改，afterThrowing通知可以進行異常捕獲生成異常記錄，before這個通知可以進行參數的校驗之類的。
package com.siti.spring20160315aop;
import java.util.Arrays;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.AfterReturning;
import org.aspectj.lang.annotation.AfterThrowing;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
@Aspect
public class MyInterceptor {
@Pointcut("execution(* com.siti.spring20160315aop.WangYang.*(..))")
public void anyMethod(){}
@Before("anyMethod()")
public void checkMessage(JoinPoint joinPoint){
System.out.println("@Before-check!!!");
System.out.println("@Before-目標對象為：" + joinPoint.getTarget());
System.out.println("@Before-目標方法：" + joinPoint.getSignature().getName());
System.out.println("@Before-目標方法的參數：" + Arrays.toString(joinPoint.getArgs()));
}
@AfterReturning(pointcut = "anyMethod()", returning = "obj")
public void checkReturn(JoinPoint joinPoint, Object obj){
System.out.println("@AfterReturning-目標方法返回值：" + obj);
System.out.println("@AfterReturning-生成日志");
System.out.println("@AfterReturning-目標對象為：" + joinPoint.getTarget());
System.out.println("@AfterReturning-目標方法：" + joinPoint.getSignature().getName());
System.out.println("@AfterReturning-目標方法的參數：" + Arrays.toString(joinPoint.getArgs()));
}
@After("anyMethod()")
public void checkAfter(JoinPoint joinPoint){
System.out.println("@After-釋放資源！");
System.out.println("@After-目標對象為：" + joinPoint.getTarget());
System.out.println("@After-目標方法：" + joinPoint.getSignature().getName());
System.out.println("@After-目標方法的參數：" + Arrays.toString(joinPoint.getArgs()));
}
@Around("anyMethod()")
public Object checkAround(ProceedingJoinPoint joinPoint) throws Throwable{
System.out.println("@Around！");
Object[] args = joinPoint.getArgs();
if(args != null && args.length > 0 && args[0].getClass() == String.class){
args[0] = "@Around" + args[0];
}
Object result = joinPoint.proceed(args);
if(result != null && result.getClass() == String.class){
result = result + "--wy";
}
return result;
}
@AfterThrowing(throwing = "ex", pointcut = "anyMethod()")
public void checkAfterThrowing(Throwable ex){
System.out.println("@AfterThrowing-異常拋出！");
System.out.println("@AfterThrowing-異常日志！");
}
}
配置文件需要將我們自己寫的這個切面的類，在配置文件中進行“注冊”。
測試：
package com.siti.spring20160315aop;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class MainTest {
public static void main(String[] args) {
ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext20160315.xml");
Person wy = context.getBean("wy", Person.class);
wy.say();
wy.sayName("wangyang-");
String str = wy.saySth("hello--");
System.out.println("str的值：" + str);
// wy.sayEx();// 拋出異常的測試
}
}
基於配置文件配置的方式和前面的注解的方式基本上類似的，這裡只是將，改動的地方列出來，不做介紹了。
配置文件如下：
package com.siti.spring20160315aopwithxml;
import java.util.Arrays;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
public class MyInterceptor {
public void anyMethod(){}
public void checkMessage(JoinPoint joinPoint){
System.out.println("@Before-check!!!");
System.out.println("@Before-目標對象為：" + joinPoint.getTarget());
System.out.println("@Before-目標方法：" + joinPoint.getSignature().getName());
System.out.println("@Before-目標方法的參數：" + Arrays.toString(joinPoint.getArgs()));
}
public void checkReturn(JoinPoint joinPoint, Object obj){
System.out.println("@AfterReturning-目標方法返回值：" + obj);
System.out.println("@AfterReturning-生成日志");
System.out.println("@AfterReturning-目標對象為：" + joinPoint.getTarget());
System.out.println("@AfterReturning-目標方法：" + joinPoint.getSignature().getName());
System.out.println("@AfterReturning-目標方法的參數：" + Arrays.toString(joinPoint.getArgs()));
}
public void checkAfter(JoinPoint joinPoint){
System.out.println("@After-釋放資源！");
System.out.println("@After-目標對象為：" + joinPoint.getTarget());
System.out.println("@After-目標方法：" + joinPoint.getSignature().getName());
System.out.println("@After-目標方法的參數：" + Arrays.toString(joinPoint.getArgs()));
}
public Object checkAround(ProceedingJoinPoint joinPoint) throws Throwable{
System.out.println("@Around！");
Object[] args = joinPoint.getArgs();
if(args != null && args.length > 0 && args[0].getClass() == String.class){
args[0] = "@Around" + args[0];
}
Object result = joinPoint.proceed(args);
if(result != null && result.getClass() == String.class){
result = result + "--wy";
}
return result;
}
public void checkAfterThrowing(Throwable ex){
System.out.println("@AfterThrowing-異常拋出！");
System.out.println("@AfterThrowing-異常日志！");
}
}
