实现两个整数的加减乘除,在每个方法执行前后打印日志。
ArithmeticCalculator.java:
package spring.aop.impl.xml; public interface ArithmeticCalculator { int add(int i,int j); int sub(int i,int j); int mul(int i,int j); int div(int i,int j); }
ArithmeticCalculatorImpl.java:
package spring.aop.impl.xml; public class ArithmeticCalculatorImpl implements ArithmeticCalculator { public int add(int i, int j) { int result = i+j; return result; } public int sub(int i, int j) { int result = i-j; return result; } public int mul(int i, int j) { int result = i*j; return result; } public int div(int i, int j) { int result = i/j; return result; } }
LoggingAspect.java:
package spring.aop.impl.xml; import java.util.Arrays; import java.util.List; 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; import org.springframework.core.annotation.Order; import org.springframework.stereotype.Component; public class LoggingAspect { public void beforeMethod(JoinPoint joinPoint){ String methodName=joinPoint.getSignature().getName(); List<Object> args=Arrays.asList(joinPoint.getArgs()); System.out.println("The method "+methodName+" begins "+args); } public void afterMethod(JoinPoint joinPoint){ String methodName=joinPoint.getSignature().getName(); List<Object> args=Arrays.asList(joinPoint.getArgs()); System.out.println("The method "+methodName+" ends "); } public void afterReturnMethod(JoinPoint joinPoint,Object result){ String methodName=joinPoint.getSignature().getName(); System.out.println("The method "+methodName+" ends with afterReturning "+ result); } public void afterThrowing(JoinPoint joinPoint,Exception ex){ String methodName=joinPoint.getSignature().getName(); System.out.println("The method "+methodName+" occurs exection: "+ ex); } public Object aroundMethod(ProceedingJoinPoint joinPoint){ Object result=null; String methodName=joinPoint.getSignature().getName(); try { //前置通知 System.out.println("---->The method "+methodName+" begins with" +Arrays.asList(joinPoint.getArgs())); //执行目标方法 result=joinPoint.proceed(); //返回通知 System.out.println("---->"+result); } catch (Throwable e) { e.printStackTrace(); //异常通知 System.out.println("---->"+e); } //后置通知 System.out.println("---->The method "+methodName+ "ends"); return result; } }
ApplicationContext.xml:
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.3.xsd"> <!-- 配置bean --> <bean id="arithmeticCalculator" class="spring.aop.impl.xml.ArithmeticCalculatorImpl"> </bean> <!-- 配置切面的bean --> <bean id="loggingAspect" class="spring.aop.impl.xml.LoggingAspect"> </bean> <!-- 配置AOP --> <aop:config> <!-- 配置切点表达式 --> <aop:pointcut expression="execution(* spring.aop.impl.xml.ArithmeticCalculator.*(..))" id="pointcut"/> <!-- 配置切面及通知 --> <aop:aspect ref="loggingAspect" order="1"> <aop:before method="beforeMethod" pointcut-ref="pointcut"/> <aop:after method="afterMethod" pointcut-ref="pointcut"/> <aop:after-throwing method="afterThrowing" pointcut-ref="pointcut" throwing="ex"/> </aop:aspect> </aop:config> </beans>
测试:
package spring.aop.impl.xml.test; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import spring.aop.impl.xml.ArithmeticCalculator; public class Main { public static void main(String[] args) { ApplicationContext ctx=new ClassPathXmlApplicationContext("applicationContext-xml.xml"); ArithmeticCalculator arithmeticCalculator=(ArithmeticCalculator) ctx.getBean("arithmeticCalculator"); int result=arithmeticCalculator.add(10, 20); System.out.println("result:"+result); result=arithmeticCalculator.div(10, 0); System.out.println("result:"+result); } }
输出:
The method add begins [10, 20]
The method add ends
result:30
The method div begins [10, 0]
The method div ends
The method div occurs exection: java.lang.ArithmeticException: / by zero
Exception in thread "main" java.lang.ArithmeticException: / by zero
at spring.aop.impl.xml.ArithmeticCalculatorImpl.div(ArithmeticCalculatorImpl.java:22)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:333)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:190)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
at org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:52)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.aspectj.AspectJAfterAdvice.invoke(AspectJAfterAdvice.java:47)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.aspectj.AspectJAfterThrowingAdvice.invoke(AspectJAfterThrowingAdvice.java:62)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:213)
at com.sun.proxy.$Proxy2.div(Unknown Source)
at spring.aop.impl.xml.test.Main.main(Main.java:19)