Spring入门第二十三课

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我们看基于XML配置的方式配置AOP

看代码:

package logan.study.aop.impl;

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);
}
package logan.study.aop.impl;


public class ArithmeticCalculatorImpl implements ArithmeticCalculator {

    @Override
    public int add(int i, int j) {
        // TODO Auto-generated method stub
        int result = i + j;
        return result;
    }

    @Override
    public int sub(int i, int j) {
        // TODO Auto-generated method stub
        int result = i - j;
        return result;
    }

    @Override
    public int mul(int i, int j) {
        // TODO Auto-generated method stub
        int result = i * j;
        return result;
    }

    @Override
    public int div(int i, int j) {
        // TODO Auto-generated method stub
        int result = i / j;
        return result;
    }

}
package logan.study.aop.impl;

import java.util.Arrays;
import java.util.List;

import org.aspectj.lang.JoinPoint;


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 with "+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 with "+args);
    }
    
    
    public void afterReturningMethod(JoinPoint joinPoint,Object result){
        String methodName = joinPoint.getSignature().getName();
        System.out.println("The method "+ methodName +" ends with "+result);
    }
    
    
    public void afterThrowingMethod(JoinPoint joinPoint,Exception ex){
        String methodName = joinPoint.getSignature().getName();
        System.out.println("The method "+ methodName +" occus with "+ex);
    }

}
package logan.study.aop.impl;

import java.util.Arrays;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Before;
public class VlidationAspect {
    @Before("LoggingAspect.declareJoinPointException()")
    public void validateArgs(JoinPoint joinPoint){
        System.out.println("validate: " + Arrays.asList(joinPoint.getArgs()));
    }

}
<?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">

    <bean id="arithmeticCalculator"
    class="logan.study.aop.impl.ArithmeticCalculatorImpl"></bean>
    
    <bean id="loggingAspect"
    class="logan.study.aop.impl.LoggingAspect"></bean>
    
    <bean id="vlidationAspect"
    class="logan.study.aop.impl.VlidationAspect"></bean>
    
    <aop:config>
        <aop:pointcut expression="execution(* logan.study.aop.impl.ArithmeticCalculatorImpl.*(int, int))" 
        id="pointcut"/>
        <aop:aspect ref="loggingAspect" order="2">
            <aop:before method="beforeMethod" pointcut-ref="pointcut"/>
            <aop:after method="afterMethod" pointcut-ref="pointcut"/>
            <aop:after-returning method="afterReturningMethod" pointcut-ref="pointcut" returning="result"/>
            <aop:after-throwing method="afterThrowingMethod" pointcut-ref="pointcut" throwing="ex"/>
        </aop:aspect>
        <aop:aspect ref="vlidationAspect" order="1">
            <aop:before method="validateArgs" pointcut-ref="pointcut"/>
        </aop:aspect>
    </aop:config>

</beans>
package logan.study.aop.impl;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Main {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        //1.创建Spring的IOC容器
        ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext-xml.xml");
        //2.从IOC容器里面获取bean实例
        ArithmeticCalculator arithmeticCalculator = ctx.getBean(ArithmeticCalculator.class);
        //使用Bean
        int result = arithmeticCalculator.add(3, 6);
        System.out.println(result);
        
        result = arithmeticCalculator.div(3, 1);
        System.out.println(result);

    }

}

返回结果:

五月 28, 2017 7:53:29 上午 org.springframework.context.support.ClassPathXmlApplicationContext prepareRefresh
信息: Refreshing org[email protected]49c2faae: startup date [Sun May 28 07:53:29 CST 2017]; root of context hierarchy
五月 28, 2017 7:53:29 上午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [applicationContext-xml.xml]
validate: [3, 6]
The method add begins with [3, 6]
The method add ends with [3, 6]
The method add ends with 9
9
validate: [3, 1]
The method div begins with [3, 1]
The method div ends with [3, 1]
The method div ends with 3
3

稍微修改代码:

package logan.study.aop.impl;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Main {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        //1.创建Spring的IOC容器
        ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext-xml.xml");
        //2.从IOC容器里面获取bean实例
        ArithmeticCalculator arithmeticCalculator = ctx.getBean(ArithmeticCalculator.class);
        //使用Bean
        int result = arithmeticCalculator.add(3, 6);
        System.out.println(result);
        
        result = arithmeticCalculator.div(3, 0);
        System.out.println(result);

    }

}

返回结果:

五月 28, 2017 7:56:58 上午 org.springframework.context.support.ClassPathXmlApplicationContext prepareRefresh
信息: Refreshing org[email protected]49c2faae: startup date [Sun May 28 07:56:58 CST 2017]; root of context hierarchy
五月 28, 2017 7:56:58 上午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [applicationContext-xml.xml]
validate: [3, 6]
The method add begins with [3, 6]
The method add ends with [3, 6]
The method add ends with 9
9
validate: [3, 0]
The method div begins with [3, 0]
The method div ends with [3, 0]
The method div occus with java.lang.ArithmeticException: / by zero
Exception in thread "main" java.lang.ArithmeticException: / by zero
    at logan.study.aop.impl.ArithmeticCalculatorImpl.div(ArithmeticCalculatorImpl.java:30)
    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:498)
    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.framework.adapter.AfterReturningAdviceInterceptor.invoke(AfterReturningAdviceInterceptor.java:52)
    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.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:52)
    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 logan.study.aop.impl.Main.main(Main.java:18)

 

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