Spring AOP - After Advice

After Advice (After Returning Advice)

• Both (After Advice and After Returning Advice) are almost same and similar to before advice; only difference is that these services are applied after completion of our business logic.

• We should implement AfterReturningAdvice interface and override afterReturning(Object returnVal, Method method, Object[] arg, Object target) method in order to create AfterReturningAdvice implementation class.

• First parameter contains the return value of the business method or null, rest of the parameters is similar to before Advice method parameters.

Syntax Of  AfterReturningAdvice — afterReturning()Method

public void afterReturning(ObjectreturnVal, Method method, Object[] arg,

            Object target) throws Throwable {

        }

Steps for creating implementation for AfterreturningAdvice :-

1) Create a java file in com.gaurav.aop.advices package and name it as TraceLogAfterReturnMethodExecution.

2) Place the below code in that java file.

3) Create a java bean InternetClientService in the com.gaurav.aop.services package and place the below code in the bean file.

4) Create a xml bean file names spring-internet-client-service-beans-afteradvice.xml inside src folder and place the below code in that file.

5) Create a java file TraceLogMethodAfterAdviceClient.java in the package com.gaurav.aop.advices.client inside src folder.Place the below available code in that file.

 

TraceLogAfterReturnMethodExecution.java

package com.gaurav.aop.advices;

import java.lang.reflect.Method;

import org.springframework.aop.AfterReturningAdvice;

public class TraceLogAfterReturnMethodExecutionimplements AfterReturningAdvice {

    @Override

    public void afterReturning(Object returnVal, Method method, Object[] arg,

            Object target) throws Throwable {

        System.out

                .println("\n TraceLogAfterReturningAdvice:-Entered inside AfterReturningAdvice");

    }

}

InternetClientService.java

package com.gaurav.aop.services;

import org.springframework.transaction.IllegalTransactionStateException;

public class InternetClientService {

    private int internetUserId;

    private String internetUserName;

    private String connectionURL;

    public void setInternetUserId(int internetUserId) {

        this.internetUserId = internetUserId;

    }

    public void setInternetUserName(String internetUserName) {

        this.internetUserName = internetUserName;

    }

    public void setConnectionURL(String connectionURL) {

        this.connectionURL = connectionURL;

    }

    public void displayInternetUserId() {

        System.out.println("Internet User ID : " + this.internetUserId);

    }

    public void displayInternetUserName() {

        System.out.println("Internet User Name : " + this.internetUserName);

    }

    public void displayConnectionURL() {

        System.out.println("Connection URL in Internet is : "

                + this.connectionURL);

    }

    public void displayThrowException() {

        throw new IllegalTransactionStateException(internetUserName);

    }

}

spring-internet-client-service-beans-afteradvice.xml

<beans xmlns="http://www.springframework.org/schema/beans"

    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

    xsi:schemaLocation="http://www.springframework.org/schema/beans

        http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">

    <bean id="internetClientService" class="com.gaurav.aop.services.InternetClientService">

        <property name="internetUserId" value="315260" />

        <property name="internetUserName" value="Gaurav Kumar" />

        <property name="connectionURL" value="http://www.javatechtipssharedbygaurav.com/" />

    </bean>

    <bean id="traceLogAfterMethodBean" class="com.gaurav.aop.advices.TraceLogAfterReturnMethodExecution" />

    <bean id="internetClientServiceProxy"

                class="org.springframework.aop.framework.ProxyFactoryBean">

        <property name="target" ref="internetClientService" />

        <property name="interceptorNames">

            <list>

                <value>traceLogAfterMethodBean</value>

            </list>

        </property>

    </bean>

</beans>

TraceLogMethodAfterAdviceClient.java

package com.gaurav.aop.advices.client;

import org.springframework.context.ApplicationContext;

import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.gaurav.aop.services.InternetClientService;

public class TraceLogMethodAfterAdviceClient{

    public static void main(String[] args) {

        ApplicationContext appContext = new ClassPathXmlApplicationContext(

                new String[] { "spring-internet-client-service-beans-afteradvice.xml" });

        InternetClientService internetClientService = (InternetClientService) appContext

                .getBean("internetClientServiceProxy");

        System.out

                .println(" \n ##### InternetUser ID in client application is as below ");

        internetClientService.displayInternetUserId();

        System.out

                .println(" \n ##### InternetUser Name in client application is as below ");

        internetClientService.displayInternetUserName();

        System.out

                .println(" \n ##### Connection URL for Internet in client application is as below ");

        internetClientService.displayConnectionURL();

        try {

            internetClientService.displayThrowException();

        } catch (Exception e) {

        }

    }

}

Result:-