[SPRING] AOP - 관점 지향 프로그래밍

 

AOP (Aspect Oriented Programming) : 관점 지향 프로그래밍

- 공통 기능을 핵심 기능과 분리해 놓고, 공통 기능 중에서 핵심 기능에 적용하고자 하는 부분에 적용

 

 

기본 용어

1. Aspect : 공통 기능

2. Advice : Aspect 순수 기능 그 자체

3. Joinpoint : Advice를 적용해야 되는 부분 (메소드)

4. Pointcut : Joinpoint의 부분, 실제로 Advice가 적용된 부분

5. Weaving : Advice를 핵심 기능에 적용하는 행위

 

 

XML 기반 AOP 구현

 

0. 데이터 클래스

- Student.java

package com.spring.ex;

public class Student {
    private String name;
    private int age;
    private int gradeNum;
    private int classNum;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public int getGradeNum() {
        return gradeNum;
    }

    public void setGradeNum(int gradeNum) {
        this.gradeNum = gradeNum;
    }

    public int getClassNum() {
        return classNum;
    }

    public void setClassNum(int classNum) {
        this.classNum = classNum;
    }

    public void getStudentInfo() {
        System.out.println("이름 : " + getName());
        System.out.println("나이 : " + getAge());
        System.out.println("학년 : " + getGradeNum());
        System.out.println("반 : " + getClassNum());
    }
}

 

- Worker.java

package com.spring.ex;

public class Worker {
    private String name;
    private int age;
    private String job;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getJob() {
        return job;
    }

    public void setJob(String job) {
        this.job = job;
    }

    public void getWorkerInfo() {
        System.out.println("이름 : " + getName());
        System.out.println("나이 : " + getAge());
        System.out.println("직업 : " + getJob());
    }
}

 

1. 의존 설정 (pom.xml)

<!-- AOP -->
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId> aspectjweaver</artifactId>
            <version>1.7.4</version>
        </dependency>

의존 설정한 것이 들어갔는지 확인

 

 

2. 공통 기능의 클래스 제작

- Advice 역할

import org.aspectj.lang.ProceedingJoinPoint;

//공통 기능 클래스
public class LogAop {
    //공통 기능
    public Object loggerAop(ProceedingJoinPoint joinpoint) throws Throwable {
        String signatureStr = joinpoint.getSignature().toShortString();
        System.out.println(signatureStr + " is starting");
        long st = System.currentTimeMillis(); // start time

        try {
            //핵심 기능
            Object obj = joinpoint.proceed();
            return obj;
        } finally {
            long et = System.currentTimeMillis(); // end time
            System.out.println(signatureStr + " is finished");
            System.out.println(signatureStr + "경과 시간 : " + (et - st));
        }
    }
}

 

 

3. XML설정 파일에 Aspect 설정

<?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-3.2.xsd">

    <bean id="logAop" class="com.spring.ex.LogAop" />
    <aop:config>
        <aop:aspect id="logger" ref="logAop"> <!-- 공통 기능 -->
            <aop:pointcut expression="within(com.spring.ex.*)"
                id="publicM" />
            <aop:around pointcut-ref="publicM" method="loggerAop" />
        </aop:aspect>
    </aop:config>

    <bean id="student" class="com.spring.ex.Student">
        <property name="name" value="홍길동" />
        <property name="age" value="10" />
        <property name="gradeNum" value="3" />
        <property name="classNum" value="5" />
    </bean>

    <bean id="worker" class="com.spring.ex.Worker">
        <property name="name" value="홍길순" />
        <property name="age" value="25" />
        <property name="job" value="개발자" />
    </bean>

</beans>

 

 

4. Main

import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.GenericXmlApplicationContext;

public class Main {
    public static void main(String[] args) {
        AbstractApplicationContext ctx = new GenericXmlApplicationContext("classpath:CTX.xml");

        Student student = ctx.getBean("student", Student.class);
        student.getStudentInfo();

        Worker worker = ctx.getBean("worker", Worker.class);
        worker.getWorkerInfo();

        ctx.close();
    }
}

 

 

5. 실행

 

 

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JAVA 기반 AOP 구현

0. 데이터 클래스

- Student.java

- Worker.java

 

1. 의존 설정 (pom.xml)

 

2. @Aspect Annotation을 이용한 Aspect 클래스 구현

package com.spring.java;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;

//공통 기능 클래스
@Aspect
public class LogAop {
    // 공통 기능
    @Pointcut("within(com.spring.java.*)")
    private void pointcutMethod() {
        // 범위 지정을 위해 생성 - 내용 없음
    }
    @Around("pointcutMethod()") // 공통 기능이 어디서 실행 될지 지정
    public Object loggerAop(ProceedingJoinPoint joinpoint) throws Throwable {
        String signatureStr = joinpoint.getSignature().toShortString();
        System.out.println(signatureStr + " is starting");
        long st = System.currentTimeMillis(); // start time

        try {
            //핵심 기능
            Object obj = joinpoint.proceed();
            return obj;
        } finally {
            long et = System.currentTimeMillis(); // end time
            System.out.println(signatureStr + " is finished");
            System.out.println(signatureStr + "경과 시간 : " + (et - st));
        }
    }
}

 

3. XML 파일 설정

<?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-3.2.xsd">
    <aop:aspectj-autoproxy />
    <bean id="logAop" class="com.spring.java.LogAop" />

    <bean id="student" class="com.spring.java.Student">
        <property name="name" value="홍길갈동" />
        <property name="age" value="10" />
        <property name="gradeNum" value="3" />
        <property name="classNum" value="5" />
    </bean>

    <bean id="worker" class="com.spring.java.Worker">
        <property name="name" value="홍길순" />
        <property name="age" value="25" />
        <property name="job" value="개발자" />
    </bean>

</beans>

 

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프록시 (Proxy) : AOP 구현 방법

- Advice가 직접 구현하는게 아니라, 프록시를 통해 구현

- Client(호출부)와 Target(핵심기능) 사이에서 대행 역할

- 공통 기능 수행

- PC의 핵심 기능에 접근

 

 

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AspectJ Pointcut 표현식

- * : 모든

- . : 현재

- .. : 0개 이상