Spring AOP實現方式三之自動掃描注入【附源碼】

時間 2019-11-09

標籤 spring aop 實現方式自動掃描注入附源碼欄目 Spring 简体版

原文原文鏈接

註解AOP實現這裏惟一不一樣的就是application 裏面

不須要配置每一個bean都須要配置了，直接自動掃描

註冊，主要知識點是怎麼經過配置文件獲得bean，

注意類前面的@註解。

源碼結構：

一、首先咱們新建一個接口，love 談戀愛接口。

package com.spring.aop;

/**
 * 談戀愛接口
 * 
 * @author Administrator
 *
 */
public interface Love
{

    /*
     * 談戀愛方法
     */
    void fallInLove();
    void test() throws Exception;

}

二、咱們寫一個Person類實現Love接口類聲明前面加上了

@Component 不加這個咱們沒法經過載入xml配置文件找到。

package com.spring.aop;

import org.springframework.stereotype.Component;

/**
 * 人對象
 * 
 * @author luwenbin006@163.com
 *
 */
@Component
public class Person implements Love
{

    /*
     * 重寫談戀愛方法
     */
    @Override
    public void fallInLove()
    {
        System.out.println("談戀愛了...");
    }

    @Override
    public void test() throws Exception
    {
        // TODO Auto-generated method stub
        throw new Exception("我就說大家在一塊兒不會幸福的，你能拿我怎麼滴？");
    }

}

三、下面咱們來寫aop 註解通知類和前面有點不一樣哦 @Aspect前面加上了@Service

【執行方法前執行方法後執行方法先後也稱爲環繞方法方法執行過程當中拋出異常】

package com.spring.aop;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.After;
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.stereotype.Service;

/**
 * 註解方式 aop通知類
 * 
 * @author luwenbin006@163.com
 *
 */
@Service
@Aspect
public class LoveHelper
{

    @Pointcut("execution(* com.spring.aop.*..*(..))")
    private void loveMethod()
    {
    }// 定義一個切入點

    // 在調用方法以前執行 執行攔截包com.spring.aop.*下全部的方法
    @Before("execution(* com.spring.aop.*..*(..))")
    public void before(JoinPoint point) throws Throwable
    {
        System.out.println("before::method "
                + point.getTarget().getClass().getName() + "."
                + point.getSignature().getName());
        System.out.println("談戀愛以前必需要彼此瞭解！");
    }

    // 在調用方法先後執行
    @Around("execution(* com.spring.aop.*..*(..))")
    public Object around(ProceedingJoinPoint point) throws Throwable
    {
        System.out.println("around::method "
                + point.getTarget().getClass().getName() + "."
                + point.getSignature().getName());
        if (point.getArgs().length > 0)
        {

            return point.proceed(point.getArgs());

        }
        else
        {

            return point.proceed();
        }
    }

    // 在調用方法以後執行
    @After("execution(* com.spring.aop.*..*(..))")
    public void afterReturning(JoinPoint point) throws Throwable
    {
        System.out.println("method " + point.getTarget().getClass().getName()
                + "." + point.getSignature().getName());
        System.out.println("咱們已經談了5年了，最終仍是分手了！");
        // System.out.println("咱們已經談了5年了，最終步入告終婚的殿堂！");
    }

    // 當拋出異常時被調用
    @AfterThrowing(value = "execution(* com.spring.aop.*..*(..))", throwing = "ex")
    public void doThrowing(JoinPoint point, Throwable ex)
    {
        System.out.println("doThrowing::method "
                + point.getTarget().getClass().getName() + "."
                + point.getSignature().getName() + " throw exception");
        System.out.println(ex.getMessage());
    }

}

四、配置好application.xml 就配置好bean和aop通知類加上一句啓用註解模式

配置和自動掃描配置。

<?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:p="http://www.springframework.org/schema/p"
    xmlns:aop="http://www.springframework.org/schema/aop" xmlns:context="http://www.springframework.org/schema/context"
    xmlns:jee="http://www.springframework.org/schema/jee" xmlns:tx="http://www.springframework.org/schema/tx"
    xsi:schemaLocation="  
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd
        http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-4.0.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd">



    <!--組件掃描 -->
    <context:component-scan base-package="com.spring.aop" />
    <aop:aspectj-autoproxy />

    <!-- //定義掃描根路徑爲leot.test，不使用默認的掃描方式 <context:component-scan base-package="com.spring.aop" 
        use-default-filters="false"> // 掃描符合@Service @Repository的類 <context:include-filter 
        type="annotation" expression="org.springframework.stereotype.Service" /> 
        <context:include-filter type="annotation" expression="org.springframework.stereotype.Repository" 
        /> </context:component-scan> -->
</beans>

五、編寫咱們spring getBean 輔助工具類兩種方式，一種是實現 ApplicationContextAware

接口一種是繼承ApplicationObjectSupport

一、實現ApplicationContextAware接口

package com.spring.aop.springUtil;

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Service;

@Service
public class SpringContextHelper implements ApplicationContextAware
{

    private ApplicationContext context;

    // 提供一個接口，獲取容器中的Bean實例，根據名稱獲取
    public Object getBean(String beanName)
    {
        return context.getBean(beanName);
    }

    @Override
    public void setApplicationContext(ApplicationContext context)
            throws BeansException
    {
        this.context = context;

    }

}

二、繼承ApplicationObjectSupport類

package com.spring.aop.springUtil;

import org.springframework.context.support.ApplicationObjectSupport;
import org.springframework.stereotype.Service;

@Service
public class SpringContextHelper2 extends ApplicationObjectSupport
{

    // 提供一個接口，獲取容器中的Bean實例，根據名稱獲取
    public Object getBean(String beanName)
    {
        return getApplicationContext().getBean(beanName);
    }

}

六、咱們以前的測試類也仍是能夠運行的哦~~~

package com.spring.aop;

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

import com.spring.aop.Love;

public class LoveTest
{

    public static void main(String[] args)
    {
        ApplicationContext appCtx = new ClassPathXmlApplicationContext(
                "applicationContext.xml");
        Love love = (Love) appCtx.getBean("person");
        love.fallInLove();
        try
        {
            // 測試異常捕獲
            love.test();
        }
        catch (Exception e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

七、或者寫上Junit測試類

package com.love.test;

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

import com.spring.aop.Love;
import com.spring.aop.springUtil.SpringContextHelper;
import com.spring.aop.springUtil.SpringContextHelper2;

import junit.framework.TestCase;

public class LoveAopTest extends TestCase
{

    private SpringContextHelper helper;
    private SpringContextHelper2 helper2;
    ApplicationContext context;

    protected void setUp()
    {
        /* 開始test前的準備操做:初始化,獲取數據鏈接... */
        context = new ClassPathXmlApplicationContext("applicationContext.xml");
        helper = (SpringContextHelper) context.getBean("springContextHelper");
        helper2 = (SpringContextHelper2) context
                .getBean("springContextHelper2");

    }

    protected void tearDown()
    {
        /* 完成test後的清理工做:關閉文件, 關閉數據鏈接... */

    }

    public void testCase2()
    {

        Love love = (Love) helper.getBean("person");
        love.fallInLove();
        try
        {
            // 測試異常捕獲
            love.test();
        }
        catch (Exception e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
            assertTrue(true);
        }
    }

    public void testCase3()
    {

        Love love = (Love) helper2.getBean("person");
        love.fallInLove();
        try
        {
            // 測試異常捕獲
            love.test();
        }
        catch (Exception e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
            assertTrue(true);
        }
    }

}