Spring Aop与AspectJ springaop与aspectj的关系

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colddawn 2024-03-26 14:12:54

文章标签 Spring Aop与AspectJ spring java 后端开发语言 文章分类 架构后端开发

区别

AspectJ

AspectJ是一个面向切面的框架，它扩展了Java语言。AspectJ定义了AOP语法，所以它有一个专门的编译器用来生成遵守Java字节编码规范的Class文件。

Spring AOP

Spring提供了四种类型的AOP支持

基于经典的SpringAOP
纯POJO切面
@ASpectJ注解驱动的切面
注入式AspectJ切面（其实与Spring并无多大的关系，这个就是使用AspectJ这个框架实现Aop编程）

基于经典的SpringAOP

其使用ProxyFactoryBean创建。

增强（通知）的类型有：

前置通知：org.springframework.aop.MethodBeforeAdvice
后置通知：org.springframework.aop.AfterReturningAdvice
环绕通知：org.aopalliance.intercept.MethodInterceptor
异常通知：org.springframework.aop.ThrowsAdvice

public interface IBookDao {
    public int add()
    public int delete();
}
 
public class BookDaoImpl implements IBookDao{
    public int add() {
        System.out.println("正在添加图书...");
        return 0;
    }
    public int delete() {
        System.out.println("正在删除图书...");
        return 0;
    }
}
 
//实现了MethodInterceptor的环绕增强类
public class MyAdvice implements MethodInterceptor{
 
    public Object invoke(MethodInvocation invocation) throws Throwable {
        System.out.println("Around Advice before method invocation");
        Object o = invocation.proceed();
        System.out.println("Around Advice after method invocation");
        return o;
    }
}

将每一个连接点都当做切点（拦截每一个方法）

<bean id="bookDao" class="com.njust.learning.spring.service.BookDaoImpl"></bean>
 
    <bean id="myadvice" class="com.njust.learning.spring.aop.MyAdvice"></bean>
 
    <bean id="bookDaoProxy" class="org.springframework.aop.framework.ProxyFactoryBean">
        <property name="target" ref="bookDao"/>
        <property name="proxyInterfaces" value="com.njust.learning.spring.service.IBookDao"/>
        <property name="interceptorNames" value="myadvice"/>
</bean>

使用RegexMethodPointcutAdvisor针对某些特定的方法进行拦截增强

<bean id="bookDao" class="com.njust.learning.spring.service.BookDaoImpl"></bean>

   <bean id="myadvice" class="com.njust.learning.spring.aop.MyAdvice"></bean>


   <bean id="rmpAdvisor" class="org.springframework.aop.support.RegexpMethodPointcutAdvisor">
       <!--patterns,如果有多个指定的值的话，可以使用，隔开，例如value=".*add,.*delete"-->
       <property name="patterns" value=".*add"/>
       <property name="advice" ref="myadvice"/>
   </bean>
<!--使用的时候使用这个id，而不是原始的那个id-->
   <bean id="bookDaoProxy" class="org.springframework.aop.framework.ProxyFactoryBean">
       <property name="target" ref="bookDao"/>
       <property name="proxyInterfaces" value="com.njust.learning.spring.service.IBookDao"/>
       <property name="interceptorNames" value="rmpAdvisor"/>
   </bean>

注意:

像上面这样，每定义一个dao都需要定义一个ProxyFactoryBean，显得很麻烦，所以我们引入自动代理，也就是自动创建代理对象

Spring Aop与AspectJ springaop与aspectj的关系_Spring Aop与AspectJ

BeanNameAutoProxyCreator

<bean id="bookDao" class="com.njust.learning.spring.service.BookDaoImpl"></bean>
 
    <bean id="myadvice" class="com.njust.learning.spring.aop.MyAdvice"></bean>
 
    <bean id="rmpAdvisor" class="org.springframework.aop.support.RegexpMethodPointcutAdvisor">
        <!--patterns,如果有多个指定的值的话，可以使用，隔开，例如value=".*add,.*delete"-->
        <property name="patterns" value=".*add"/>
        <property name="advice" ref="myadvice"/>
    </bean>
 
    <bean class="org.springframework.aop.framework.autoproxy.BeanNameAutoProxyCreator">
        <property name="beanNames" value="*Dao"></property>
        <property name="interceptorNames" value="rmpAdvisor"></property>
    </bean>

DefaultAdvisorAutoProxyCreator

<bean id="bookDao" class="com.njust.learning.spring.service.BookDaoImpl"></bean>
 
    <bean id="myadvice" class="com.njust.learning.spring.aop.MyAdvice"></bean>
 
    <bean id="rmpAdvisor" class="org.springframework.aop.support.RegexpMethodPointcutAdvisor">
        <!--patterns,如果有多个指定的值的话，可以使用，隔开，例如value=".*add,.*delete"-->
        <property name="patterns" value=".*add"/>
        <property name="advice" ref="myadvice"/>
    </bean>
 
    <!--根据切面中生成信息生成代理-->
    <bean class="org.springframework.aop.framework.autoproxy.DefaultAdvisorAutoProxyCreator"/>

纯POJO切面，需要使用XML进行配置

public interface IBookDao {
    public int add();
    public int delete();
}
 
public class BookDaoImpl implements IBookDao{
 
    public int add() {
        int a = 1/0;
        System.out.println("正在添加图书...");
        return 0;
    }
 
    public int delete() {
        System.out.println("正在删除图书...");
        return 0;
    }
}

public class PojoAdvice {
    public void before(){
        System.out.println("前置通知");
    }
    public void after(Object returnval){
        System.out.println("后置通知"+"，处理后的结果为："+returnval);
    }
    public Object around(ProceedingJoinPoint proceedingJoinPoint) throws Throwable {
        System.out.println("环绕前置增强...");
        Object o = proceedingJoinPoint.proceed();
        System.out.println("环绕后置增强...");
        return o;
    }
    public void afterThrowing(Throwable e){
        System.out.println("异常通知:"+e.getMessage());
    }
}

<bean id="bookDao" class="com.njust.learning.spring.service.BookDaoImpl"></bean>
 
    <bean id="pojoAdvice" class="com.njust.learning.spring.pojoaop.PojoAdvice"></bean>
 
    <aop:config>
        <aop:pointcut id="p" expression="execution (* *.add(..))"/>
        <aop:aspect ref="pojoAdvice">
            <aop:before method="before" pointcut-ref="p"></aop:before>
            <!--通过设置returning来将返回值传递给通知-->
            <aop:after-returning method="after" pointcut-ref="p" returning="returnval"/>
            <aop:around method="around" pointcut-ref="p"/>
            <!--通过设置returning来将异常对象传递给通知-->
            <aop:after-throwing method="afterThrowing" pointcut-ref="p" throwing="e"/>
        </aop:aspect>
    </aop:config>