AOP 统一处理exception

接上一篇《dubbox consumer获取provider的exception message》的内容。

使用AOP统一处理一些常用Exception，然后利用ExceptionMapper response数据到consumer

因为要自定义message，所以做的这么麻烦，不然直接全部在ExceptionMappe中处理就行，因为毕竟处理掉的是unchecked exception

//其实感觉需求有点莫名其妙。。

//重新补充，其实consumer真正需要的是checked exception，所以下面的实现对其作用不大。

资料：

http://ugibb510.iteye.com/blog/1762792

http://suntengjiao1.blog.163.com/blog/static/99211088201284112149284/

http://www.cnblogs.com/peida/archive/2013/04/26/3038503.html

http://www.cnblogs.com/peida/archive/2013/04/24/3036689.html

配置文件中增加：

xmlns:aop="http://www.springframework.org/schema/aop"

<pre name="code" class="html">http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-3.0.xsd"

<pre name="code" class="html"><aop:aspectj-autoproxy/>

定义注解：

import java.lang.annotation.*;

@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface MyAnnotation {
    //提供 default 即可在使用是缺失
    String DataAccessEM() default "";//DataAccessException 自定义描述
    String DuplicateKeyEM() default "";//DuplicateKeyException 自定义描述
    String DfaultEM() default "";//Exception 自定义描述

}

定义切面：

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.AfterThrowing;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.stereotype.Component;

import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.Response;

/**
 * Created by leedongwei on 15/10/20.
 */
@Aspect
@Component //注入依赖
public class MyAspect {

    @AfterThrowing(pointcut="within(com.lee.test..*) && @annotation(ma)", throwing="ex")
    public void addMyTest(JoinPoint jp, MyAnnotation ma, Exception ex){

   //记录日志
        if(ex instanceof DataAccessException){
            System.out.println("in DataAccessException");
            logger.error(ea.DataAccessEM(), ex.getMessage());
            throw new WebApplicationException(ea.DataAccessEM(), Response.Status.BAD_REQUEST);

        }else if(ex instanceof DuplicateKeyException){
            System.out.println("in DuplicateKeyException");
            logger.error(ea.DataAccessEM(), ex.getMessage());
            throw new WebApplicationException(ea.DataAccessEM(), Response.Status.CONFLICT);

        }else if(ex instanceof WebApplicationException){
            System.out.println("in WebApplicationException");
            logger.error("WebApplicationException", ex.getMessage());
            //donothing
            return;
        }
        System.out.println("in DfaultEM,end");
        //除了指定被处理的,其余的都记得记录logger,为后台提供default message 和code

        throw new WebApplicationException(ea.DfaultEM(), Response.Status.INTERNAL_SERVER_ERROR);

    }
}

配置文件中增加：

 <bean id="logAspect" class="com.lee.test.MyAspect">

    </bean>

测试：

 @MyAnnotation(DataAccessEM = "dataAccessEm lee!",DuplicateKeyEM = "duplicateKeyEm lee!",DfaultEM = "defaultem lee!")
//    @MyAnnotation()
    public User getUser(@PathParam("id") Long id) {
        if (RpcContext.getContext().getRequest(HttpServletRequest.class) != null) {
            System.out.println("Client IP address from RpcContext: " + RpcContext.getContext().getRequest(HttpServletRequest.class).getRemoteAddr());
        }
        if (RpcContext.getContext().getResponse(HttpServletResponse.class) != null) {
            System.out.println("Response object from RpcContext: " + RpcContext.getContext().getResponse(HttpServletResponse.class));
        }
//        int a = 1/0;//Exception test
        throw new WebApplicationException("in getUser ex", Response.Status.CONFLICT);

//        return userService.getUser(id);
    }