dubbo rpc调用抛出的Exception处理

关于dubbo的Exception堆栈被吃处理，网上已经有比较多的解决方法，在我们的应用场景中，不希望RPC调用对方抛出业务exception，而是通过Resp中的errorCode，errorMsg来处理，例如有如下的定义：

    @Override
    public ResultModel<String> createExpress(CreateExpressDTO dto) {
        // 参数验证
        String group = "";
        if (StringUtils.isNotBlank(dto.getPartyId())) {
            group = Group.PARTY_TYPE_PARTY;
        } else if (DictCons.BANK_ACCOUNT_TYPE__PUBLIC.equals(dto.getBankAccountType())) {
            group = Group.PARTY_TYPE_NOT_PARTY_PUB;
        } else {
            group = Group.PARTY_TYPE_NOT_PARTY_PRI;
        }
        ValidationResult validationResult = ValidationUtils.validateEntity(group, dto);
        if (!validationResult.isSuccess()) {
            return new ResultModel<>(ErrorCons.ERR_BS_BAD_PARAM,
                    FastJsonUtil.serializeFromObject(validationResult.getErrorPair()));
        }
此处省去N行。。。。。

假设createExpress执行异常的时候，我们希望错误通过ResultModel<String>而不是RuntimeException回去，dubbo的exceptionfilter不符合我们的要求，如果要改动的话，需要到序列化层进行修改（原来在自己开发的RPC框架上就是这么处理的）。这种情况，只能借助AOP，如下：

package tf56.lf.common.advice;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.reflect.MethodSignature;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.InitializingBean;

import tf56.lf.base.ResultModel;
import tf56.lf.base.metadata.err.ErrorCons;
import tf56.lf.common.exception.LfException;

import com.alibaba.fastjson.JSON;

@Aspect
public class ServiceAroundAdvice implements InitializingBean {
    
    private static final Logger logger = LoggerFactory.getLogger(ServiceAroundAdvice.class);
    
    @Around("execution(* tf56.lf.*.service..*(..))")  
    public Object processDubboService(ProceedingJoinPoint jp) throws Throwable{
        long begin = System.currentTimeMillis();
        logger.info("开始执行" + jp.getSignature() + "参数:" + JSON.toJSONString(jp.getArgs()));
        Object result = null;
        try {
            result = jp.proceed();
        } catch (Exception e) {
            logger.error("",e);
            Class<?> clz = ((MethodSignature)jp.getSignature()).getMethod().getReturnType();
            if ("void".equals(clz.getName())) {
                return result;
            }
            
            ResultModel<?> resultModel = ((ResultModel<?>)clz.newInstance());
            if (e instanceof LfException) {
                resultModel.setCode(((LfException) e).getCode());
                resultModel.setMsg(((LfException) e).getErrorInfo());
            } else {
                resultModel.setCode(ErrorCons.ERR_FAIL);    
            }
            result = resultModel;
        }
        long end = System.currentTimeMillis();
        logger.info("完成执行" + jp.getSignature() + ",共" + (end - begin) + "毫秒!");
        return result;
    }

    @Override
    public void afterPropertiesSet() throws Exception {
        logger.info("加载" + this.getClass().getCanonicalName() + "成功!");
    }
}

增加配置如下：

<?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:tx="http://www.springframework.org/schema/tx"
           xmlns:aop="http://www.springframework.org/schema/aop"
           xmlns:context="http://www.springframework.org/schema/context"
           xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
        http://www.springframework.org/schema/tx 
        http://www.springframework.org/schema/tx/spring-tx-4.3.xsd
        http://www.springframework.org/schema/aop 
        http://www.springframework.org/schema/aop/spring-aop-4.3.xsd
       http://www.springframework.org/schema/context
       http://www.springframework.org/schema/context/spring-context.xsd">

    <bean class="tf56.lf.common.advice.ServiceAroundAdvice"></bean>
    <aop:aspectj-autoproxy proxy-target-class="true" />

这样就可以保证所有的Exception都会被优雅的处理，同时泛型也都能恰当的被处理。