spring mvc controller中的异常封装

http://abc08010051.iteye.com/blog/2031992

一直以来都在用spring mvc做mvc框架，我使用的不是基于注解的，还是使用的基于xml的，在controller里一般都会加上一个异常捕捉，能分析出来的异常，提示出具体信息，不能预料的异常，返回一个统一的异常提示信息，未封装前的代码为：

public ModelAndView addBigDeal(HttpServletRequest request, HttpServletResponse response) throws Exception {
    JSONObject jsonObject = new JSONObject();
    try {
        String sessionId = WebUtils.getStringValue(request, "sessionId", true);
        String pl_id = WebUtils.getStringValue(request, "pl_id", true);
        String vsr_id = WebUtils.getStringValue(request, "vsr_id", true);
        String cmnts = WebUtils.getStringValue(request, "cmnts", false);
        if (!StringUtils.isBlank(cmnts)) {
            cmnts = new String(Base64Utils.decode(cmnts), "UTF-8");
        }
        JSONObject result = new JSONObject();
        result.put("dataId", this.storeVsrService.addBigDeal(pl_id, vsr_id, cmnts));
        jsonObject.put("data", result);
        jsonObject.put("status", CommonUtils.getSubStatus(" add bigDeal  successfully!"));
    } catch (GenericException e) {
        jsonObject.put("status", CommonUtils.getSubStatus(false, "000001", e.getMsg()));
        jsonObject.put("data", "");
        logger.error("error !", e);
    } catch (Exception e) {
        jsonObject.put("status", CommonUtils.getSubStatus(false, "000001", "网络或其他错误，请联系管理员！"));
        jsonObject.put("data", "");
        logger.error("error !", e);
    }
    response.getWriter().write(jsonObject.toString());
    return null;
}

 GenericException为自定义异常的父类，自定义的异常都要继承该类

上面代码的缺点：每写一个方法时，都要重复的写这一段：

try {

        } catch (GenericException e) {
            jsonObject.put("status", CommonUtils.getSubStatus(false, "000001", e.getMsg()));
            jsonObject.put("data", "");
            logger.error("error !", e);
        } catch (Exception e) {
            jsonObject.put("status", CommonUtils.getSubStatus(false, "000001", "网络或其他错误，请联系管理员！"));
            jsonObject.put("data", "");
            logger.error("error !", e);
        }

因为每一个controller都会继承MultiActionController，现在在每一个controller和自己定义的controller里抽象一层，因为所有controller里的方法入口

都是MultiActionController里的handleRequestInternal方法，所以重写该方法，把异常捕捉放到这个统一的入口和出口里，

新增加的类为BaseController，封装后的代码如下：

package com.intel.store.controller;

import com.intel.store.common.CommonUtils;
import com.intel.store.exception.GenericException;
import org.codehaus.jettison.json.JSONObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.multiaction.MultiActionController;
import org.springframework.web.servlet.mvc.multiaction.NoSuchRequestHandlingMethodException;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 *  mvc controller类的基类，用于一般controller的继承，
 *  把异常控制模块提取到基类，
 *  使开发更加简洁，快速
 * Created with IntelliJ IDEA.
 * User: malone
 * Date: 14-3-17
 * Time: 上午10:21
 * To change this template use File | Settings | File Templates.
 */
public class BaseController<T extends BaseController<T>> extends MultiActionController {

    private Class<T> subclass;

    private Logger logger = LoggerFactory.getLogger(subclass);

    BaseController() {
        subclass = ((Class)((ParameterizedType)(this.getClass().getGenericSuperclass())).getActualTypeArguments()[0]);
        logger = LoggerFactory.getLogger(subclass);
    }

    @Override
    protected ModelAndView handleRequestInternal(HttpServletRequest request, HttpServletResponse response)
            throws Exception {
        JSONObject jsonObject = new JSONObject();
        try {
            String methodName = this.getMethodNameResolver().getHandlerMethodName(request);
            Object obj = invokeNamedMethod(methodName, request, response);
            System.out.println(obj.getClass());
            return invokeNamedMethod(methodName, request, response);
        } catch (NoSuchRequestHandlingMethodException ex) {
            return handleNoSuchRequestHandlingMethod(ex, request, response);
        } catch (GenericException e) {
            jsonObject.put("status", CommonUtils.getSubStatus(false, "000001", e.getMsg()));
            jsonObject.put("data", "");
            logger.error(e.getMsg(), e);
            response.getWriter().write(jsonObject.toString());
            return null;
        } catch (Exception e) {
            jsonObject.put("status", CommonUtils.getSubStatus(false, "000001",
                    "网络或其他错误，请联系管理员！"));
            jsonObject.put("data", "");
            logger.error("error !", e);
            response.getWriter().write(jsonObject.toString());
            return null;
        }
    }

}

这样以来所有的自定义Controller只需要继承BaseController， 然后在每个方法里就需要些try catch异常捕捉模块了，如下所示

public ModelAndView addBigDeal(HttpServletRequest request, HttpServletResponse response) throws Exception {
    JSONObject jsonObject = new JSONObject();
        String sessionId = WebUtils.getStringValue(request, "sessionId", true);
        String pl_id = WebUtils.getStringValue(request, "pl_id", true);
        String vsr_id = WebUtils.getStringValue(request, "vsr_id", true);
        String cmnts = WebUtils.getStringValue(request, "cmnts", false);
        if (!StringUtils.isBlank(cmnts)) {
            cmnts = new String(Base64Utils.decode(cmnts), "UTF-8");
        }
        JSONObject result = new JSONObject();
        result.put("dataId", this.storeVsrService.addBigDeal(pl_id, vsr_id, cmnts));
        jsonObject.put("data", result);
        jsonObject.put("status", CommonUtils.getSubStatus(" add bigDeal  successfully!"));

    response.getWriter().write(jsonObject.toString());
    return null;
}