Spring全局异常处理的三种方式

来源：互联网发布：搞笑问题及答案知乎编辑：程序博客网时间：2024/06/07 13:09

在J2EE项目的开发中，不管是对底层的数据库操作过程，还是业务层的处理过程，还是控制层的处理过程，都不可避免会遇到各种可预知的、不可预知的异常需要处理。每个过程都单独处理异常，系统的代码耦合度高，工作量大且不好统一，维护的工作量也很大。那么，能不能将所有类型的异常处理从各处理过程解耦出来，这样既保证了相关处理过程的功能较单一，也实现了异常信息的统一处理和维护？答案是肯定的。下面将介绍使用Spring MVC统一处理异常的解决和实现过程

使用Spring MVC提供的SimpleMappingExceptionResolver
实现Spring的异常处理接口HandlerExceptionResolver 自定义自己的异常处理器
使用@ExceptionHandler注解实现异常处理
(一) SimpleMappingExceptionResolver
使用这种方式具有集成简单、有良好的扩展性、对已有代码没有入侵性等优点，但该方法仅能获取到异常信息，若在出现异常时，对需要获取除异常以外的数据的情况不适用。

@Configuration@EnableWebMvc@ComponentScan(basePackages = {"com.balbala.mvc.web"})public class WebMVCConfig extends WebMvcConfigurerAdapter{  @Bean    public SimpleMappingExceptionResolver simpleMappingExceptionResolver()    {        SimpleMappingExceptionResolver b = new SimpleMappingExceptionResolver();        Properties mappings = new Properties();        mappings.put("org.springframework.web.servlet.PageNotFound", "page-404");        mappings.put("org.springframework.dao.DataAccessException", "data-access");        mappings.put("org.springframework.transaction.TransactionException", "transaction-Failure");        b.setExceptionMappings(mappings);        return b;    }}

看不懂上面的配置请查看该链接

(二) HandlerExceptionResolver
相比第一种来说,HandlerExceptionResolver能准确显示定义的异常处理页面,达到了统一异常处理的目标
1.定义一个类实现HandlerExceptionResolver接口,这次贴一个自己以前的代码

package com.athena.common.handler;import com.athena.common.constants.ResponseCode;import com.athena.common.exception.AthenaException;import com.athena.common.http.RspMsg;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.web.servlet.HandlerExceptionResolver;import org.springframework.web.servlet.ModelAndView;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import java.io.IOException;import java.io.PrintWriter;/**   * Created by sam on 15/4/14.  */public class GlobalHandlerExceptionResolver implements HandlerExceptionResolver {    private static final Logger LOG = LoggerFactory.getLogger(GlobalHandlerExceptionResolver.class);                    /**         * 在这里处理所有得异常信息         */       @Override       public ModelAndView resolveException(HttpServletRequest req,                                         HttpServletResponse resp, Object o, Exception ex) {          ex.printStackTrace();            if (ex instanceof AthenaException) {               //AthenaException为一个自定义异常           ex.printStackTrace();                    printWrite(ex.toString(), resp);                return new ModelAndView();          }           //RspMsg为一个自定义处理异常信息的类         //ResponseCode为一个自定义错误码的接口       RspMsg unknownException = null;             if (ex instanceof NullPointerException) {                   unknownException = new RspMsg(ResponseCode.CODE_UNKNOWN, "业务判空异常", null);       } else {                     unknownException = new RspMsg(ResponseCode.CODE_UNKNOWN, ex.getMessage(), null);        }                 printWrite(unknownException.toString(), resp);              return new ModelAndView();      }     /**        * 将错误信息添加到response中        *        * @param msg        * @param response        * @throws IOException        */       public static void printWrite(String msg, HttpServletResponse response) {               try {                        PrintWriter pw = response.getWriter();                     pw.write(msg);                    pw.flush();                    pw.close();                } catch (Exception e) {                       e.printStackTrace();                }       }}

2.加入spring的配置中,这里只贴出了相关部分

import com.athena.common.handler.GlobalHandlerExceptionResolver;import org.springframework.context.annotation.Bean;import com.athena.common.handler.GlobalHandlerExceptionResolver;import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;/**   * Created by sam on 15/4/14.  */public class WebSpringMvcConfig extends WebMvcConfigurerAdapter {    @Bean   public GlobalHandlerExceptionResolver globalHandlerExceptionResolver() {      return new GlobalHandlerExceptionResolver();   }}

(三)@ExceptionHandler
这是笔者现在项目的使用方式,这里也仅贴出了相关部分
1.首先定义一个父类,实现一些基础的方法

package com.balabala.poet.base.spring;import com.google.common.base.Throwables;import com.raiyee.poet.base.exception.MessageException;import com.raiyee.poet.base.utils.Ajax;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.core.annotation.AnnotationUtils;import org.springframework.http.HttpStatus;import org.springframework.web.bind.annotation.ResponseStatus;import org.springframework.web.servlet.ModelAndView;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import java.io.IOException;import java.io.PrintWriter;import java.util.Date;public class BaseGlobalExceptionHandler {         protected static final Logger logger = null;        protected static final String DEFAULT_ERROR_MESSAGE = "系统忙，请稍后再试";      protected ModelAndView handleError(HttpServletRequest req, HttpServletResponse rsp, Exception e, String viewName, HttpStatus status) throws Exception {             if (AnnotationUtils.findAnnotation(e.getClass(), ResponseStatus.class) != null)                throw e;              String errorMsg = e instanceof MessageException ? e.getMessage() : DEFAULT_ERROR_MESSAGE;                 String errorStack = Throwables.getStackTraceAsString(e);            getLogger().error("Request: {} raised {}", req.getRequestURI(), errorStack);                if (Ajax.isAjax(req)) {                      return handleAjaxError(rsp, errorMsg, status);            }                 return handleViewError(req.getRequestURL().toString(), errorStack, errorMsg, viewName);       }        protected ModelAndView handleViewError(String url, String errorStack, String errorMessage, String viewName) {                  ModelAndView mav = new ModelAndView();                 mav.addObject("exception", errorStack);                  mav.addObject("url", url);               mav.addObject("message", errorMessage);            mav.addObject("timestamp", new Date());                  mav.setViewName(viewName);              return mav;          }         protected ModelAndView handleAjaxError(HttpServletResponse rsp, String errorMessage, HttpStatus status) throws IOException {                    rsp.setCharacterEncoding("UTF-8");                   rsp.setStatus(status.value());                  PrintWriter writer = rsp.getWriter();            writer.write(errorMessage);                    writer.flush();                    return null;          }         public Logger getLogger() {                  return LoggerFactory.getLogger(BaseGlobalExceptionHandler.class);     } }

2.针对你需要捕捉的异常实现相对应的处理方式

package com.balabala.poet.base.spring;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.http.HttpStatus;import org.springframework.web.bind.annotation.ControllerAdvice;import org.springframework.web.bind.annotation.ExceptionHandler;import org.springframework.web.bind.annotation.ResponseStatus;import org.springframework.web.servlet.ModelAndView;import org.springframework.web.servlet.NoHandlerFoundException;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;@ControllerAdvicepublic class GlobalExceptionHandler extends BaseGlobalExceptionHandler {          //比如404的异常就会被这个方法捕获      @ExceptionHandler(NoHandlerFoundException.class)          @ResponseStatus(HttpStatus.NOT_FOUND)           public ModelAndView handle404Error(HttpServletRequest req, HttpServletResponse rsp, Exception e) throws Exception {                 return handleError(req, rsp, e, "error-front", HttpStatus.NOT_FOUND);           }          //500的异常会被这个方法捕获      @ExceptionHandler(Exception.class)            @ResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR)       public ModelAndView handleError(HttpServletRequest req, HttpServletResponse rsp, Exception e) throws Exception {              return handleError(req, rsp, e, "error-front", HttpStatus.INTERNAL_SERVER_ERROR);        }         //TODO  你也可以再写一个方法来捕获你的自定义异常     //TRY NOW!!!      @Override          public Logger getLogger() {                  return LoggerFactory.getLogger(GlobalExceptionHandler.class);          }  }

以上就三种处理方式,希望对大家有点帮助~

转载地址

1 0