共兩種
- 實(shí)現(xiàn)接口
- 使用注解(簡單)
最近做項(xiàng)目在通過異潮拗矗控制返回值code碼,初步思路是定義一個(gè)全局異常處理器,上面剛說到有兩種方法,先講第一種.
HandlerExceptionResolver
springmvc給我們提供了可以擴(kuò)展的接口HandlerExceptionResolver,實(shí)現(xiàn)此接口,重寫處理異常方法.此方法有些不好用的是在返回值上面.強(qiáng)制我們返回model and view,如果想要返回json,則還需要自己轉(zhuǎn)換一層,下文寫到了.
/*
* Copyright 2002-2018 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.web.servlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.lang.Nullable;
/**
* Interface to be implemented by objects that can resolve exceptions thrown during
* handler mapping or execution, in the typical case to error views. Implementors are
* typically registered as beans in the application context.
*
* <p>Error views are analogous to JSP error pages but can be used with any kind of
* exception including any checked exception, with potentially fine-grained mappings for
* specific handlers.
*
* @author Juergen Hoeller
* @since 22.11.2003
*/
public interface HandlerExceptionResolver {
/**
* Try to resolve the given exception that got thrown during handler execution,
* returning a {@link ModelAndView} that represents a specific error page if appropriate.
* <p>The returned {@code ModelAndView} may be {@linkplain ModelAndView#isEmpty() empty}
* to indicate that the exception has been resolved successfully but that no view
* should be rendered, for instance by setting a status code.
* @param request current HTTP request
* @param response current HTTP response
* @param handler the executed handler, or {@code null} if none chosen at the
* time of the exception (for example, if multipart resolution failed)
* @param ex the exception that got thrown during handler execution
* @return a corresponding {@code ModelAndView} to forward to,
* or {@code null} for default processing in the resolution chain
*/
@Nullable
ModelAndView resolveException(
HttpServletRequest request, HttpServletResponse response, @Nullable Object handler, Exception ex);
}
如果model and view要轉(zhuǎn)換成普通json返回,則需要手動(dòng)轉(zhuǎn)換一層:
MappingJackson2JsonView jackson2JsonView = new MappingJackson2JsonView();
//設(shè)置返回的json map
Map returnData = Maps.newHashMap();
//TODO add return data
jackson2JsonView.setAttributesMap(returnData);
ModelAndView view = new ModelAndView();
view.setView(jackson2JsonView);
return view;
簡單方法(使用注解)
在開始說這個(gè)之前,我們要先了解一下相關(guān)的兩個(gè)注解
- @ControllerAdvice,注釋大致意思就是 controllerAdvice是一個(gè)用于定義@ExceptionHadnler的Component注解.適用于所有的@RequestMapping方法
- @ExceptionHandler:需要處理的異常,如果不傳值默認(rèn)處理所有異常
使用方法:
import com.immomo.moaservice.live.assess.impl.exception.ActivityAnalyticsException;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestControllerAdvice;
/**
* @author: hman
* @date 2018-11-05
* @desc: 全局異常處理
*/
@RestControllerAdvice
public class ActivityExceptionHandler {
@ExceptionHandler(ActivityAnalyticsException.class)
@ResponseBody
public ResultUtil resolveException(ActivityAnalyticsException e) {
return ResultUtil.build(e.getCodeEnum());
}
}
