SpringBoot自定义错误信息，SpringBoot适配Ajax请求

SpringBoot自定义错误信息，SpringBoot自定义异常处理类，

SpringBoot异常结果处理适配页面及Ajax请求，

SpringBoot适配Ajax请求

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©Copyright 蕃薯耀 2018年3月29日

http://www.cnblogs.com/fanshuyao/

附件&源码下载见：http://fanshuyao.iteye.com/blog/2414865

一、自定义异常处理类：

Java代码

import java.util.HashMap;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import com.lqy.springboot.component.CustomErrorAttribute;
@ControllerAdvice
public class CustomExceptionHandler {
/**
* 自定义异常数据
* 缺点，没有适配页面和Ajax请求，返回的数据都是json数据
* @param req
* @return
*/
/*@ResponseBody
@ExceptionHandler(Exception.class)
public Map<String, Object> exceptionHandler(HttpServletRequest req){
Map<String, Object> map = new HashMap<String, Object>();
map.put("errorCode", 500);
map.put("errorMsg", "错误信息");
map.put("errorSystem", "errorSystem");
return map;
}*/
/**
* 自定义异常数据
* 适配页面和Ajax请求
* 注解ExceptionHandler(Exception.class)的Exception.class可以替换成自己定义的错误异常类
* @param req
* @return
*/
@ExceptionHandler(Exception.class)
public String exceptionHandler(HttpServletRequest req){
Map<String, Object> map = new HashMap<String, Object>();
map.put("errorCode", 500);
map.put("errorMsg", "错误信息");
map.put("errorSystem", "errorSystem");
req.setAttribute(CustomErrorAttribute.CUSTOM_ERROR_MAP_NAME, map);
//传入自己的错误代码，必须的，否则不会进入自定义错误页面，见：org.springframework.boot.autoconfigure.web.AbstractErrorController
req.setAttribute("javax.servlet.error.status_code", 500);
//转发到springBoot错误处理请求，能适配网页和Ajax的错误处理
//请求/error后，会进入BasicErrorController(@RequestMapping("${server.error.path:${error.path:/error}}"))
//页面的数据显示处理是使用：errorAttributes.getErrorAttributes获取显示的，是AbstractErrorController的方法
//当需要把自己定义的Map错误信息传递到错误提示页面时，
//可以编写一个自定义错误属性类处理：CustomErrorAttribute，继承DefaultErrorAttributes类，
//重写getErrorAttributes(RequestAttributes requestAttributes, boolean includeStackTrace)方法
return "forward:/error";
}
}

异常捕捉后请求转发到

Java代码

return "forward:/error";

是为了让SpringBoot底层处理，协助系统适配页面返回结果和Ajax返回结果：当是页面打开时，会跳转到相应的错误页面显示异常信息，当是Ajax请求或者使用工具请求时，返回的json字符串。（下面有图）

SpringBoot适配页面返回结果和Ajax返回结果的代码如下：

Java代码

@RequestMapping(produces = "text/html")
public ModelAndView errorHtml(HttpServletRequest request,
HttpServletResponse response) {
HttpStatus status = getStatus(request);
Map<String, Object> model = Collections.unmodifiableMap(getErrorAttributes(
request, isIncludeStackTrace(request, MediaType.TEXT_HTML)));
response.setStatus(status.value());
ModelAndView modelAndView = resolveErrorView(request, response, status, model);
return (modelAndView == null ? new ModelAndView("error", model) : modelAndView);
}
@RequestMapping
@ResponseBody
public ResponseEntity<Map<String, Object>> error(HttpServletRequest request) {
Map<String, Object> body = getErrorAttributes(request,
isIncludeStackTrace(request, MediaType.ALL));
HttpStatus status = getStatus(request);
return new ResponseEntity<Map<String, Object>>(body, status);
}

二、自定义异常信息传递类

Java代码

import java.util.Map;
import org.springframework.boot.autoconfigure.web.DefaultErrorAttributes;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestAttributes;
@Component
public class CustomErrorAttribute extends DefaultErrorAttributes {
public static final String CUSTOM_ERROR_MAP_NAME = "customErrorMap";
@Override
public Map<String, Object> getErrorAttributes(RequestAttributes requestAttributes, boolean includeStackTrace) {
Map<String, Object> map = super.getErrorAttributes(requestAttributes, includeStackTrace);
//设置传递自己定义的错误信息
map.put(CUSTOM_ERROR_MAP_NAME, requestAttributes.getAttribute(CUSTOM_ERROR_MAP_NAME, RequestAttributes.SCOPE_REQUEST));
return map;
}
}