15、SpringBoot-CRUD错误处理机制（2）

public class UserException extends RuntimeException {
    public UserException() {
        super("the user is not exist!");
    }
}

<h1>status：[[${status}]]</h1>
<h1>timestamp：[[${timestamp}]]</h1>
<h1>error：[[${error}]]</h1>
<h1>message:[[${message}]]</h1>

@ControllerAdvice
public class MyException  {
    @ResponseBody
    @ExceptionHandler(UserException.class)
    public Map<Object,String> userExc(Exception e){
        Map<Object,String> map = new HashMap<>();
        map.put("code","user.not.exist");
        map.put("message",e.getMessage());
        return map;
    }

}

@ExceptionHandler(UserException.class)
public String userExc(Exception e){
    Map<Object,String> map = new HashMap<>();
    map.put("code","user.not.exist");
    map.put("message",e.getMessage());
    return "forward:/error";
}

@ExceptionHandler(UserException.class)
public String userExc(Exception e, HttpServletRequest request){
    Map<Object,String> map = new HashMap<>();

    //传入我们自己的错误状态码  4xx  5xx
    //否则就不会进入定制错误页面的解析流程
    /**
     * Integer statusCode = (Integer) request
     .getAttribute("javax.servlet.error.status_code");
     */
    request.setAttribute("javax.servlet.error.status_code",400);

    //此时的数据是无法携带出去的
    map.put("code","user.not.exist");
    map.put("message",e.getMessage());
    return "forward:/error";
}