Springboot中HttpMessageNotReadableException异常处理冲突求助

冲突原因 #

你的异常处理类继承了ResponseEntityExceptionHandler，父类中已存在handleException(Exception, WebRequest)方法；而你自定义的handleException(Exception)方法在匹配HttpMessageNotReadableException时，Spring无法判断应调用哪个方法，从而触发映射歧义。

解决方案 #

方案一：修改自定义方法参数为具体异常类

将方法参数从泛型的Exception改为目标异常类HttpMessageNotReadableException，让匹配逻辑更精确，避免和父类方法冲突：

package com.proj.my.advice;

import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.http.converter.HttpMessageNotReadableException;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;
import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler;

import lombok.extern.slf4j.Slf4j;

@RestControllerAdvice
@Slf4j
public class ApplicationExceptionHandler extends ResponseEntityExceptionHandler {
   
   @ExceptionHandler(HttpMessageNotReadableException.class)
   public ResponseEntity<String> handleHttpMessageNotReadable(HttpMessageNotReadableException e){
       log.error("请求参数解析失败：{}", e.getMessage());
       return new ResponseEntity<>("价格参数格式错误，请输入有效的数字", HttpStatus.BAD_REQUEST);
   }
}

方案二：重写父类的专属异常处理方法

ResponseEntityExceptionHandler本身提供了处理HttpMessageNotReadableException的专用方法handleHttpMessageNotReadable，直接重写该方法即可，无需额外添加@ExceptionHandler注解：

package com.proj.my.advice;

import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.HttpStatusCode;
import org.springframework.http.ResponseEntity;
import org.springframework.http.converter.HttpMessageNotReadableException;
import org.springframework.web.bind.annotation.RestControllerAdvice;
import org.springframework.web.context.request.WebRequest;
import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler;

import lombok.extern.slf4j.Slf4j;

@RestControllerAdvice
@Slf4j
public class ApplicationExceptionHandler extends ResponseEntityExceptionHandler {

    @Override
    protected ResponseEntity<Object> handleHttpMessageNotReadable(HttpMessageNotReadableException ex, HttpHeaders headers, HttpStatusCode status, WebRequest request) {
        log.error("请求参数解析失败：{}", ex.getMessage());
        return new ResponseEntity<>("价格参数格式错误，请输入有效的数字", HttpStatus.BAD_REQUEST);
    }
}

方案三：移除父类继承关系

如果不需要父类提供的其他默认异常处理逻辑，可以直接去掉ResponseEntityExceptionHandler继承，仅保留自定义异常处理：

package com.proj.my.advice;

import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.http.converter.HttpMessageNotReadableException;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;

import lombok.extern.slf4j.Slf4j;

@RestControllerAdvice
@Slf4j
public class ApplicationExceptionHandler {
   
   @ExceptionHandler(HttpMessageNotReadableException.class)
   public ResponseEntity<String> handleHttpMessageNotReadable(HttpMessageNotReadableException e){
       log.error("请求参数解析失败：{}", e.getMessage());
       return new ResponseEntity<>("价格参数格式错误，请输入有效的数字", HttpStatus.BAD_REQUEST);
   }
}

内容的提问来源于stack exchange，提问作者Dadinho2000