SpringBoot 统一异常处理

1. 统一返回结果集

package com.liming.pojo;

import com.liming.exception.AppExceptionCodeMsg;
import lombok.Data;

/**
 * 全局统一返回结果类
 * @author 黎明
 * @date 2023/9/6 14:11
 * @version 1.0
 */
@Data
public class Result<T> {

    private Integer code; // 状态码
    private String msg; //返回消息
    private T data; //返回数据

    /**
     * 私有化构造方法，禁止在其它类创建对象
     */
    private Result(Integer code,String msg,T data){
        this.code = code;
        this.msg = msg;
        this.data = data;
    }

    // 不带自定义消息响应成功的方法
    public static <T> Result success(T data){
        Result resp = new Result(200, "success", data);
        return resp;
    }

    // 带自定义消息响应成功的方法
    public static <T> Result success(String msg, T data){
        Result resp = new Result(200,msg, data);
        return resp;
    }

    // 自定义异常返回的结果
    public static <T> Result error(AppExceptionCodeMsg appExceptionCodeMsg){
        Result resp = new Result(appExceptionCodeMsg.getCode(), appExceptionCodeMsg.getMsg(), null);
        return resp;
    }

    // 其他异常返回的结果
    public static <T> Result error(Integer code, String msg){
        Result resp = new Result(code,msg, null);
        return resp;
    }

}

2.业务相关异常枚举类

package com.liming.exception;

/**
 * 这个枚举类中定义的都是跟业务有关的异常
 * @author 黎明
 * @date 2023/9/6 14:31
 * @version 1.0
 */
public enum AppExceptionCodeMsg {

    // 业务操作错误定义
    INVALID_CODE(10000,"验证码无效"),
    USERNAME_NOT_EXISTS(10001,"用户名不存在"),
    USER_CREDIT_NOT_ENOUTH(10002,"用户积分不足"),
    ;

    // 错误码
    private Integer code ;
    // 错误消息
    private String msg ;

    AppExceptionCodeMsg(Integer code, String msg){
        this.code = code;
        this.msg = msg;
    }

    public Integer getCode() {
        return code;
    }

    public String getMsg() {
        return msg;
    }
}

3.自定义异常类

package com.liming.exception;

/**
 * 自定义异常类
 *
 * @author 黎明
 * @version 1.0
 * @date 2023/9/6 14:45
 */
public class AppException extends RuntimeException {

    // 错误码
    private Integer code;
    // 异常的消息描述
    private String msg;


    public AppException(AppExceptionCodeMsg appExceptionCodeMsg) {
        super();
        this.code = appExceptionCodeMsg.getCode();
        this.msg = appExceptionCodeMsg.getMsg();
    }

    public AppException(Integer code, String msg) {
        super();
        this.code = code;
        this.msg = msg;
    }

    public int getCode() {
        return code;
    }

    public String getMsg() {
        return msg;
    }
}

4.统一异常处理类

package com.liming.exception;

import com.liming.pojo.Result;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;

/**
 * 全局统一异常处理类
 *
 * @author 黎明
 * @version 1.0
 * @date 2023/9/6 14:42
 */
@ControllerAdvice
public class GlobalExceptionHandler {


    @ExceptionHandler(value = {Exception.class})
    @ResponseBody
    public <T> Result<T> exceptionHandler(Exception e) {
        // 这里先判断拦截到的Exception是不是我们自定义的异常类型
        if (e instanceof AppException) {
            AppException appException = (AppException) e;
            return Result.error(appException.getCode(), appException.getMsg());
        }

        // 如果拦截的异常不是我们自定义的异常(例如：数据库主键冲突)
        return Result.error(500, "服务器端异常");
    }
}

5.测试

controller

package com.liming.controller;

import com.liming.exception.AppException;
import com.liming.exception.AppExceptionCodeMsg;
import com.liming.pojo.Result;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.Arrays;
import java.util.List;

/**
 * @author 黎明
 * @version 1.0
 * @date 2023/9/6 14:53
 */
@Api(tags = "统一异常处理接口")
@RestController
public class UnifiedExceptionController {

    @ApiOperation("异常测试")
    @GetMapping("/demo")
    public Result<String> demo1(String name) {
        if ("ok".equals(name)) {
            return Result.success("succ");
        }
        if ("err".equals(name)) {
            //抛自定义业务相关的异常
            throw new AppException(AppExceptionCodeMsg.USERNAME_NOT_EXISTS);
        }
        if ("errCode".equals(name)) {
            //抛自定义业务相关的异常
            throw new AppException(AppExceptionCodeMsg.INVALID_CODE);
        }
        if("notenough".equals(name)){
            //抛自定义业务相关的异常
            throw new AppException(AppExceptionCodeMsg.USER_CREDIT_NOT_ENOUTH);
        }
        if ("0".equals(name)) {
            // 抛出其他异常
            int i = 1 / 0;
        }
        return Result.success("操作成功");
    }

    @GetMapping("list")
    public Result<List> list(){
        List<String> list = Arrays.asList("zhangsan","lisi","wangwu");

        return Result.success(list);
    }
}

结果展示