自定义抛出异常

可以先定义一个枚举类

import lombok.AllArgsConstructor;
import lombok.Getter;
import lombok.NoArgsConstructor;

@Getter
@NoArgsConstructor
@AllArgsConstructor
public enum ExceptionEnum {

    PRICE_CANNOT_BE_NULL(400,"价格不能为空！"),
    CATEGORY_NOT_FOUND(404,"商品分类没查到"),
    ;
    private int code;
    private String msg;
}

然后定义一个异常继承EuntimeException

import lombok.AllArgsConstructor;
import lombok.Getter;
import lombok.NoArgsConstructor;

@NoArgsConstructor
@AllArgsConstructor
@Getter
public class LyException extends RuntimeException{

    private ExceptionEnum exceptionEnum;
}

然后在controller层做拦截

import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;

@ControllerAdvice
public class CommonExceptionHandler {

    @ExceptionHandler(RuntimeException.class)
    public ResponseEntity<ExceptionResult> handleException(LyException e){
        ExceptionEnum em = e.getExceptionEnum();
        return ResponseEntity.status(em.getCode()).body(new ExceptionResult(e.getExceptionEnum()));
    }
}

即可

也可以加上下行参数实体

import lombok.Data;

@Data
public class ExceptionResult {
    private int status;
    private String message;
    private Long timestamp;

    public ExceptionResult(ExceptionEnum em){
        this.status = em.getCode();
        this.message = em.getMsg();
        this.timestamp = System.currentTimeMillis();
    }
}