SpringBoot参数校验之@Valid的使用详解-Java开发

这篇文章主要通过示例为大家详细介绍一下介绍了SpringBoot参数校验中@Valid的使用方法，文中的示例代码讲解详细，需要的可以参考一下

简介

说明

本文用示例说明SpringBoot的@Valid的用法。

依赖

<dependency>
    <groupId>org.hibernate.validator</groupId>
    <artifactId>hibernate-validator</artifactId>
</dependency>

代码

Controller

package com.example.demo.simple.controller;
 
import com.example.demo.simple.entity.User;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import org.springframework.validation.BindingResult;
import org.springframework.validation.ObjectError;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
 
import javax.validation.Valid;
import java.util.List;
 
@Api(tags = "不分组")
@RestController
@RequestMapping("valid")
public class ValidController {
 
    @ApiOperation("正常用法")
    @GetMapping("normal")
    public User normal(@Valid User user) {
        return user;
    }
 
    @ApiOperation("获得BindingResult")
    @GetMapping("bindingResult")
    public User bindingResult(@Valid User user, BindingResult bindingResult) {
        if (bindingResult.hasErrors()){
            List<ObjectError> list = bindingResult.getAllErrors();
            for (ObjectError objectError : list) {
                System.out.println(objectError.getDefaultMessage());
            }
            //System.out.println(bindingResult.getFieldError().getDefaultMessage());
        }
 
        return user;
    }
 
}

Entity

User类

package com.example.demo.simple.entity;
 
import lombok.Data;
 
import javax.validation.Valid;
import javax.validation.constraints.NotBlank;
import javax.validation.constraints.NotEmpty;
import javax.validation.constraints.NotNull;
import java.util.List;
 
@Data
public class User {
    @NotBlank(message = "名字不能为空")
    private String name;
 
    private Integer age;
 
    @NotBlank(message = "密码不能为空")
    private String password;
 
    @NotEmpty(message = "分数不能为空")
    private List<Integer> scoreArray;
 
    @Valid
    @NotNull(message = "账户不能为null")
    private Account account;
}

Account类

package com.example.demo.simple.entity;
 
import lombok.Data;
 
import javax.validation.constraints.NotBlank;
import javax.validation.constraints.NotEmpty;
import java.io.Serializable;
 
@Data
public class Account {
    @NotBlank(message = "电话号码不能为空")
    private String phoneNumber;
 
    private String[] emails;
}

测试

本文为了展示后端错误，直接用postman来进行请求。

实际上，如果用了knife4j这个接口工具，它能自动识别是否为空的注解，并在前端进行控制。如果不能为空，则前端直接显示为红色的框。

测试1：缺少字段

postman访问：http://localhost:8080/valid/normal

postman访问结果：

后端结果：

2021-12-22 15:32:20.032 WARN 94176 --- [nio-8080-exec-5] .w.s.m.s.DefaultHandlerExceptionResolver : Resolved [org.springframework.validation.BindException: org.springframework.validation.BeanPropertyBindingResult: 3 errors
Field error in object 'user' on field 'account': rejected value [null]; codes [NotNull.user.account,NotNull.account,NotNull.com.example.demo.simple.entity.Account,NotNull]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [user.account,account]; arguments []; default message [account]]; default message [账户不能为null]
Field error in object 'user' on field 'password': rejected value [null]; codes [NotBlank.user.password,NotBlank.password,NotBlank.java.lang.String,NotBlank]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [user.password,password]; arguments []; default message [password]]; default message [密码不能为空]
Field error in object 'user' on field 'scoreArray': rejected value [null]; codes [NotEmpty.user.scoreArray,NotEmpty.scoreArray,NotEmpty.java.util.List,NotEmpty]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [user.scoreArray,scoreArray]; arguments []; default message [scoreArray]]; default message [分数不能为空]]