Spring在实体类里面约束及控制器使用

需要的包

  <dependency>
          <groupId>commons-lang</groupId>
          <artifactId>commons-lang</artifactId>
          <version>2.6</version>
      </dependency>
      <dependency>
          <groupId>commons-io</groupId>
          <artifactId>commons-io</artifactId>
          <version>2.4</version>
      </dependency>
      <dependency>
          <groupId>commons-fileupload</groupId>
          <artifactId>commons-fileupload</artifactId>
          <version>1.2.2</version>
      </dependency>

      <dependency>
          <groupId>org.hibernate.validator</groupId>
          <artifactId>hibernate-validator</artifactId>
          <version>6.1.5.Final</version>
      </dependency>

常用参数

代码演示

实体类

@NotEmpty(message = "名字不能为空")
    private String name;

@Min(message = "年龄必须大于等于18", value = 18)
@Max(message = "年龄必须小于等于70", value = 70)
@NotNull(message = "年龄不能为空")
    private Integer age;

控制器

/*
@valid是校验这些添加注解的属性，如：校验从前端传入的参数是否合法
Spring验证完@valid侯，会将任何错误放在BindingResult，你就可以判断它了
*/

    public String update(@Valid Person person,BindingResult result) {
        if(result.hasErrors()){
            System.out.println("输入的内容不合法");
            return "login";
        }
        return "index";
    }