springboot实现Validator校验-工具盒子

一个优秀的后端，是不会相信任何传入的参数的

要做到这一点，以前我们是写大量的判断代码来验证数据的格式

在开发中，我们实际不这么干，我们使用Hibernate Validator来进行参数校验

它实现了JSR 303规范，使我们的代码的健壮性大大提高

先列出一些常用注解

| 约束注解 | 详细信息 | |-------------------------------|------------------------------| | @Null | 被注释的元素必须为 null | | @NotNull | 被注释的元素必须不为 null | | @AssertTrue | 被注释的元素必须为 true | | @AssertFalse | 被注释的元素必须为 false | | @Min(value) | 被注释的元素必须是一个数字，其值必须大于等于指定的最小值 | | @Max(value) | 被注释的元素必须是一个数字，其值必须小于等于指定的最大值 | | @DecimalMin(value) | 被注释的元素必须是一个数字，其值必须大于等于指定的最小值 | | @DecimalMax(value) | 被注释的元素必须是一个数字，其值必须小于等于指定的最大值 | | @Size(max, min) | 被注释的元素的大小必须在指定的范围内 | | @Digits (integer, fraction) | 被注释的元素必须是一个数字，其值必须在可接受的范围内 | | @Past | 被注释的元素必须是一个过去的日期 | | @Future | 被注释的元素必须是一个将来的日期 | | @Pattern(value) | 被注释的元素必须符合指定的正则表达式 | | @Email | 被注释的元素必须是电子邮箱地址 | | @Length | 被注释的字符串的大小必须在指定的范围内 | | @NotEmpty | 被注释的字符串的必须非空 | | @Range | 被注释的元素必须在合适的范围内 |

使用方式也很简单，springboot引入依赖就可以使用了

|-----------------|------------------------------------------------------------------------------------------------------------------------------------------------| | 1 2 3 4 | hljs xml <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-validation</artifactId> </dependency> |

公司常用的方式是用注解方式，关于另一种方式和spring实现方式之后的博客会写

我们之前写的springboot项目中用的aop方式实现参数校验，这里我先给他废弃掉

然后校验已经关闭了

我们首先去给接参的实体类加上注解

然后在接口上加@Valid注解

这个时候我们启动项目发现，已经成功校验了，如果我们参数格式错误，会抛出一个MethodArgumentNotValidException

这时候我们就只需要在全局异常处理器进行捕获，返回提示就可以了，全局异常处理器怎么写呢？之后的博客也会提到，在此之前可以试着自己动手写一下

如果提供的原生的注解不满足我们的需要，我们可以自定义

先点进去注解内部

我们照着写一个

|------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 | hljs java package com.ruben.validator; import javax.validation.Constraint; import javax.validation.Payload; import javax.validation.ReportAsSingleViolation; import javax.validation.constraints.NotBlank; import javax.validation.constraints.Pattern; import java.lang.annotation.Documented; import java.lang.annotation.Retention; import java.lang.annotation.Target; import static java.lang.annotation.ElementType.*; import static java.lang.annotation.RetentionPolicy.RUNTIME; /** * @ClassName: Username * @Description: * @Date: 2020/8/15 15:39 * * * @author: achao<achao1441470436 @ gmail.com> * @version: 1.0 * @since: JDK 1.8 */ @NotBlank @Documented @Pattern(regexp = "^[A-Za-z0-9]{8,16}$") @Retention(RUNTIME) @Constraint(validatedBy = {}) @ReportAsSingleViolation @Target({METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER, TYPE_USE}) public @interface Username { String message() default "用户名必须满足8-16位的英文和数字"; Class<?>[] groups() default {}; Class<? extends Payload>[] payload() default {}; } |

换成我们的Username

可以看到生效了

当然，我这里是做了全局异常处理才能达到这样的效果的，不然还是控制台抛异常。。。

这时候可能有小伙伴问了，如果我想自定义规则怎么办呢？

那么我们密码就来实现一波自定义规则

比如整个简单的密码应在6-20字符之间，其中小写字母、大写字母、数字和字符必须有三种以上，不能出现连续三个重复的字符,且不能为汉字

首先创建一个校验类，继承ConstraintValidator<?,?>

然后重写方法写好判断，return一个boolean

|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 | hljs java package com.ruben.validator; import javax.validation.ConstraintValidator; import javax.validation.ConstraintValidatorContext; import java.util.regex.Pattern; /** * @ClassName: PasswordValidator * @Description: * @Date: 2020/8/15 16:44 * * * @author: achao<achao1441470436 @ gmail.com> * @version: 1.0 * @since: JDK 1.8 */ public class PasswordValidator implements ConstraintValidator<Password, String> { /** * Implements the validation logic. * The state of {@code value} must not be altered. * <p> * This method can be accessed concurrently, thread-safety must be ensured * by the implementation. * * @param value object to validate * @param context context in which the constraint is evaluated * @return {@code false} if {@code value} does not pass the constraint */ @Override public boolean isValid(String value, ConstraintValidatorContext context) { if (value.length() <= 6 || value.length() >= 20) { return false; } if (value.contains(" ")) { return false; } boolean hasUpperCase = false; boolean hasLowerCase = false; boolean hasNumber = false; boolean hasCharacter = false; String upperCaseRegexp = "^[A-Z]+$"; String lowerCaseRegexp = "^[a-z]+$"; String numberRegexp = "^[0-9]*$"; Pattern upperCasePattern = Pattern.compile(upperCaseRegexp); Pattern lowerCasePattern = Pattern.compile(lowerCaseRegexp); Pattern numberPattern = Pattern.compile(numberRegexp); int countRepeat = 0; char[] chars = value.toCharArray(); for (int i = 0; i < chars.length; i++) { if (i != chars.length - 1 && chars[i] == chars[i + 1]) { countRepeat++; } if (countRepeat == 3) { return false; } String singleChar = String.valueOf(chars[i]); String chineseRegexp = "^[\\u4e00-\\u9fa5]*$"; Pattern chinesePattern = Pattern.compile(chineseRegexp); if (chinesePattern.matcher(singleChar).matches()) { return false; } if (upperCasePattern.matcher(singleChar).matches()) { hasUpperCase = true; } else if (lowerCasePattern.matcher(singleChar).matches()) { hasLowerCase = true; } else if (numberPattern.matcher(singleChar).matches()) { hasNumber = true; } else { hasCharacter = true; } } int countMatches = 0; if (hasUpperCase) { countMatches++; } if (hasLowerCase) { countMatches++; } if (hasNumber) { countMatches++; } if (hasCharacter) { countMatches++; } return countMatches >= 3; } } |

然后再自定义我们的注解

|------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 | hljs java package com.ruben.validator; import javax.validation.Constraint; import javax.validation.Payload; import javax.validation.ReportAsSingleViolation; import javax.validation.constraints.NotBlank; import java.lang.annotation.Documented; import java.lang.annotation.Retention; import java.lang.annotation.Target; import static java.lang.annotation.ElementType.*; import static java.lang.annotation.RetentionPolicy.RUNTIME; /** * @ClassName: Password * @Description: * @Date: 2020/8/15 16:36 * * * @author: achao<achao1441470436 @ gmail.com> * @version: 1.0 * @since: JDK 1.8 */ @NotBlank @Documented @Retention(RUNTIME) @Constraint(validatedBy = PasswordValidator.class) @ReportAsSingleViolation @Target({METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER, TYPE_USE}) public @interface Password { String message() default "密码应在6-20字符之间，其中小写字母、大写字母、数字和字符必须有三种以上，不能出现连续三个重复的字符,且不能为汉字"; Class<?>[] groups() default {}; Class<? extends Payload>[] payload() default {}; } |

然后在我们的参数上加上我们自定义的注解