SpringBoot - 优雅的实现【自定义参数校验】高级进阶

文章目录

• ​​Pre​​
• ​​概述​​
• ​​三部曲​​

• ​​Step1 搞自定义注解​​
• ​​Step2 搞校验逻辑​​
• ​​Step3 使用​​
• ​​Step4 验证​​

• ​​附 int 类型的判断​​
• ​​源码​​

Pre

SpringBoot - 优雅的实现【参数校验】高级进阶

概述

接上文， Spring Validation 提供的注解基本上够用，但是复杂的校验，我们还是需要自己定义注解来实现自动校验。

举个例子： 实体类中的sex性别属性 , 只能输入 M 、 F 这2个枚举值

三部曲

Step1 搞自定义注解

package com.artisan.customvalidator;


import javax.validation.Constraint;
import javax.validation.Payload;
import java.lang.annotation.Documented;
import java.lang.annotation.Repeatable;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;

import static java.lang.annotation.ElementType.*;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

/**
 * @author 小工匠
 * @version 1.0
 * @mark: show me the code , change the world
 */

@Target({METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER, TYPE_USE})
@Retention(RUNTIME)
@Repeatable(EnumString.List.class)
@Documented
@Constraint(validatedBy = EnumStringValidator.class)//标明由哪个类执行校验逻辑
public @interface EnumString {

    String message() default "value not in enum values.";

    Class<?>[] groups() default {};

    Class<? extends Payload>[] payload() default {};

    /**
     * @return date must in this value array
     */
    String[] value();

    /**
     * Defines several {@link EnumString} annotations on the same element.
     *
     * @see EnumString
     */
    @Target({METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER, TYPE_USE})
    @Retention(RUNTIME)
    @Documented
    @interface List {

        EnumString[] value();
    }
}

Step2 搞校验逻辑

package com.artisan.customvalidator;

import lombok.extern.slf4j.Slf4j;

import javax.validation.ConstraintValidator;
import javax.validation.ConstraintValidatorContext;
import java.util.Arrays;
import java.util.List;

/**
 * @author 小工匠
 * @version 1.0
 * @mark: show me the code , change the world
 */
@Slf4j
public class EnumStringValidator implements ConstraintValidator<EnumString, String> {
    private List<String> enumStringList;

    @Override
    public void initialize(EnumString constraintAnnotation) {
        log.info("EnumStringValidator initialize.....");
        enumStringList = Arrays.asList(constraintAnnotation.value());
    }

    @Override
    public boolean isValid(String value, ConstraintValidatorContext context) {
        if (value == null) {
            return true;
        }
        return enumStringList.contains(value);
    }
}

Step3 使用

在字段上增加注解

Step4 验证

附 int 类型的判断

package com.artisan.customvalidator;

import javax.validation.Constraint;
import javax.validation.Payload;
import java.lang.annotation.Documented;
import java.lang.annotation.Repeatable;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;

import static java.lang.annotation.ElementType.*;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

/**
 * @author 小工匠
 * @version 1.0
 * @Des 扩展int枚举校验
 * @mark: show me the code , change the world
 */
@Target({METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER, TYPE_USE})
@Retention(RUNTIME)
@Repeatable(EnumInteger.List.class)
@Documented
@Constraint(validatedBy = EnumNumberValidator.class)
public @interface EnumInteger {

    String message() default "value not in enum values.";

    Class<?>[] groups() default {};

    Class<? extends Payload>[] payload() default {};

    /**
     * @return date must in this value array
     */
    int[] value();

    /**
     * Defines several {@link EnumInteger} annotations on the same element.
     *
     * @see EnumInteger
     */
    @Target({METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER, TYPE_USE})
    @Retention(RUNTIME)
    @Documented
    @interface List {
        EnumInteger[] value();
    }
}

package com.artisan.customvalidator;

import javax.validation.ConstraintValidator;
import javax.validation.ConstraintValidatorContext;
import java.util.ArrayList;
import java.util.List;

/**
 * @author 小工匠
 * @version 1.0
 * @mark: show me the code , change the world
 */
public class EnumNumberValidator implements ConstraintValidator<EnumInteger, Number> {
    private List<Integer> enumStringList;

    @Override
    public void initialize(EnumInteger constraintAnnotation) {
        enumStringList = new ArrayList<>();
        int[] values = constraintAnnotation.value();
        for (int value : values) {
            enumStringList.add(value);
        }
    }

    @Override
    public boolean isValid(Number value, ConstraintValidatorContext context) {
        if (value == null) {
            return true;
        }
        return enumStringList.contains(value.intValue());
    }
}

源码

​​https://github.com/yangshangwei/boot2​​