java注解-入參校驗（標注於單個參數上）

新增基類：

package com.yhsp.pay.common.enums.basenum;

public interface BaseEnum {

    String getKey();

    String getValue();

}

枚舉類實現基類：

package com.yhsp.pay.common.enums;

import com.yhsp.pay.common.enums.basenum.BaseEnum;

/**
 * @author guocz
 * @date 20211122
 * 業務平台枚舉
 */
public enum BizModeEnum implements BaseEnum {

    /**
     *
     */
    BAR_CODE("1", "默認"),
    APPLET_MALL("3", "小程序商城"),
    PAYMENT_CARD("4", "支付台牌");

    BizModeEnum(String key, String name) {
        this.key = key;
        this.name = name;
    }

    private String key;

    private String name;


    @Override
    public String getKey() {
        return key;
    }

    public String getName() {
        return name;
    }

    public String getKeyByName(String name) {
        for (BizModeEnum s : BizModeEnum.values()) {
            if (s.getName().equals(name)) {
                return s.getKey();
            }
        }
        return "";
    }

    public static String getNameByKey(String key) {
        for (BizModeEnum s : BizModeEnum.values()) {
            if (s.getKey().equals(key)) {
                return s.getName();
            }
        }
        return "";
    }

    @Override
    public String getValue() {
        return name;
    }

}

1、創建注解，添加屬性，采用@Constraint(validatedBy = {IfInEnumValidator.class})綁定注解實現類。

例：枚舉校驗

package com.yhsp.pay.model.aspect;

import com.yhsp.pay.common.enums.basenum.BaseEnum;
import com.yhsp.pay.model.aspect.impl.IfInEnumValidator;

import javax.validation.Constraint;
import javax.validation.Payload;
import java.lang.annotation.*;

/**
 * @author guocz
 * @date 20211123
 * 不為空判斷是否在枚舉中
 */
@Target({ElementType.METHOD, ElementType.FIELD, ElementType.ANNOTATION_TYPE, ElementType.CONSTRUCTOR})
@Retention(RetentionPolicy.RUNTIME)
@Constraint(validatedBy = {IfInEnumValidator.class})
public @interface IfInEnum {

    String message() default "枚舉值不正確";

    Class<? extends BaseEnum> enumClass();

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

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

2、創建注解實現類，實現ConstraintValidator<IfInEnum, String>接口，用於注解綁定該類。

package com.yhsp.pay.model.aspect.impl;

import com.yhsp.pay.common.enums.basenum.BaseEnum;
import com.yhsp.pay.model.aspect.IfInEnum;
import org.apache.commons.lang3.StringUtils;
import org.hibernate.validator.internal.engine.constraintvalidation.ConstraintValidatorContextImpl;

import javax.validation.ConstraintValidator;
import javax.validation.ConstraintValidatorContext;

/**
 * @author guocz
 * @date 20211123
 * 不為空判斷是否在枚舉中
 */
public class IfInEnumValidator implements ConstraintValidator<IfInEnum, String> {

    @Override
    public void initialize(IfInEnum constraintAnnotation) {
    }

    @Override
    public boolean isValid(String s, ConstraintValidatorContext constraintValidatorContext) {
        if (StringUtils.isBlank(s)) {
            return true;
        }

        Class c = (Class) ((ConstraintValidatorContextImpl) constraintValidatorContext).getConstraintDescriptor().getAttributes().get("enumClass");
        BaseEnum[] baseEnum = (BaseEnum[]) c.getEnumConstants();
        for (BaseEnum e : baseEnum) {
            if (e.getKey().equals(s)) {
                return true;
            }
        }

        return false;
    }

}