自定义javax.validation校验枚举类

1、javax.validation中定义了大量的校验方法，能校验从页面接收到的数据；
2、但是对应对于枚举值的校验却没有，需要自己实现一个；
（例如：男女性别字段的值只能是1/2，状态值只能是1、2、3这三种情况）
3、创建过程：a.创建一个自定义注解【EnumValidation】；b.创建一个枚举类校验器【EnumValidator】

1、自定义的注解【EnumValidation】

package com.muscleape.annotation;

import com.muscleape.validator.EnumValidator;

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;

/**
 * To validate a enum's value is right or not .
 * <p>
 * example one, if a enum like
 * <code>
 * public enum Sex {
 * <p>
 * MALE, FEMALE, OTHER
 * }
 * </code>
 * can use the annotation as <code>@Enum(clazz = Sex.class)</code>, and param sex = 0;
 * Or use the annotation as <code>@Enum(clazz = Sex.class, method = "name")</code>,
 * and param sex = "MALE";
 * <p>
 * example two, if a enum like
 * <code>
 * public enum Role {
 * <p>
 * ADMIN(1, "ADMIN"),
 * TEST(2, "TEST"),
 * DEVELOP(3, "DEVELOP");
 * <p>
 * private int value;
 * private String desc;
 * <p>
 * Role(int value, String desc) {
 * this.value = value;
 * this.desc = desc;
 * }
 * <p>
 * public int getValue() {
 * return value;
 * }
 * <p>
 * public void setValue(int value) {
 * this.value = value;
 * }
 * <p>
 * public String getDesc() {
 * return desc;
 * }
 * <p>
 * public void setDesc(String desc) {
 * this.desc = desc;
 * }
 * }
 * </code>
 * can use the annotation as <code>@Enum(clazz = Role.class, method = "getValue")</code>,
 * and param role = 1; Or use the annotation as <code>@Enum(clazz = Role.class,
 * method = "getDesc")</code>,and param role = "ADMIN";
 *
 * @author Muscleape
 * @ClassName EnumValidate.java
 * @Description Controller入参对象中属性枚举项校验
 * @createTime 2020年03月18日 14:45:00
 */
@Documented
@Target({METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER, TYPE_USE})
@Retention(RUNTIME)
@Repeatable(EnumValidation.List.class)
@Constraint(validatedBy = {EnumValidator.class})
public @interface EnumValidation {
    String message() default "{*.validation.constraint.Enum.message}";

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

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

    /**
     * the enum's class-type
     *
     * @return Class
     */
    Class<?> clazz();

    /**
     * the method's name ,which used to validate the enum's value
     *
     * @return method's name
     */
    String method() default "ordinal";

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

2、自定义枚举类校验器【EnumValidator】

package com.muscleape.validator;

import com.muscleape.annotation.EnumValidation;

import javax.validation.ConstraintValidator;
import javax.validation.ConstraintValidatorContext;
import java.lang.reflect.Method;

/**
 * @author Muscleape
 * @ClassName EnumValidator.java
 * @Description Controller入参对象中属性枚举项校验
 * @createTime 2020年03月18日 14:51:00
 */
public class EnumValidator implements ConstraintValidator<EnumValidation, Object> {

    private EnumValidation annotation;

    /**
     * Initializes the validator in preparation for
     * {@link #isValid(Object, ConstraintValidatorContext)} calls.
     * The constraint annotation for a given constraint declaration
     * is passed.
     * <p>
     * This method is guaranteed to be called before any use of this instance for
     * validation.
     * <p>
     * The default implementation is a no-op.
     *
     * @param constraintAnnotation annotation instance for a given constraint declaration
     */
    @Override
    public void initialize(EnumValidation constraintAnnotation) {
        this.annotation = constraintAnnotation;
    }

    /**
     * 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(Object value, ConstraintValidatorContext context) {
        if (value == null) {
            return false;
        }

        Object[] objects = annotation.clazz().getEnumConstants();
        try {
            Method method = annotation.clazz().getMethod(annotation.method());
            for (Object o : objects) {
                if (value.equals(method.invoke(o))) {
                    return true;
                }
            }
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
        return false;
    }
}

3、 使用

package com.olayc.engine.ui.controller.manager.invoice;

import com.alibaba.fastjson.JSON;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Controller;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import javax.servlet.http.HttpServletResponse;

/**
 * Created by Weigang Wu on 2018/8/1.
 */
@Controller
@RequestMapping("muscleape/test")
public class EnumValidationController {

    /**
     * 发票冲红操作
     *
     * @return
     * @author Muscleape
     * @params
     * @updateTime 2020/3/18 13:47
     */
    @RequestMapping("testValidation")
    @ResponseBody
    public void testValidation(@Validated testValidation model) {
        return "";
    }

}

package com.muscleape.model;

import com.muscleape.annotation.EnumValidation;
import com.muscleape.enums.*;
import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;

import java.io.Serializable;

/**
 * @author Muscleape
 * @ClassName TestModel.java
 * @Description 
 * @createTime 2020年03月18日 13:52:00
 */
@Data
@Builder
@AllArgsConstructor
@NoArgsConstructor
public class TestModel implements Serializable {
    private static final long serialVersionUID = 6653149665302552059L;

    /**
     * 环境：0：开发；1：测试；2：UAT；3：生产
     */
    @EnumValidation(clazz = EnvironmentEnum.class, method = "getKey", message = "环境类型无效")
    private Integer invoiceTitleType;
}

package com.muscleape.enums;

import lombok.Getter;

/**
 * @author Muscleape
 * @ClassName EnvironmentEnum.java
 * @Description 环境类型
 * @createTime 2020年03月18日 15:01:00
 */
@Getter
public enum EnvironmentEnum {

    DEV(0, "开发"),
    TEST(1, "测试"),
    UAT(2, "UAT"),
    PROD(3, "生产");

    private final int key;
    private final String name;

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

}