Java使用Validator进行Bean校验

• 工具类

package com.yjy.util;

import com.google.common.base.Preconditions;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
import com.yjy.exception.ParamException;
import org.apache.commons.collections.MapUtils;

import javax.validation.ConstraintViolation;
import javax.validation.Validation;
import javax.validation.Validator;
import javax.validation.ValidatorFactory;
import java.util.*;

public class BeanValidator {

    private static ValidatorFactory validatorFactory = Validation.buildDefaultValidatorFactory();

    public static <T> Map<String, String> validate(T t, Class... groups) {
        Validator validator = validatorFactory.getValidator();
        Set validateResult = validator.validate(t, groups);
        if (validateResult.isEmpty()) {
            return Collections.emptyMap();
        } else {
            LinkedHashMap errors = Maps.newLinkedHashMap();
            Iterator iterator = validateResult.iterator();
            while (iterator.hasNext()) {
                ConstraintViolation violation = (ConstraintViolation) iterator.next();
                errors.put(violation.getPropertyPath().toString(), violation.getMessage());
            }
            return errors;
        }
    }

    public static Map<String, String> validateList(Collection<?> collection) {
        Preconditions.checkNotNull(collection);
        Iterator iterator = collection.iterator();
        Map errors;
        do {
            if (!iterator.hasNext()) {
                return Collections.emptyMap();
            }
            Object object = iterator.next();
            errors = validate(object, new Class[0]);
        } while (errors.isEmpty());

        return errors;
    }

    public static Map<String, String> validateObject(Object first, Object... objects) {
        if (objects != null && objects.length > 0) {
            return validateList(Lists.asList(first, objects));
        } else {
            return validate(first, new Class[0]);
        }
    }

    public static void check(Object param) throws ParamException {
        Map<String, String> map = BeanValidator.validateObject(param);
        if (MapUtils.isNotEmpty(map)) {
            throw new ParamException(map.toString());
        }
    }
}

• 示例Bean

package com.yjy.param;

import lombok.Getter;
import lombok.Setter;
import org.hibernate.validator.constraints.Length;
import org.hibernate.validator.constraints.NotBlank;

import javax.validation.constraints.Max;
import javax.validation.constraints.Min;
import javax.validation.constraints.NotNull;

@Getter
@Setter
public class UserParam {

    private Integer id;

    @NotBlank(message = "用户名不可以为空")
    @Length(min = 1, max = 20, message = "用户名长度需要在20个字以内")
    private String username;

    @NotBlank(message = "电话不可以为空")
    @Length(min = 1, max = 13, message = "电话长度需要在13个字以内")
    private String telephone;

    @NotBlank(message = "邮箱不允许为空")
    @Length(min = 5, max = 50, message = "邮箱长度需要在50个字符以内")
    private String mail;

    @NotNull(message = "必须提供用户所在的部门")
    private Integer deptId;

    @NotNull(message = "必须指定用户的状态")
    @Min(value = 0, message = "用户状态不合法")
    @Max(value = 2, message = "用户状态不合法")
    private Integer status;

    @Length(min = 0, max = 200, message = "备注长度需要在200个字以内")
    private String remark = "";
}