JAVA字段校验(validation)

在开发业务时，不可避免的需要处理一些校验， 如果是写if-else这种代码去校验， 那会有一大段这样的代码。不过还好有个校验插件：javax.validation.validation-api，不过一般会引用hibernate的校验组件：org.hibernate.hibernate-validator， 它已经引用了validation-api组件。

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基础校验类型

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JSR303 是一套JavaBean参数校验的标准，它定义了很多常用的校验注解，我们可以直接将这些注解加在我们JavaBean的属性上面，就可以在需要校验的时候进行校验了。注解如下：

Hibernate validator 在JSR303的基础上对校验注解进行了扩展，扩展注解如下：

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写个DEMO看看

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校验工具类:ValidatorUtils

import javax.validation.ConstraintViolation;
import javax.validation.Validation;
import javax.validation.Validator;
import javax.validation.groups.Default;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.stream.Collectors;

/**
 * Created by saleson on 2017/10/13.
 */
public class ValidatorUtils {


    private static Validator validator = Validation.buildDefaultValidatorFactory()
            .getValidator();


    public static <T> Map<String, String> validate(T obj) {
        Map<String, StringBuilder> errorMap = new HashMap<>();
        Set<ConstraintViolation<T>> set = validator.validate(obj, Default.class);
        if (set != null && set.size() > 0) {
            String property = null;
            for (ConstraintViolation<T> cv : set) {
                //这里循环获取错误信息，可以自定义格式
                property = cv.getPropertyPath().toString();
                if (errorMap.get(property) != null) {
                    errorMap.get(property).append("," + cv.getMessage());
                } else {
                    StringBuilder sb = new StringBuilder();
                    sb.append(cv.getMessage());
                    errorMap.put(property, sb);
                }
            }
        }
        return errorMap.entrySet().stream().collect(Collectors.toMap(k -> k.getKey(), v -> v.getValue().toString()));
    }
}

DemoBean:

import com.fm.core.exceptions.ApiException;
import org.hibernate.validator.constraints.NotEmpty;
import com.fm.framework.api.ApiResultHelper;
import com.fm.framework.json.Json;
import com.fm.framework.utils.StringUtils;
import com.fm.grantauth.domain.ValidateResult;
import com.fm.grantauth.domain.dto.AuthorizationApplyDTO;
import com.fm.grantauth.utils.ValidatorUtils;
import org.junit.Test;

import javax.validation.Valid;
import java.util.Map;

/**
 * Created by saleson on 2017/10/12.
 */
public class DataAuthValidator  {
private static final Logger log = LoggerFactory.getLogger(DataAuthValidator.class);

    @Override
    public ValidateResult validate(AuthorizationApplyDTO applyDTO) {
        String json = applyDTO.getContractParams();
        if (StringUtils.isEmpty(json)) {
            throw new ApiException(ApiResultHelper.newParameterEmpty("contractParams字段不能为空"));
        }
        DataAuthContractParams params = Json.parseObject(json, DataAuthContractParams.class);
        Map<String, String> validMap = ValidatorUtils.validate(params);
        if (!validMap.isEmpty()) {
            log.warn(validMap.toString());
            throw new ApiException(ApiResultHelper.newBusinessError(lackFieldMessage(validMap.keySet().toArray(new String[0]))));
        }
        return new ValidateResult(true);
    }


    public static class DataAuthContractParams {
        @NotEmpty
        private String businessName;
        @NotEmpty
        private String dataProvider;
        @NotEmpty
        private String personalDataName;
        @NotEmpty
        private String dataDemander;

        public String getBusinessName() {
            return businessName;
        }

        public void setBusinessName(String businessName) {
            this.businessName = businessName;
        }

        public String getDataProvider() {
            return dataProvider;
        }

        public void setDataProvider(String dataProvider) {
            this.dataProvider = dataProvider;
        }

        public String getPersonalDataName() {
            return personalDataName;
        }

        public void setPersonalDataName(String personalDataName) {
            this.personalDataName = personalDataName;
        }

        public String getDataDemander() {
            return dataDemander;
        }

        public void setDataDemander(String dataDemander) {
            this.dataDemander = dataDemander;
        }

    }



    @Test
    public void test() {
        AuthorizationApplyDTO applyDTO = new AuthorizationApplyDTO();
        DataAuthContractParams params = new DataAuthContractParams();
        params.setBusinessName("f");
        params.setDataDemander("f");
        params.setDataProvider("");
        params.setPersonalDataName("");

        applyDTO.setContractParams(Json.toJSONString(params));
        ValidateResult result = new DataAuthValidator().validate(applyDTO);
        System.out.println(Json.toJSONString(result));
        assert result.isSeccess();
    }
}

运行结果:

[main] WARN com.fm.grantauth.module.authorization.contact.DataAuthValidator - {dataProvider=不能为空, personalDataName=不能为空}

com.fm.core.exceptions.ApiException: 参数contractParams中缺少字段:dataProvider, personalDataName

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自定义校验规则(Validator)

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自定义注解:

package com.fm.core.validation;

import com.fm.core.validation.validator.NotEmptyValidator;

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

import static java.lang.annotation.ElementType.ANNOTATION_TYPE;
import static java.lang.annotation.ElementType.CONSTRUCTOR;
import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.PARAMETER;

/**
 * Created by saleson on 2017/5/31.
 */
@Retention(RetentionPolicy.RUNTIME)
@Target({METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER})
@Documented
@Constraint(validatedBy = {NotEmptyValidator.class})
public @interface NotEmpty {

    String message() default "参数不能为null或空字符串";

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

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

校验器(validator):

package com.fm.core.validation.validator;

import com.fm.core.validation.NotEmpty;
import com.fm.framework.utils.StringUtils;
import org.apache.commons.collections.MapUtils;

import javax.validation.ConstraintValidatorContext;
import java.lang.reflect.Array;
import java.util.Collection;
import java.util.Map;

/**
 * Created by saleson on 2017/5/27.
 */
public class NotEmptyValidator extends AbstractValidator<NotEmpty, Object> {

    @Override
    protected boolean validNull(ConstraintValidatorContext context) {
        return false;
    }

    @Override
    protected boolean valid(Object value, ConstraintValidatorContext context) {
        if (value instanceof String) {
            return StringUtils.isNotEmpty(value.toString());
        } else if (value instanceof Collection) {
            return !org.springframework.util.CollectionUtils.isEmpty((Collection) value);
        } else if (value instanceof Map) {
            return MapUtils.isNotEmpty((Map) value);
        } else if (value.getClass().isArray()) {
            return Array.getLength(value) > 0;
        }
        return true;
    }


}

将上个demo中引用的org.hibernate.validator.constraints.NotEmpty改为com.fm.core.validation.NotEmpty即可。
运行结果：

WARN com.fm.grantauth.module.authorization.contact.DataAuthValidator - {dataProvider=参数不能为null或空字符串, personalDataName=参数不能为null或空字符串}

com.fm.core.exceptions.ApiException: 参数contractParams中缺少字段:dataProvider, personalDataName

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级联校验

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校验的对象中包含另一个需要校验的对象时，则可以使用@javax.validation.Valid

import com.fm.core.exceptions.ApiException;
import com.fm.core.validation.NotEmpty;
import com.fm.framework.api.ApiResultHelper;
import com.fm.framework.json.Json;
import com.fm.framework.utils.StringUtils;
import com.fm.grantauth.domain.ValidateResult;
import com.fm.grantauth.domain.dto.AuthorizationApplyDTO;
import com.fm.grantauth.utils.ValidatorUtils;
import org.junit.Test;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.validation.Valid;
import java.util.Map;

/**
 * Created by saleson on 2017/10/12.
 */
public class DataAuthValidator implements ContractParamsValidator {
    private static final Logger log = LoggerFactory.getLogger(DataAuthValidator.class);

    @Override
    public ValidateResult validate(AuthorizationApplyDTO applyDTO) {
        String json = applyDTO.getContractParams();
        if (StringUtils.isEmpty(json)) {
            throw new ApiException(ApiResultHelper.newParameterEmpty("contractParams字段不能为空"));
        }
        DataAuthContractParams params = Json.parseObject(json, DataAuthContractParams.class);
        Map<String, String> validMap = ValidatorUtils.validate(params);
        if (!validMap.isEmpty()) {
            log.warn(validMap.toString());
            throw new ApiException(ApiResultHelper.newBusinessError(lackFieldMessage(validMap.keySet().toArray(new String[0]))));
        }
        return new ValidateResult(true);
    }


    public static class DataAuthContractParams {
        @NotEmpty
        private String businessName;
        @NotEmpty
        private String dataProvider;
        @NotEmpty
        private String personalDataName;
        @NotEmpty
        private String dataDemander;
        //        @NotEmpty
        @Valid
        private Re r;

        public String getBusinessName() {
            return businessName;
        }

        public void setBusinessName(String businessName) {
            this.businessName = businessName;
        }

        public String getDataProvider() {
            return dataProvider;
        }

        public void setDataProvider(String dataProvider) {
            this.dataProvider = dataProvider;
        }

        public String getPersonalDataName() {
            return personalDataName;
        }

        public void setPersonalDataName(String personalDataName) {
            this.personalDataName = personalDataName;
        }

        public String getDataDemander() {
            return dataDemander;
        }

        public void setDataDemander(String dataDemander) {
            this.dataDemander = dataDemander;
        }

        public Re getR() {
            return r;
        }

        public void setR(Re r) {
            this.r = r;
        }
    }


    public static class Re {

        @NotEmpty
        private String d;

        public String getD() {
            return d;
        }

        public void setD(String d) {
            this.d = d;
        }
    }

    @Test
    public void test() {
        AuthorizationApplyDTO applyDTO = new AuthorizationApplyDTO();
        DataAuthContractParams params = new DataAuthContractParams();
        params.setBusinessName("f");
        params.setDataDemander("f");
        params.setDataProvider("");
        params.setPersonalDataName("");
        Re r = new Re();
        params.setR(r);

        applyDTO.setContractParams(Json.toJSONString(params));
        ValidateResult result = new DataAuthValidator().validate(applyDTO);
        System.out.println(Json.toJSONString(result));
        assert result.isSeccess();
    }
}

运行结果：

WARN com.fm.grantauth.module.authorization.contact.DataAuthValidator - {r.d=参数不能为null或空字符串, dataProvider=参数不能为null或空字符串, personalDataName=参数不能为null或空字符串}

com.fm.core.exceptions.ApiException: 参数contractParams中缺少字段:r.d, dataProvider, personalDataName

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分组校验

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对同一个Model，我们在增加和修改时对参数的校验也是不一样的，这个时候我们就需要定义分组验证。
com.fm.core.validation.NotEmpty#groups()就是用于分组校验的

添加两个用于分组校验的接口：

public static interface GroupFirst {

}

public static interface GroupSecond {

}

校验改成:

    public static class DataAuthContractParams {
        @NotEmpty
        private String businessName;
        @NotEmpty
        private String dataProvider;
        @NotEmpty(groups = GroupFirst.class)
        private String personalDataName;
        @NotEmpty(groups = {GroupFirst.class, GroupSecond.class})
        private String dataDemander;
        //        @NotEmpty
        @Valid
        private Re r;

        public String getBusinessName() {
            return businessName;
        }

        public void setBusinessName(String businessName) {
            this.businessName = businessName;
        }

        public String getDataProvider() {
            return dataProvider;
        }

        public void setDataProvider(String dataProvider) {
            this.dataProvider = dataProvider;
        }

        public String getPersonalDataName() {
            return personalDataName;
        }

        public void setPersonalDataName(String personalDataName) {
            this.personalDataName = personalDataName;
        }

        public String getDataDemander() {
            return dataDemander;
        }

        public void setDataDemander(String dataDemander) {
            this.dataDemander = dataDemander;
        }

        public Re getR() {
            return r;
        }

        public void setR(Re r) {
            this.r = r;
        }
    }


    public static class Re {

        @NotEmpty(groups = GroupSecond.class)
        private String d;

        public String getD() {
            return d;
        }

        public void setD(String d) {
            this.d = d;
        }
    }

修改ValidatorUtils

package com.fm.grantauth.utils;

import javax.validation.ConstraintViolation;
import javax.validation.Validation;
import javax.validation.Validator;
import javax.validation.groups.Default;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.stream.Collectors;

/**
 * Created by saleson on 2017/10/13.
 */
public class ValidatorUtils {


    private static Validator validator = Validation.buildDefaultValidatorFactory()
            .getValidator();


    public static <T> Map<String, String> validate(T obj) {
        Set<ConstraintViolation<T>> set = validator.validate(obj, Default.class);
        return convertErrorMap(set);
    }


    public static <T> Map<String, String> validate(T obj, Class<?>... groups) {
        Set<ConstraintViolation<T>> set = validator.validate(obj, groups);
        return convertErrorMap(set);
    }


    private static <T> Map<String, String> convertErrorMap(Set<ConstraintViolation<T>> set) {
        Map<String, StringBuilder> errorMap = new HashMap<>();
        if (set != null && set.size() > 0) {
            String property = null;
            for (ConstraintViolation<T> cv : set) {
                //这里循环获取错误信息，可以自定义格式
                property = cv.getPropertyPath().toString();
                if (errorMap.get(property) != null) {
                    errorMap.get(property).append("," + cv.getMessage());
                } else {
                    StringBuilder sb = new StringBuilder();
                    sb.append(cv.getMessage());
                    errorMap.put(property, sb);
                }
            }
        }
        return errorMap.entrySet().stream().collect(Collectors.toMap(k -> k.getKey(), v -> v.getValue().toString()));
    }
}

测试GroupFirst.class:

    @Test
    public void test() {
        DataAuthContractParams params = new DataAuthContractParams();
        params.setBusinessName("f");
        params.setDataDemander("");
        params.setDataProvider("f");
        params.setPersonalDataName("");
        Re r = new Re();
        params.setR(r);



        Map<String, String> validMap = ValidatorUtils.validate(params, GroupFirst.class);
        System.out.println("error is: " + validMap);
    }

运行结果:
error is: {dataDemander=参数不能为null或空字符串, personalDataName=参数不能为null或空字符串}

测试GroupSecond.class:

    @Test
    public void test() {
        DataAuthContractParams params = new DataAuthContractParams();
        params.setBusinessName("f");
        params.setDataDemander("");
        params.setDataProvider("f");
        params.setPersonalDataName("");
        Re r = new Re();
        params.setR(r);



        Map<String, String> validMap = ValidatorUtils.validate(params, GroupSecond.class);
        System.out.println("error is: " + validMap);
    }

运行结果:
error is: {dataDemander=参数不能为null或空字符串, r.d=参数不能为null或空字符串}

测试GroupFirst.class+GroupSecond.class:

    @Test
    public void test() {
        DataAuthContractParams params = new DataAuthContractParams();
        params.setBusinessName("f");
        params.setDataDemander("");
        params.setDataProvider("f");
        params.setPersonalDataName("");
        Re r = new Re();
        params.setR(r);



        Map<String, String> validMap = ValidatorUtils.validate(params, GroupFirst.class, GroupSecond.class);
        System.out.println("error is: " + validMap);
    }

运行结果:
error is: {dataDemander=参数不能为null或空字符串, r.d=参数不能为null或空字符串, personalDataName=参数不能为null或空字符串}

spring mvc上使用分组校验：@org.springframework.validation.annotation.Validated({GroupFirst.class, GroupSecond.class})

相关链接资料
Spring4新特性——集成Bean Validation 1.1(JSR-349)到SpringMVC https://my.oschina.net/qjx1208/blog/200946
Java Bean Validation 最佳实践 http://www.cnblogs.com/beiyan/p/5946345.html