第一次配置hibernate时，Junit测试时不报错的可能原因

前几天看了一下教程 ，自己试着配置了一下web下的hibernate，悲剧的时，出错了提示下面：
org.hibernate.HibernateException: Unable to get the default Bean Validation factory at org.hibernate.cfg.beanvalidation.BeanValidationActivator.applyDDL(BeanValidationActivator.java:127) at org.hibernate.cfg.Configuration.applyBeanValidationConstraintsO
在网上奔波了几天，都没打找到解决的办法，无奈啊，自己硬着头皮，看hibernate的帮助文档，搜索validation,打开有道词典边翻译边看帮助文档，希望它能帮我，功夫不负有心人，终于让我找到了一段：

23.1.1. Adding Bean Validation

To enable Hibernate’s Bean Validation integration, simply add a Bean Validation provider (preferably Hibernate Validation 4) on your classpath.

23.1.2. Configuration

By default, no configuration is necessary.

The Default group is validated on entity insert and update and the database model is updated accordingly based on the Default group as well.

You can customize the Bean Validation integration by setting the validation mode. Use the javax.persistence.validation.mode property and set it up for example in your persistence.xml file or your hibernate.cfg.xml file. Several options are possible:

auto (default): enable integration between Bean Validation and Hibernate (callback and ddl generation) only if Bean Validation is present in the classpath.
none: disable all integration between Bean Validation and Hibernate
callback: only validate entities when they are either inserted, updated or deleted. An exception is raised if no Bean Validation provider is present in the classpath.
ddl: only apply constraints to the database schema when generated by Hibernate. An exception is raised if no Bean Validation provider is present in the classpath. This value is not defined by the Java Persistence spec and is specific to Hibernate.
注意
You can use both callback and ddl together by setting the property to callback, dll

< persistence >
< persistence-unit >
< properties>
< property name=“javax.persistence.validation.mode”
value=“callback, ddl”/>
</ properties>
</ persistence-unit>
</ persistence>
This is equivalent to auto except that if no Bean Validation provider is present, an exception is raised.
If you want to validate different groups during insertion, update and deletion, use:

javax.persistence.validation.group.pre-persist: groups validated when an entity is about to be persisted (default to Default)
javax.persistence.validation.group.pre-update: groups validated when an entity is about to be updated (default to Default)
javax.persistence.validation.group.pre-remove: groups validated when an entity is about to be deleted (default to no group)
org.hibernate.validator.group.ddl: groups considered when applying constraints on the database schema (default to Default)
Each property accepts the fully qualified class names of the groups validated separated by a comma (,)
这里大意就是在hibernate.cfg.xml或者是persistence.xml文件下面需要配置javax.persistence.validation.mode属性

我不知道是什么意思，我于是直接改我的hibernate.cfg.xml文件里添加属性：

< property name=“javax.persistence.validation.mode”>none</ property>
可怜的我居然hibernate居然不报错了。兴奋啊,javax.persistence.validation.mode默认情况下是auto的，就是说如果不设置的话它是会自动去你的classpath下面找一个bean-validation**包，但是找不到，所以beanvalitionFactory错误。

哎，今天终于可以轻松下了&……

作者：Blessing_H
来源：优快云
原文：https://blog.youkuaiyun.com/huangbiao86/article/details/6594350
版权声明：本文为博主原创文章，转载请附上博文链接！