Spring Data @CreatedDate注释对我不起作用

本文介绍了Spring Data @CreatedDate注释对我不起作用的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我正在研究使用Spring Data的项目。我想使用 @CreatedDate 注释填写 creationTime 字段，而不是使用 @PreUpdate 或 @PrePersist 注释（以这种方式完美地运行）。当我使用 @CreatedDate 执行此操作时，它只会将此字段留空。我使用postgresql数据库。 文档不是很有帮助。

I am working on project where I use Spring Data. I wanted to fill in creationTime field using @CreatedDate annotation instead using method with @PreUpdate or @PrePersist annotation (doing it this way it works perfectly). When I do it with @CreatedDate it just leaves this field blank. I use postgresql database. Documentation is not very helpful.

您有什么想法我该如何解决？谢谢！

Do you have any idea how can I fix it? Thank you!

import org.springframework.data.annotation.CreatedDate; @Entity @Table(name = "software") public class Software implements Serializable { // ... @Column(name = "creation_time") @CreatedDate private Date creationTime; //... }

我的 applicationContext ：

<jpa:repositories base-package="path.to.dao"/> <context:component-scan base-package="path.to.dao"/> <context:property-placeholder location="classpath:application.properties"/> <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="driverClassName" value="${db.driver}"/> <property name="url" value="${db.url}"/> <property name="username" value="${db.username}"/> <property name="password" value="${db.password}"/> </bean> <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean"> <property name="packagesToScan" value="path.to.bean"/> <property name="dataSource" ref="dataSource"/> <property name="jpaVendorAdapter" ref="jpaAdapter"/> <property name="jpaProperties"> <props> <prop key="hibernate.dialect">${hibernate.dialect}</prop> <prop key="hibernate.show_sql">${hibernate.show_sql}</prop> <prop key="hibernate.format_sql">${hibernate.format_sql}</prop> <prop key="hibernate.ejb.naming_strategy">${hibernate.ejb.naming_strategy}</prop> <prop key="hibernate.hbm2ddl.auto">${hibernate.hbm2ddl.auto}</prop> </props> </property> </bean> <bean id="jpaAdapter" class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"/> <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager"> <property name="entityManagerFactory" ref="entityManagerFactory"/> </bean>

推荐答案

我可能一直处于类似的情况，我希望Spring Data JPA @CreatedDate 注释可以工作，但是不需要进行用户级审计否则在他们的文档中描述。

I may have been in a similar situation where I wanted the Spring Data JPA @CreatedDate annotation to work, but had no need for the user-level auditing that is otherwise described in their documentation.

为了让基于注释的审计工作，我不得不在我的项目中添加一个实现 org的类.springframework.data.domain.AuditorAware 。这很奇怪，因为您实际上似乎并没有使用您将要实现的 getCurrentAuditor（）方法返回的值;我只返回 null 。

To get the annotation-based auditing to work, I had to nonetheless add a class to my project that implemented org.springframework.data.domain.AuditorAware. This is odd because you don't actually seem to use the value returned from the getCurrentAuditor() method that you'll be implementing; mine just returns null.

public class NullAuditorBean implements AuditorAware { @Override public Object getCurrentAuditor() { return null; } }

然后我需要引用我的空对象 AuditorAware 在我的 applicationContext 的条目中实现，以激活JPA审核。我必须确保在指定 jpa：repositories 的行之前执行此操作。这看起来像：

I then needed to reference my "null object" AuditorAware implementation in an entry in my applicationContext to activate the JPA auditing. I had to make sure I did this before the line that specifies the jpa:repositories. This looks something like:

<bean id="auditorBean" class="your.package.subbed.here.NullAuditorBean"/> <jpa:auditing auditor-aware-ref="auditorBean"/>

我还必须添加 orm.xml file，并且需要正式引用它作为我的 entityManagerFactory bean的属性，如下所示：

I also had to add an orm.xml file, and needed to formally reference it as a property of my entityManagerFactory bean, like so:

<property name="mappingResources"> <value>META-INF/orm.xml</value> </property>

确保 META-INF / orm.xml 条目与您的编译输出一起存储（我的WAR在我的WAR下 WEB-INF / classes 。

Make sure this META-INF/orm.xml entry is stored with your compile output (mine is in my WAR under WEB-INF/classes.

记录中的 orm.xml 文件包含一些样板文件，可以在这个相关的问题。

That orm.xml file, for the record, contained some boilerplate, which can be found in the answer to this related question.

这是我开始工作时需要做相当多的工作。您可能更喜欢以前的工作解决方案！

It was a fair amount of work when I got this working. You may prefer your previous working solution!