如何使用CrudRepository从数据库中获取'现在时间'？
问题描述：
我有实体的这个例子：如何使用CrudRepository从数据库中获取'现在时间'？
@Entity
public class User {
private String name;
private Date creationDate;
public User(String name) {
this.name = name;
this.creationDate= Calendar.getInstance().getTime();
}
}
和回购的这个例子：
public interface UserRepository extends JpaRepository<User, Long>, JpaSpecificationExecutor<User> {
public User findByName(String name);
}
但是，当我需要做的：
User user = new User();
我不能从再得到creationDate：
Calendar.getInstance().getTime();
因为有些人正在改变操作系统的时间，并且创建的时间被持续错误。所以我需要一些：
SELECT SYSDATE FROM DUAL;
SELECT now();
从用户设置creationDate。
我需要一个新的回购获得时间，或者我可以使用此UserRepository从数据库中获取creationDate？我试过创建一个UtilsRepository，在那里我可能会从数据库中得到日期：
public interface UtilsRepository extends JpaRepository<Date, String> {
@Modifying
@Transactional(readOnly = false)
@Query("select now()")
public Date getDataBaseDate();
}
但它不工作。我收到这个错误，我认为这不是最好的方法。发生
Exception in Application init method
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:389)
at com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:328)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at sun.launcher.LauncherHelper$FXHelper.main(Unknown Source)
Caused by: java.lang.RuntimeException: Exception in Application init method
at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:912)
at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$155(LauncherImpl.java:182)
at java.lang.Thread.run(Unknown Source)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'utilsRepository': Invocation of init method failed; nested exception is java.lang.IllegalArgumentException: Not a managed type: class java.util.Date
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1578)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:545)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:757)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:861)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:541)
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759)
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:369)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:313)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1185)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1174)
at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:841)
... 2 more
Caused by: java.lang.IllegalArgumentException: Not a managed type: class java.util.Date
at org.hibernate.jpa.internal.metamodel.MetamodelImpl.managedType(MetamodelImpl.java:210)
at org.springframework.data.jpa.repository.support.JpaMetamodelEntityInformation.<init>(JpaMetamodelEntityInformation.java:68)
at org.springframework.data.jpa.repository.support.JpaEntityInformationSupport.getEntityInformation(JpaEntityInformationSupport.java:67)
at org.springframework.data.jpa.repository.support.JpaRepositoryFactory.getEntityInformation(JpaRepositoryFactory.java:152)
at org.springframework.data.jpa.repository.support.JpaRepositoryFactory.getTargetRepository(JpaRepositoryFactory.java:99)
at org.springframework.data.jpa.repository.support.JpaRepositoryFactory.getTargetRepository(JpaRepositoryFactory.java:81)
at org.springframework.data.repository.core.support.RepositoryFactorySupport.getRepository(RepositoryFactorySupport.java:199)
at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.initAndReturn(RepositoryFactoryBeanSupport.java:266)
at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.afterPropertiesSet(RepositoryFactoryBeanSupport.java:252)
at org.springframework.data.jpa.repository.support.JpaRepositoryFactoryBean.afterPropertiesSet(JpaRepositoryFactoryBean.java:92)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1637)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1574)
... 18 more
答
我解决了这一点做用
@Query(value = "SELECT SYSDATE FROM DUAL", nativeQuery = true)
，在UserReposistory：
@Transactional(readOnly = false)
@Query("select CURRENT_TIMESTAMP from User")
public Date getCurrentTime();
答
Caused by: java.lang.IllegalArgumentException: Not a managed type: class java.util.Date因为日期是不是一个实体，所以你不能使用你的UtilsRepository原样。你应该能够在您的UserRepository
+0
我做了这样的事情，@Sean。稍后我会发布解决方案。谢谢。 – laccf
我会说，如果“有人”是允许的，并如果改变生产服务器的时间，你会遇到比创建日期错误更大的问题。从数据库获取当前tme不会有太大变化，因为这些人可能也会更改数据库服务器上的时间。 –
为什么该方法被标注为修改并且只读为false？ –
@JBNizet，在这种情况下，有必要这样做。 – laccf