为什么我的实体不能在SpringBoot中使用，尽管它在没有 [英] Why does my Entity does not work with SpringBoot although it works without
问题描述
((请注意:正在调查此问题我更好地发现了我在这里介绍的问题的根源)
(Please note : while investigating on this issue I better spotted the source of problem that I introduce here)
我对Hibernate和SpringBoot还是陌生的.我的项目涉及一个搜索引擎，该引擎的索引部分(javafx客户端)和搜索部分(web客户端)是分开的. Web客户端使用SpringBoot，在用户请求过程中，我需要检索Solr索引上的信息以进行搜索.这些信息存储在Hibernate/H2本地数据库中，在这里我使用以下Entity类:
I am very new to Hibernate and SpringBoot. My project deals with a search engine which indexing (javafx client) and searching (web client) parts are separated. The web client uses SpringBoot and during the process of the user's request, I need to retrieve information on the Solr Index to search against. These information are stored in a Hibernate / H2 local database where I use the following Entity class :
@Entity
@Table(name = "IndexSetups")
@Access(AccessType.PROPERTY)
public class IndexSetup {
private final SimpleIntegerProperty id = new SimpleIntegerProperty();
@Id
@GeneratedValue(strategy = GenerationType.AUTO) // For H2 AUTO is required to auto increment the id
public int getId() {
return id.get();
}
//... other properties, getters and setters
}
LocalDatabase类具有一种方法，该方法可以列出数据库中的所有IndexSetup(还有其他方法，但是专注于此方法足以理解该问题).我需要在控制器中调用它，但得到一个不是实体:类IndexSetup" .
A LocalDatabase class features a method to list all IndexSetups from the DB (there are also other methods but focusing on this one is enough to understand the issue). I need to call it in a controller but I get a "Not an entity : class IndexSetup".
但是，使用我的实体的唯一方法是阻止SpringBoot的启动(即，注释以SpingApplication.run(...)开头的行):
However the only way to use my Entity is to prevent the launching of SpringBoot (ie commenting the line starting with SpingApplication.run(...)) :
@SpringBootApplication
public class ServerApplication {
public static void main(String[] args) {
// SpringApplication.run(ServerApplication.class, args);
ArrayList<IndexSetup> availableSearchIndex =
LocalDatabase.getInstance(false) // no GUI
.getAllIndexSetups();
// The list is displayed as long as SpringApplication.run() call is commented. Otherwise "Not an entity"
System.err.println("The Index setups are " + availableSearchIndex);
}
}
当然这不是解决方案，因为我确实需要通过Spring Boot :-D处理用户的请求！
Of course this is not a solution since I do need to process the user's request via Spring Boot :-D!
最后，hibernate.cfg.xml文件读取:
Finally the hibernate.cfg.xml file reads :
<hibernate-configuration>
<session-factory>
<!-- Database connection settings -->
<property name="connection.driver_class">org.h2.Driver</property>
<!--The db file resides wihtin the parent project (so one level above the calling project see ../)-->
<!--We use the auto server mode to be able to open the database from server and from indexer simultaneously
see http://www.h2database.com/html/features.html#auto_mixed_mode -->
<property name="connection.url">jdbc:h2:file:../MyAppDB;DB_CLOSE_ON_EXIT=TRUE;AUTO_SERVER=TRUE</property>
<property name="connection.username">test</property>
<property name="connection.password"/>
<!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size">1</property>
<!-- SQL dialect -->
<property name="dialect">org.hibernate.dialect.H2Dialect</property>
<!-- Disable the second-level cache -->
<property name="cache.provider_class">org.hibernate.cache.internal.NoCacheProvider</property>
<!-- Echo all executed SQL to stdout -->
<property name="show_sql">false</property>
<!-- Updates the existing database schema on startup -->
<property name="hbm2ddl.auto">update</property>
<!-- The mapping information of entities -->
<mapping class="my.package.Entities.IndexSetup"/>
</session-factory>
</hibernate-configuration>
堆栈跟踪为:
Exception in thread "restartedMain" java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49)
Caused by: java.lang.IllegalArgumentException: Not an entity: class my.package.Entities.IndexSetup
at org.hibernate.metamodel.internal.MetamodelImpl.entity(MetamodelImpl.java:457)
at org.hibernate.query.criteria.internal.QueryStructure.from(QueryStructure.java:126)
at org.hibernate.query.criteria.internal.CriteriaQueryImpl.from(CriteriaQueryImpl.java:153)
at my.package.LocalDatabase.getAllIndexSetups(LocalDatabase.java:99)
at my.package.ServerApplication.main(ServerApplication.java:15)
我刚刚注意到Spring Boot在启动时打印的这两行:
And I've just noticed those two lines printed by Spring Boot at startup :
2018-10-15 11:47:46.208 INFO 27730 --- [ restartedMain] org.hibernate.cfg.Environment : HHH000206: hibernate.properties not found // Maybe this one is not just "INFO"
2018-10-15 11:47:46.591 WARN 27730 --- [ restartedMain] org.hibernate.orm.connections.pooling : HHH10001002: Using Hibernate built-in connection pool (not for production use!)
2018-10-15 11:47:46.594 INFO 27730 --- [ restartedMain] org.hibernate.orm.connections.pooling : HHH10001005: using driver [org.h2.Driver] at URL [jdbc:h2:file:../MyAppDB;DB_CLOSE_ON_EXIT=TRUE;FILE_LOCK=NO] // Just to show that my bibernate.cfg.xml is found
它似乎不太可能是依赖性问题，因为它仅在运行Spring应用程序时停止工作.
It looks unlikely to be a dependency problem as it only stops working when Spring application is run.
所以我的问题是:如何使Entity在SpringBoot中工作?
So my question is : what should I do to make my Entity work within SpringBoot ?
任何帮助，不胜感激！
推荐答案
将@EntityScan添加到ServerApplication.class.
Add @EntityScan to ServerApplication.class.
@EntityScan(org.springframework.boot.autoconfigure.domain.EntityScan)标识特定持久性上下文应使用哪些类.
@EntityScan (org.springframework.boot.autoconfigure.domain.EntityScan) identifies which classes should be used by a specific persistence context.
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