Java JPA - 未知实体 bean 类
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JPA - Unknown entity bean class
提问by arinte
Hopefully, I can explain this issue properly. I have 3 classes that deals with my entities.
希望我能正确解释这个问题。我有 3 个处理我的实体的类。
@MappedSuperclass
public abstract class Swab implements ISwab {
...
private Collection<SwabAccounts> accounts;
...
}
@Entity
@Table(name="switches")
@DiscriminatorColumn(name="type")
@DiscriminatorValue(value="DMS500")
public class DmsSwab extends Swab implements ISwab, Serializable {
...
private ObjectPool pool;
...
@Transient
public ObjectPool getPool(){
return pool;
}
...
}
@Entity(name="swab_accounts")
public class SwabAccounts implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private int swab_account_id;
private int swab_id;
...
}
And in a EJB a query is being doing this way
并且在 EJB 中，查询正在以这种方式进行
DmsSwab dms = em.find(DmsSwab.class, 2);
List<Swab> s = new ArrayList<Swab>(1);
s.add(dms);
My persistence.xml looks like this:
我的persistence.xml 看起来像这样：
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="1.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd">
<persistence-unit name="dflow-pu" transaction-type="RESOURCE_LOCAL">
<provider>oracle.toplink.essentials.PersistenceProvider</provider>
<class>com.dcom.sap.dms.DmsSwab</class>
<class>com.dcom.sap.jpa.SwabAccounts</class>
<properties>
<property name="toplink.jdbc.user" value="dflow"/>
<property name="toplink.jdbc.password" value="dflow"/>
<property name="toplink.jdbc.url" value="jdbc:mysql://itcd-400447:3306/dflow"/>
<property name="toplink.jdbc.driver" value="com.mysql.jdbc.Driver"/>
</properties>
</persistence-unit>
</persistence>
I get this error:
我收到此错误：
java.lang.IllegalArgumentException: Unknown entity bean class: class com.dcom.sap.dms.DmsSwab, please verify that this class has been marked with the @Entity annotation.
com.dcom.sap.SwabException: java.lang.IllegalArgumentException: Unknown entity bean class: class com.dcom.sap.dms.DmsSwab, please verify that this class has been marked with the @Entity annotation.
Caused by: java.lang.IllegalArgumentException: Unknown entity bean class: class com.dcom.sap.dms.DmsSwab, please verify that this class has been marked with the @Entity annotation.
at oracle.toplink.essentials.internal.ejb.cmp3.base.EntityManagerImpl.findInternal(EntityManagerImpl.java:306)
at oracle.toplink.essentials.internal.ejb.cmp3.EntityManagerImpl.find(EntityManagerImpl.java:148)
I am running netbeans 6.1 with the version of glassfish that comes with it. MySql 5.0.
我正在运行 netbeans 6.1 及其附带的 glassfish 版本。mysql 5.0。
回答by Nicolas
According to the error message and what I figure from your code, the error seems to be in the persistence.xml file, can you be a bit more verbose ?
根据错误消息和我从您的代码中得出的结论，错误似乎在persistence.xml 文件中，您能说得更详细一点吗？
回答by Andy
define this entity in class tag inside the persistence.xml
在persistence.xml中的class标签中定义这个实体
回答by clebertx
I had the same error and, complementing the information above, my case was a ClassLoader issue. My app has three files. A ejb-module.jar which depends on app-lib.jar (library that contains pojo and database entities) and a web-module.war which depends on app-lib.jar.
我有同样的错误，补充上面的信息，我的情况是一个类加载器问题。我的应用程序有三个文件。一个 ejb-module.jar 依赖于 app-lib.jar（包含 pojo 和数据库实体的库）和一个 web-module.war 依赖于 app-lib.jar。
In the deployment, the app-lib.jar was loaded twice by the glassfish. Googling, I found out that I should copy the app-lib.jar to a "shared" lib in the glassfish domain. I've copied the postgresql.jar to "domain-dir/lib" and my app-lib.jar to "domain-dir/lib/applibs". Have it done, the app worked like a charm.
在部署中，app-lib.jar 被 glassfish 加载了两次。谷歌搜索，我发现我应该将 app-lib.jar 复制到 glassfish 域中的“共享”库。我已将 postgresql.jar 复制到“domain-dir/lib”并将我的 app-lib.jar 复制到“domain-dir/lib/applibs”。完成后，该应用程序就像一个魅力。
The used explanation can be found here: http://docs.oracle.com/cd/E19798-01/821-1752/beade/index.html
使用的解释可以在这里找到：http: //docs.oracle.com/cd/E19798-01/821-1752/beade/index.html
回答by Mario Barreto MX
I solved this issue creating a ContextListener in to my Web App, invoking the close of the entity manager factory at destroy context, :
我解决了这个问题，在我的 Web 应用程序中创建了一个 ContextListener，在销毁上下文时调用实体管理器工厂的关闭，：
public void contextDestroyed(ServletContextEvent servletContextEvent) {
try {
logger.info("contextDestroyed...");
LifeCycleManager lifeCycleManager = ServiceLocator.getLifeCycleManager();
lifeCycleManager.closeEntityManagerFactory();
} catch (Exception e) {
logger.error(e.getMessage(), e);
}
}
I also create a bean with name LifeCycleManager and inside them invoke a DAO method to close the entity manager factory:
我还创建了一个名为 LifeCycleManager 的 bean，并在其中调用 DAO 方法来关闭实体管理器工厂：
public void closeEntityManagerFactory() throws BusinessException {
logger.info("closeEntityManager");
try {
logger.info("closing entity manager factory...");
genericDAO.closeEntityManagerFactory();
logger.info("Entity manager factiry closed");
} catch (Exception e) {
throw new BusinessException(BusinessErrorCode.CODIGO_EJEMPLO_01, Severity.ERROR);
}
}
Inside the DAO:
DAO 内部：
...
...
@Autowired
private EntityManagerFactory entityManagerFactory;
...
...
public void closeEntityManagerFactory() {
logger.info("closing entity manager factory");
getEntityManagerFactory().close();
logger.info("entity manager factory closed");
}
Using this each time I deploy a change from my eclipse environment the destroy context is invoked. I hope could help you guys, my environment is WebLogic Server 11gR1 and JPA 1.0.
每次我从我的 Eclipse 环境部署更改时使用它，调用 destroy 上下文。我希望可以帮助你们，我的环境是 WebLogic Server 11gR1 和 JPA 1.0。
