我正在使用JPA创建EJB应用程序。我创建了使用 @PersistenceContext 和实体管理器的EJBBean。我还在 Persistence.xml 文件中提供了具有 Hibernate 信息的设置。我正在尝试使用 transaction-type = JTA 并尝试使用JNDI 访问 DataSource。我还在 Websphere Liberty 的 server.xml 文件中提供了一些信息
但是,我收到一条错误消息 -
javax.ejb.EJBException:CWNEN0030E:服务器无法获取java:comp / env / SolarUniversityJpa引用的对象实例。异常消息是:java.lang.RuntimeException:CWWJP0050E:无法找到持久性提供程序org.hibernate.ejb.HibernatePersistence。嵌套异常是:java.lang.RuntimeException:java.lang.RuntimeException:CWWJP0050E:无法找到持久性提供程序org.hibernate.ejb.HibernatePersistence。
有关详细信息,请参阅Server.xml文件后面提到的错误消息
的Servlet
@WebServlet("/StudentServlet")
public class StudentServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
@EJB
StudentEjbBean studentEjbBean;
public StudentServlet() {
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
studentEjbBean.testJpa();
}
}
EjbBean
@Stateless
@LocalBean
public class StudentEjbBean {
@PersistenceContext(name="SolarUniversityJpa")
EntityManager entityManager;
public StudentEjbBean() {
}
public void testJpa()
{
StudentDao studentDao = new StudentDaoImpl();
studentDao.SaveInformation(entityManager);
}
}
的persistence.xml
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.1"
xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
<persistence-unit name="SolarUniversityJpa"
transaction-type="JTA">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<jta-data-source>java:global/env/jdbc/MySql</jta-data-source>
<class>com.student.entity.StudentEntity</class>
<properties>
<property name="connection.driver_class" value="com.mysql.jdbc.Driver" />
<property name="hibernate.connection.url" value="jdbc:mysql://localhost:3306/SolarUniversity" />
<property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect" />
<property name="hibernate.hbm2ddl.auto" value="create" />
<property name="hibernate.show_sql" value="true" />
<property name="hibernate.format_sql" value="true" />
</properties>
</persistence-unit>
</persistence>
的Server.xml
<server description="new server">
<!-- Enable features -->
<featureManager>
<feature>webProfile-7.0</feature>
<feature>localConnector-1.0</feature>
</featureManager>
<!-- To access this server from a remote client add a host attribute to
the following element, e.g. host="*" -->
<httpEndpoint httpPort="9080" httpsPort="9443"
id="defaultHttpEndpoint" />
<!-- Automatically expand WAR files and EAR files -->
<applicationManager autoExpand="true" />
<applicationMonitor updateTrigger="mbean" />
<jdbcDriver id="mySqlEmbedded" libraryRef="mySqlLib" />
<library id="mySqlLib" filesetRef="mySqlFileSet" />
<fileset id="mySqlFileSet" dir="E:/Backups"
includes="mysql-connector-java-5.1.34.jar" />
<dataSource id="jdbc/samplejpadatasource" jndiName="jdbc/MySql"
jdbcDriverRef="mySqlEmbedded">
<properties user="root" password="root"
URL="jdbc:mysql://localhost:3306/SolarUniversity">
</properties>
</dataSource>
<enterpriseApplication id="SolarUniversityEAR"
location="SolarUniversityEAR.ear" name="SolarUniversityEAR">
<!-- <classloader commonLibraryRef="MySQLLib" /> -->
</enterpriseApplication>
</server>
例外情况
[ERROR ] CNTR0019E: EJB threw an unexpected (non-declared) exception during invocation of method "testMessage". Exception data: javax.ejb.EJBException: CWNEN0030E: The server was unable to obtain an object instance for the java:comp/env/SolarUniversityJpa reference. The exception message was: java.lang.RuntimeException: CWWJP0050E: Unable to locate persistence provider org.hibernate.ejb.HibernatePersistence.; nested exception is: java.lang.RuntimeException: java.lang.RuntimeException: CWWJP0050E: Unable to locate persistence provider org.hibernate.ejb.HibernatePersistence.
at com.ibm.ejs.container.util.ExceptionUtil.EJBException(ExceptionUtil.java:461)
at [internal classes]
at com.ejb.stateless.student.EJSLocalNSLStudentEjbBean_58c656c8.testMessage(EJSLocalNSLStudentEjbBean_58c656c8.java)
at com.servlet.student.StudentServlet.doPost(StudentServlet.java:56)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1290)
at [internal classes]
Caused by (repeated) ... : java.lang.RuntimeException: java.lang.RuntimeException: CWWJP0050E: Unable to locate persistence provider org.hibernate.ejb.HibernatePersistence.
at com.ibm.ws.jpa.management.JPAPUnitInfo.getEntityManagerFactory(JPAPUnitInfo.java:960)
... 7 more
Caused by: java.lang.ClassNotFoundException: org.hibernate.ejb.HibernatePersistence
at com.ibm.ws.classloading.internal.AppClassLoader.findClassCommonLibraryClassLoaders(AppClassLoader.java:499)
... 1 more
[ERROR ] SRVE0777E: Exception thrown by application class 'com.ibm.ejs.container.util.ExceptionUtil.EJBException:461'
javax.ejb.EJBException: CWNEN0030E: The server was unable to obtain an object instance for the java:comp/env/SolarUniversityJpa reference. The exception message was: java.lang.RuntimeException: CWWJP0050E: Unable to locate persistence provider org.hibernate.ejb.HibernatePersistence.; nested exception is: java.lang.RuntimeException: java.lang.RuntimeException: CWWJP0050E: Unable to locate persistence provider org.hibernate.ejb.HibernatePersistence.
at com.ibm.ejs.container.util.ExceptionUtil.EJBException(ExceptionUtil.java:461)
at [internal classes]
at com.ejb.stateless.student.EJSLocalNSLStudentEjbBean_58c656c8.testMessage(EJSLocalNSLStudentEjbBean_58c656c8.java)
at com.servlet.student.StudentServlet.doPost(StudentServlet.java:56)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1290)
at [internal classes]
Caused by (repeated) ... : java.lang.RuntimeException: java.lang.RuntimeException: CWWJP0050E: Unable to locate persistence provider org.hibernate.ejb.HibernatePersistence.
at com.ibm.ws.jpa.management.JPAPUnitInfo.getEntityManagerFactory(JPAPUnitInfo.java:960)
... 7 more
Caused by: java.lang.ClassNotFoundException: org.hibernate.ejb.HibernatePersistence
at com.ibm.ws.classloading.internal.AppClassLoader.findClassCommonLibraryClassLoaders(AppClassLoader.java:499)
... 1 more
[ERROR ] SRVE0315E: An exception occurred: java.lang.Throwable: javax.ejb.EJBException: CWNEN0030E: The server was unable to obtain an object instance for the java:comp/env/SolarUniversityJpa reference. The exception message was: java.lang.RuntimeException: CWWJP0050E: Unable to locate persistence provider org.hibernate.ejb.HibernatePersistence.; nested exception is: java.lang.RuntimeException: java.lang.RuntimeException: CWWJP0050E: Unable to locate persistence provider org.hibernate.ejb.HibernatePersistence.
at com.ibm.ws.webcontainer.webapp.WebApp.handleRequest(WebApp.java:5000)
at [internal classes]
Caused by: javax.ejb.EJBException: CWNEN0030E: The server was unable to obtain an object instance for the java:comp/env/SolarUniversityJpa reference. The exception message was: java.lang.RuntimeException: CWWJP0050E: Unable to locate persistence provider org.hibernate.ejb.HibernatePersistence.; nested exception is: java.lang.RuntimeException: java.lang.RuntimeException: CWWJP0050E: Unable to locate persistence provider org.hibernate.ejb.HibernatePersistence.
at com.ibm.ejs.container.util.ExceptionUtil.EJBException(ExceptionUtil.java:461)
at [internal classes]
at com.ejb.stateless.student.EJSLocalNSLStudentEjbBean_58c656c8.testMessage(EJSLocalNSLStudentEjbBean_58c656c8.java)
at com.servlet.student.StudentServlet.doPost(StudentServlet.java:56)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1290)
... 1 more
Caused by (repeated) ... : java.lang.RuntimeException: java.lang.RuntimeException: CWWJP0050E: Unable to locate persistence provider org.hibernate.ejb.HibernatePersistence.
at com.ibm.ws.jpa.management.JPAPUnitInfo.getEntityManagerFactory(JPAPUnitInfo.java:960)
... 7 more
Caused by: java.lang.ClassNotFoundException: org.hibernate.ejb.HibernatePersistence
at com.ibm.ws.classloading.internal.AppClassLoader.findClassCommonLibraryClassLoaders(AppClassLoader.java:499)
... 1 more
答案 0 :(得分:1)
异常消息表明无法找到Hibernate类。这是预期的,因为Liberty不在jpa-2.0
(OpenJPA)或jpa-2.1
(eclipselink)功能中提供Hibernate类。
如果你想在Liberty上使用Hibernate,你需要自己下载Hibernate jar并将它们包含在你的应用程序中或配置一个共享库。
假设您已经在C:/hibernate
位置使用了Hibernate jar,您可以将以下内容添加到server.xml:
<library id="HibernateLib">
<fileset dir="C:/hibernate" includes="*.jar"/>
</library>
然后为您的应用程序提供共享库,如下所示:
<enterpriseApplication id="SolarUniversityEAR" location="SolarUniversityEAR.ear" name="SolarUniversityEAR">
<classloader commonLibraryRef="HibernateLib"/>
</enterpriseApplication>
此外,这是一个有用的示例,可以解决: Liberty JPA Hibernate Sample
答案 1 :(得分:0)
感谢 Andy Guibert 提出建议。它可能对其他人有帮助。以下是我解决问题的方法。
问题1:
我采用了Andy所说的相同方法。
问题2:
[错误] CNTR0020E:EJB抛出了意外(未声明)异常 在bean上调用方法“testMessage”期间 “将beanId(SolarUniversityEAR#SolarUniversityEjb.jar#StudentEjb豆, null)“。异常数据:java.lang.AbstractMethodError: org.hibernate.ejb.EntityManagerFactoryImpl.createEntityManag ER(Ljavax / persistenc E / SynchronizationTypë; Ljava / util的/地图;)LJ avax /持久/ ENT ityManager; 强> 的&GT;在 com.ibm.ws.jpa.container.v21.internal.JPA21Runtime.createEnt ityManagerInstance(j PA21Runtime.java:104)强>
我下载了支持Jpa 2.1的新版Hibernate。在此之后,我又遇到了另一个问题
问题3:
CNTR0020E: EJB期间抛出了意外(未声明)的异常 在bean上调用方法“testMessage” “将beanId(SolarUniversityEAR#SolarUniversityEjb.jar#StudentEjbBean, null)“。异常数据:java.lang.NullPointerException
为了解决这个问题,我在Persistence.xml中添加了以下代码(因为我使用的是 transaction-type =“JTA”)。这特定于WebSphere Liberty。资料来源:7.5.9. org.hibernate.service.jta.platform.spi.JtaPlatform
<property name="hibernate.transaction.jta.platform"
value="org.hibernate.service.jta.platform.internal.WebSphereExtendedJtaPlatform" />
最后,我能够在数据库中保存信息。