Java Hibernate:object.org.Hibernate.MappingException

这是我面临的一个例外……每当我试图将对象保存到数据库中时，就会发生这种情况。。i、 e在session.save上

Failed to create sessionFactory object.org.hibernate.MappingException: Unknown entity: com.java.learn.pojo.Employee
Apr 22, 2017 3:16:01 AM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl stop
INFO: HHH10001008: Cleaning up connection pool [jdbc:mysql://localhost/test]
Apr 22, 2017 3:16:01 AM org.hibernate.engine.jdbc.connections.internal.PooledConnections close
ERROR: Collection leak detected: there are 1 unclosed connections upon shutting down pool jdbc:mysql://localhost/test
Apr 22, 2017 3:16:34 AM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [Learn] in context with path [/Practice] threw exception [Handler processing failed; nested exception is java.lang.ExceptionInInitializerError] with root cause
org.hibernate.MappingException: Unknown entity: com.java.learn.pojo.Employee
    at org.hibernate.metamodel.internal.MetamodelImpl.entityPersister(MetamodelImpl.java:620)
    at org.hibernate.internal.SessionImpl.getEntityPersister(SessionImpl.java:1634)
    at org.hibernate.event.internal.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:104)
    at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:192)
    at org.hibernate.event.internal.DefaultSaveEventListener.saveWithGeneratedOrRequestedId(DefaultSaveEventListener.java:38)
    at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:177)
    at org.hibernate.event.internal.DefaultSaveEventListener.performSaveOrUpdate(DefaultSaveEventListener.java:32)
    at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:73)
    at org.hibernate.internal.SessionImpl.fireSave(SessionImpl.java:689)
    at org.hibernate.internal.SessionImpl.save(SessionImpl.java:681)
    at org.hibernate.internal.SessionImpl.save(SessionImpl.java:676)
    at com.java.learn.dao.DaoClass.callDatabase(DaoClass.java:29)
    at com.java.learn.service.ServiceClass.callDao(ServiceClass.java:17)
    at com.java.learn.controller.ControllerClass.personController(ControllerClass.java:26)
    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:497)
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221)
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:776)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:705)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:966)
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:857)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:842)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:522)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1095)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:672)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1500)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Thread.java:745)

这是我用来保存对象的java代码

try
        {
            Configuration configuration = new Configuration().configure();
            StandardServiceRegistryBuilder builder =
                new StandardServiceRegistryBuilder().applySettings(configuration.getProperties());
            factory = configuration.buildSessionFactory(builder.build());
            Session session = factory.openSession();
            Transaction t = session.beginTransaction();
            Employee e = new Employee(1, "", "", 3);
            e.setFirstName("sparsh");
            session.save(e);
            t.commit();
            System.out.println("in dao");
        }
        catch (Throwable ex)
        {
            System.err.println("Failed to create sessionFactory object." + ex);
            factory.close();
            throw new ExceptionInInitializerError(ex);
        }

这是我在项目中包含的jar文件

这是cfg文件

<hibernate-configuration>
    <session-factory>
        <property name="hibernate.dialect">
            org.hibernate.dialect.MySQLDialect
        </property>
        <property name="hibernate.connection.driver_class">
            com.mysql.jdbc.Driver
        </property>

        <!-- Assume students is the database name -->
        <property name="hibernate.connection.url">
            jdbc:mysql://localhost/test
        </property>
        <property name="hibernate.connection.username">
            root
        </property>
        <property name="hibernate.connection.password">
            root1
        </property>
        <property name="hbm2ddl.auto">create</property>
        <property name="show_sql">true</property>
        <mapping class="com.java.learn.pojo.Employee"/>
    </session-factory>
</hibernate-configuration>

---

请帮助

这是Hibernate 5的问题-您不能使用Hibernate 4方法进行配置。此代码不正确：

Configuration configuration = new Configuration().configure();
StandardServiceRegistryBuilder builder = new StandardServiceRegistryBuilder().applySettings(configuration.getProperties());
factory = configuration.buildSessionFactory(builder.build());

请检查这个

---

show us Employee POJO？added Employee.java如果我们不给它，它将把它作为类的名称。。。对吗？@Yogidlip不认为表名应该有任何区别，因为hibernate应该能够使用其命名策略推断名称，因为name=“EMPLOYEE”是可选的。属性

name=“EMPLOYEE”

在“表映射”中是可选的。进行了更改。。。现在面临的问题是：com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException:您的SQL语法有错误；在第行的“type=MyISAM”附近，查看与您的MySQL服务器版本对应的手册，了解要使用的正确语法1@sparsh610如果您使用的是

@GeneratedValue

@v.ladynev，则不应设置

id

，我最近从4迁移到Hibernate 5，但没有此类问题。感谢您的精彩lib@Sneh，欢迎您：）。谢谢你玩图书馆。可能您使用了其他配置方法。我删除了id，但仍然面临相同的问题，同样在打印hibernate查询时，我发现创建表EMPLOYEE（id integer非null自动增量，first name varchar（255），last name varchar（255），salary integer，primary key（id））type=MyISAM。。。。输入isam。。不知道从哪里来的

Configuration configuration = new Configuration().configure();
StandardServiceRegistryBuilder builder = new StandardServiceRegistryBuilder().applySettings(configuration.getProperties());
factory = configuration.buildSessionFactory(builder.build());