在尝试运行 AppEngine stadard Java 代码(3 个月前成功运行(时，使用mvn appengine:run然后出现错误。所以尝试了我另一个堆栈溢出案例中提到的步骤。将所有依赖项更改为最新版本后(很少有重大更改，如 hibernate 3 到 hibernate 6 版本(，然后得到 java.lang.NoClassDefFoundError：org/hibernate/jpa/HibernateEntityManagerFactory。
问题我注意到"hibernate-entitymanager"在"hibernate-core"atrifact中不可用，所以我得到了像类"org/hibernate/jpa/HibernateEntityManagerFactory"这样的错误。根据 mvn 存储库信息，此"休眠实体管理器"工件已在最新版本中移至"休眠核心"视室。但是当我在 POM 文件中使用 org.hibernate.orm -> 休眠核心依赖项时，然后出现错误，我也无法在该工件中找到 hibernate-entitymanager 依赖项。所以想知道获取休眠实体管理器类的替代依赖项是什么，或者从哪里获取它。
以下是突出显示的详细错误日志，
[INFO] GCLOUD: Sep 24, 2019 9:47:52 AM com.google.appengine.tools.development.ApiProxyLocalImpl log
[INFO] GCLOUD: INFO: javax.servlet.ServletContext log: No Spring WebApplicationInitializer types detected on classpath
[INFO] GCLOUD: Sep 24, 2019 9:47:52 AM com.google.appengine.tools.development.ApiProxyLocalImpl log
[INFO] GCLOUD: INFO: javax.servlet.ServletContext log: Initializing Spring root WebApplicationContext
[INFO] GCLOUD: 2019-09-24 15:17:56.171:WARN:oejw.WebAppContext:main: Failed startup of context c.g.a.t.d.j.DevAppEngineWebAppContext@c3177d5{/,file:///C:/Lourdu/Development/RBR/target/rbr-1/,UNAVAILABLE}{C:LourduDevelopmentRBRtargetrbr-1}
[INFO] GCLOUD: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in ServletContext resource [/WEB-INF/jpaContext.xml]: Cannot create inner bean 'org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter#ddf20fd' of type [org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter] while setting bean property 'jpaVendorAdapter'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter#ddf20fd' defined in ServletContext resource [/WEB-INF/jpaContext.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter]: Constructor threw exception; nested exception is java.lang.NoClassDefFoundError: org/hibernate/jpa/HibernateEntityManagerFactory
[INFO] GCLOUD: at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:361)
[INFO] GCLOUD: at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:124)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1681)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1433)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:592)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320)
[INFO] GCLOUD: at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
[INFO] GCLOUD: at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1105)
[INFO] GCLOUD: at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:867)
[INFO] GCLOUD: at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:549)
[INFO] GCLOUD: at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:400)
[INFO] GCLOUD: at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:291)
[INFO] GCLOUD: at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:103)
[INFO] GCLOUD: at org.eclipse.jetty.server.handler.ContextHandler.callContextInitialized(ContextHandler.java:957)
[INFO] GCLOUD: at org.eclipse.jetty.servlet.ServletContextHandler.callContextInitialized(ServletContextHandler.java:553)
[INFO] GCLOUD: at org.eclipse.jetty.server.handler.ContextHandler.startContext(ContextHandler.java:922)
[INFO] GCLOUD: at org.eclipse.jetty.servlet.ServletContextHandler.startContext(ServletContextHandler.java:365)
[INFO] GCLOUD: at org.eclipse.jetty.webapp.WebAppContext.startWebapp(WebAppContext.java:1497)
[INFO] GCLOUD: at org.eclipse.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1459)
[INFO] GCLOUD: at org.eclipse.jetty.server.handler.ContextHandler.doStart(ContextHandler.java:852)
[INFO] GCLOUD: at org.eclipse.jetty.servlet.ServletContextHandler.doStart(ServletContextHandler.java:278)
[INFO] GCLOUD: at org.eclipse.jetty.webapp.WebAppContext.doStart(WebAppContext.java:545)
[INFO] GCLOUD: at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
[INFO] GCLOUD: at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:167)
[INFO] GCLOUD: at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:110)
[INFO] GCLOUD: at org.eclipse.jetty.server.handler.AbstractHandler.doStart(AbstractHandler.java:113)
[INFO] GCLOUD: at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
[INFO] GCLOUD: at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:167)
[INFO] GCLOUD: at org.eclipse.jetty.server.Server.start(Server.java:418)
[INFO] GCLOUD: at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:110)
[INFO] GCLOUD: at org.eclipse.jetty.server.handler.AbstractHandler.doStart(AbstractHandler.java:113)
[INFO] GCLOUD: at org.eclipse.jetty.server.Server.doStart(Server.java:382)
[INFO] GCLOUD: at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
[INFO] GCLOUD: at com.google.appengine.tools.development.jetty9.JettyContainerService.startContainer(JettyContainerService.java:343)
[INFO] GCLOUD: at com.google.appengine.tools.development.AbstractContainerService.startup(AbstractContainerService.java:283)
[INFO] GCLOUD: at com.google.appengine.tools.development.AutomaticInstanceHolder.startUp(AutomaticInstanceHolder.java:26)
[INFO] GCLOUD: at com.google.appengine.tools.development.AbstractModule.startup(AbstractModule.java:87)
[INFO] GCLOUD: at com.google.appengine.tools.development.Modules.startup(Modules.java:105)
[INFO] GCLOUD: at com.google.appengine.tools.development.DevAppServerImpl.doStart(DevAppServerImpl.java:282)
[INFO] GCLOUD: at com.google.appengine.tools.development.DevAppServerImpl.access$000(DevAppServerImpl.java:47)
[INFO] GCLOUD: at com.google.appengine.tools.development.DevAppServerImpl$1.run(DevAppServerImpl.java:223)
[INFO] GCLOUD: at com.google.appengine.tools.development.DevAppServerImpl$1.run(DevAppServerImpl.java:221)
[INFO] GCLOUD: at java.security.AccessController.doPrivileged(Native Method)
[INFO] GCLOUD: at com.google.appengine.tools.development.DevAppServerImpl.start(DevAppServerImpl.java:221)
[INFO] GCLOUD: at com.google.appengine.tools.development.DevAppServerMain$StartAction.apply(DevAppServerMain.java:404)
[INFO] GCLOUD: at com.google.appengine.tools.util.Parser$ParseResult.applyArgs(Parser.java:45)
[INFO] GCLOUD: at com.google.appengine.tools.development.DevAppServerMain.run(DevAppServerMain.java:257)
[INFO] GCLOUD: at com.google.appengine.tools.development.DevAppServerMain.main(DevAppServerMain.java:248)
[INFO] GCLOUD: Caused by:
[INFO] GCLOUD: java.lang.ClassNotFoundException: org.hibernate.jpa.HibernateEntityManagerFactory
[INFO] GCLOUD: at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
[INFO] GCLOUD: at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
[INFO] GCLOUD: at com.google.appengine.tools.development.IsolatedAppClassLoader.loadClass(IsolatedAppClassLoader.java:208)
[INFO] GCLOUD: at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
[INFO] GCLOUD: at org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter.<init>(HibernateJpaVendorAdapter.java:82)
[INFO] GCLOUD: at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
[INFO] GCLOUD: at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
[INFO] GCLOUD: at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
[INFO] GCLOUD: at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
[INFO] GCLOUD: at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:172)
[INFO] GCLOUD: at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:87)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1295)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1197)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:555)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515)
[INFO] GCLOUD: at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:346)
[INFO] GCLOUD: at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:124)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1681)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1433)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:592)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320)
[INFO] GCLOUD: at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318)
[INFO] GCLOUD: at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
[INFO] GCLOUD: at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1105)
[INFO] GCLOUD: at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:867)
[INFO] GCLOUD: at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:549)
[INFO] GCLOUD: at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:400)
[INFO] GCLOUD: at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:291)
[INFO] GCLOUD: at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:103)
[INFO] GCLOUD: at org.eclipse.jetty.server.handler.ContextHandler.callContextInitialized(ContextHandler.java:957)
[INFO] GCLOUD: at org.eclipse.jetty.servlet.ServletContextHandler.callContextInitialized(ServletContextHandler.java:553)
[INFO] GCLOUD: at org.eclipse.jetty.server.handler.ContextHandler.startContext(ContextHandler.java:922)
[INFO] GCLOUD: at org.eclipse.jetty.servlet.ServletContextHandler.startContext(ServletContextHandler.java:365)
[INFO] GCLOUD: at org.eclipse.jetty.webapp.WebAppContext.startWebapp(WebAppContext.java:1497)
[INFO] GCLOUD: at org.eclipse.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1459)
[INFO] GCLOUD: at org.eclipse.jetty.server.handler.ContextHandler.doStart(ContextHandler.java:852)
[INFO] GCLOUD: at org.eclipse.jetty.servlet.ServletContextHandler.doStart(ServletContextHandler.java:278)
[INFO] GCLOUD: at org.eclipse.jetty.webapp.WebAppContext.doStart(WebAppContext.java:545)
[INFO] GCLOUD: at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
[INFO] GCLOUD: at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:167)
[INFO] GCLOUD: at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:110)
[INFO] GCLOUD: at org.eclipse.jetty.server.handler.AbstractHandler.doStart(AbstractHandler.java:113)
[INFO] GCLOUD: at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
[INFO] GCLOUD: at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:167)
[INFO] GCLOUD: at org.eclipse.jetty.server.Server.start(Server.java:418)
[INFO] GCLOUD: at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:110)
[INFO] GCLOUD: at org.eclipse.jetty.server.handler.AbstractHandler.doStart(AbstractHandler.java:113)
[INFO] GCLOUD: at org.eclipse.jetty.server.Server.doStart(Server.java:382)
[INFO] GCLOUD: at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
[INFO] GCLOUD: at com.google.appengine.tools.development.jetty9.JettyContainerService.startContainer(JettyContainerService.java:343)
[INFO] GCLOUD: at com.google.appengine.tools.development.AbstractContainerService.startup(AbstractContainerService.java:283)
[INFO] GCLOUD: at com.google.appengine.tools.development.AutomaticInstanceHolder.startUp(AutomaticInstanceHolder.java:26)
[INFO] GCLOUD: at com.google.appengine.tools.development.AbstractModule.startup(AbstractModule.java:87)
[INFO] GCLOUD: at com.google.appengine.tools.development.Modules.startup(Modules.java:105)
[INFO] GCLOUD: at com.google.appengine.tools.development.DevAppServerImpl.doStart(DevAppServerImpl.java:282)
[INFO] GCLOUD: at com.google.appengine.tools.development.DevAppServerImpl.access$000(DevAppServerImpl.java:47)
[INFO] GCLOUD: at com.google.appengine.tools.development.DevAppServerImpl$1.run(DevAppServerImpl.java:223)
[INFO] GCLOUD: at com.google.appengine.tools.development.DevAppServerImpl$1.run(DevAppServerImpl.java:221)
[INFO] GCLOUD: at java.security.AccessController.doPrivileged(Native Method)
[INFO] GCLOUD: at com.google.appengine.tools.development.DevAppServerImpl.start(DevAppServerImpl.java:221)
[INFO] GCLOUD: at com.google.appengine.tools.development.DevAppServerMain$StartAction.apply(DevAppServerMain.java:404)
[INFO] GCLOUD: at com.google.appengine.tools.util.Parser$ParseResult.applyArgs(Parser.java:45)
[INFO] GCLOUD: at com.google.appengine.tools.development.DevAppServerMain.run(DevAppServerMain.java:257)
[INFO] GCLOUD: at com.google.appengine.tools.development.DevAppServerMain.main(DevAppServerMain.java:248)
[INFO] GCLOUD: 2019-09-24 15:17:56.178:INFO:oejs.session:main: DefaultSessionIdManager workerName=node0
[INFO] GCLOUD: 2019-09-24 15:17:56.178:INFO:oejs.session:main: node0 Scavenging disabled
[INFO] GCLOUD: 2019-09-24 15:17:56.204:INFO:oejs.AbstractConnector:main: Started NetworkTrafficSelectChannelConnector@56235b8e{HTTP/1.1,[http/1.1]}{localhost:8080}
[INFO] GCLOUD: 2019-09-24 15:17:56.206:INFO:oejs.Server:main: Started @8847ms
[INFO] GCLOUD: Sep 24, 2019 9:47:56 AM com.google.appengine.tools.development.AbstractModule startup
[INFO] GCLOUD: INFO: Module instance default is running at http://localhost:8080/
[INFO] GCLOUD: Sep 24, 2019 9:47:56 AM com.google.appengine.tools.development.AbstractModule startup
[INFO] GCLOUD: INFO: The admin console is running at http://localhost:8080/_ah/admin
[INFO] GCLOUD: Sep 24, 2019 3:17:56 PM com.google.appengine.tools.development.DevAppServerImpl doStart
[INFO] GCLOUD: INFO: Dev App Server is now running
我知道这是一个非常古老的问题，但是由于我面临同样的问题，这可能与Java版本问题有关。您的休眠版本可能与您当前的 JRE 不兼容，这就是找不到 HibernateEntityManagerFactory 的原因。
我希望这个答案能有所帮助。