Не найдено [EntityType] для ключевого класса […] в метамодели

Сущность:

@Entity
@Table(name="user_account")
public class UserAccount implements Serializable{
    private static final long serialVersionUID = -2606506548742732094L;

    @Id
    @GeneratedValue(strategy=GenerationType.TABLE)
    private Integer id;

persistence.xml

<persistence-unit name="Maze" transaction-type="RESOURCE_LOCAL">

    <exclude-unlisted-classes>false</exclude-unlisted-classes>
    <properties>
        <property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver"/>
        <property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/mazedb"/>
        <property name="javax.persistence.jdbc.user" value="root"/>
        <property name="javax.persistence.jdbc.password" value="root"/>
    </properties>

</persistence-unit>

Ошибка

WARNING: #{accountController.performLogin}: java.lang.IllegalArgumentException: No [EntityType] was found for the key class [com.maze.model.UserAccount] in the Metamodel - please verify that the [Entity] class was referenced in persistence.xml using a specific <class>com.maze.model.UserAccount</class> property or a global <exclude-unlisted-classes>false</exclude-unlisted-classes> element.
javax.faces.FacesException: #{accountController.performLogin}: java.lang.IllegalArgumentException: No [EntityType] was found for the key class [com.maze.model.UserAccount] in the Metamodel - please verify that the [Entity] class was referenced in persistence.xml using a specific <class>com.maze.model.UserAccount</class> property or a global <exclude-unlisted-classes>false</exclude-unlisted-classes> element.
    at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:118)
    at javax.faces.component.UICommand.broadcast(UICommand.java:315)
    at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:794)
    at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1259)
    at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
    at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593)
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1539)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
    at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:98)
    at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:91)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:162)
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:330)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:174)
    at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:828)
    at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:725)
    at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1019)
    at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:225)
    at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
    at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
    at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
    at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
    at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
    at java.lang.Thread.run(Thread.java:662)

Поведение Каждый раз, когда я перезапускаю веб-контейнер, все работает нормально в течение нескольких минут, а затем возникает эта ошибка. Что мне не хватает?

РЕДАКТИРОВАТЬ:

Теперь я использую объект в области приложения, и та же ошибка возникает для объекта Country. И Пользователь, и Страна определены как классы в файле persistance.xml. Кроме того, для exclude-unlisted-classes установлено значение false.

SEVERE: Critical error during deployment: 
java.lang.ExceptionInInitializerError
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at     sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39    )
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at java.lang.Class.newInstance0(Class.java:355)
at java.lang.Class.newInstance(Class.java:308)
at com.sun.faces.mgbean.BeanBuilder.newBeanInstance(BeanBuilder.java:188)
at com.sun.faces.mgbean.BeanBuilder.build(BeanBuilder.java:102)
at com.sun.faces.mgbean.BeanManager.createAndPush(BeanManager.java:409)
at com.sun.faces.mgbean.BeanManager.create(BeanManager.java:269)
at com.sun.faces.mgbean.BeanManager.create(BeanManager.java:256)
at com.sun.faces.config.ConfigureListener.contextInitialized(ConfigureListener.java:255)
at org.apache.catalina.core.StandardContext.contextListenerStart(StandardContext.java:4750)
at com.sun.enterprise.web.WebModule.contextListenerStart(WebModule.java:550)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:5366)
at com.sun.enterprise.web.WebModule.start(WebModule.java:498)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:917)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:901)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:733)
at com.sun.enterprise.web.WebContainer.loadWebModule(WebContainer.java:2000)
at com.sun.enterprise.web.WebContainer.loadWebModule(WebContainer.java:1651)
at com.sun.enterprise.web.WebApplication.start(WebApplication.java:109)
at org.glassfish.internal.data.EngineRef.start(EngineRef.java:130)
at org.glassfish.internal.data.ModuleInfo.start(ModuleInfo.java:269)
at org.glassfish.internal.data.ApplicationInfo.start(ApplicationInfo.java:294)
at com.sun.enterprise.v3.server.ApplicationLifecycle.deploy(ApplicationLifecycle.java:462)
at com.sun.enterprise.v3.server.ApplicationLifecycle.deploy(ApplicationLifecycle.java:240)
at org.glassfish.deployment.admin.DeployCommand.execute(DeployCommand.java:382)
at com.sun.enterprise.v3.admin.CommandRunnerImpl$1.execute(CommandRunnerImpl.java:355)
at com.sun.enterprise.v3.admin.CommandRunnerImpl.doCommand(CommandRunnerImpl.java:370)
at com.sun.enterprise.v3.admin.CommandRunnerImpl.doCommand(CommandRunnerImpl.java:1064)
at com.sun.enterprise.v3.admin.CommandRunnerImpl.access$1200(CommandRunnerImpl.java:96)
at com.sun.enterprise.v3.admin.CommandRunnerImpl$ExecutionContext.execute(CommandRunnerImpl.java:1244)
at com.sun.enterprise.v3.admin.CommandRunnerImpl$ExecutionContext.execute(CommandRunnerImpl.java:1232)
at com.sun.enterprise.v3.admin.AdminAdapter.doCommand(AdminAdapter.java:459)
at com.sun.enterprise.v3.admin.AdminAdapter.service(AdminAdapter.java:209)
at com.sun.grizzly.tcp.http11.GrizzlyAdapter.service(GrizzlyAdapter.java:168)
at com.sun.enterprise.v3.server.HK2Dispatcher.dispath(HK2Dispatcher.java:117)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:238)
at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:828)
at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:725)
at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1019)
at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:225)
at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
at java.lang.Thread.run(Thread.java:662)
Caused by: java.lang.IllegalArgumentException: No [EntityType] was found for the key class [com.maze.model.Country] in the Metamodel - please verify that the [Entity] class was referenced in persistence.xml using a specific <class>com.maze.model.Country</class> property or a global <exclude-unlisted-classes>false</exclude-unlisted-classes> element.
at org.eclipse.persistence.internal.jpa.metamodel.MetamodelImpl.entityEmbeddableManagedTypeNotFound(MetamodelImpl.java:174)
at org.eclipse.persistence.internal.jpa.metamodel.MetamodelImpl.entity(MetamodelImpl.java:194)
at org.eclipse.persistence.internal.jpa.querydef.AbstractQueryImpl.from(AbstractQueryImpl.java:97)
at com.maze.service.CountryService.readList(CountryService.java:74)
at com.maze.util.MazeConstants.<clinit>(MazeConstants.java:26)

Объект Country:

@Entity
@Table(name = "country")
public class Country implements Serializable{

private static final long serialVersionUID = 4086034429815316972L;

@Id
private Integer id;
private String name;
private String continent;
private Integer population;
private Float surface;

@OneToMany(mappedBy = "country")
private List<User> userList;

Теперь, когда этот объект используется в области приложения, и объект выдает эту ошибку, Glassfish не запускается полностью.

ВТОРОЕ РЕДАКТИРОВАНИЕ: Исходя из текущего поведения кажется, что веб-контейнер запускается и работает нормально до первого горячего развертывания.