problem with EJB 3

I have problem with EJB,i can do normally when current day , and i try change to next 2 day it means current is 9--> 11 . And do somewhere on JSF page such as click on one link or comment one post. . . if current day it work well, but next 2 day . Server log print

INFO: Communication failure detected when attempting to perform read query outside of a transaction. Attempting to retry query.

and after that it throw a long stracktrace such as:

WARNING: Local Exception Stack: 
Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.0.1.v20100213-r6600): org.eclipse.persistence.exceptions.DatabaseException
Internal Exception: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet successfully received from the server was 259,224,647 milliseconds ago.  The last packet sent successfully to the server was 0 milliseconds ago.
Error Code: 0
Call: SELECT itemid, item_name, item_describe, status, img, toprent, author, price, dateexp, item_detail, instock, fine, cat_id FROM item
Query: ReadAllQuery(name="Items.findAll" referenceClass=Items sq开发者_高级运维l="SELECT itemid, item_name, item_describe, status, img, toprent, author, price, dateexp, item_detail, instock, fine, cat_id FROM item")
        at org.eclipse.persistence.exceptions.DatabaseException.sqlException(DatabaseException.java:333)
        at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.processExceptionForCommError(DatabaseAccessor.java:1422)
        at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.basicExecuteCall(DatabaseAccessor.java:679)
        at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.executeCall(DatabaseAccessor.java:530)
        at org.eclipse.persistence.sessions.server.ServerSession.executeCall(ServerSession.java:529)
        at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeCall(DatasourceCallQueryMechanism.java:205)
        at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeCall(DatasourceCallQueryMechanism.java:191)
        at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeSelectCall(DatasourceCallQueryMechanism.java:262)
        at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.selectAllRows(DatasourceCallQueryMechanism.java:618)
        at org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.selectAllRowsFromTable(ExpressionQueryMechanism.java:2537)
        at org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.selectAllRows(ExpressionQueryMechanism.java:2496)
        at org.eclipse.persistence.queries.ReadAllQuery.executeObjectLevelReadQuery(ReadAllQuery.java:455)
        at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeDatabaseQuery(ObjectLevelReadQuery.java:997)
        at org.eclipse.persistence.queries.DatabaseQuery.execute(DatabaseQuery.java:675)
        at org.eclipse.persistence.queries.ObjectLevelReadQuery.execute(ObjectLevelReadQuery.java:958)
        at org.eclipse.persistence.queries.ReadAllQuery.execute(ReadAllQuery.java:432)
        at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeInUnitOfWork(ObjectLevelReadQuery.java:1021)
        at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.internalExecuteQuery(UnitOfWorkImpl.java:2857)
        at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1225)
        at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1299)
        at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1299)
        at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1299)
        at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1299)
        at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1207)
        at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1181)
        at org.eclipse.persistence.internal.jpa.EJBQueryImpl.executeReadQuery(EJBQueryImpl.java:453)
        at org.eclipse.persistence.internal.jpa.EJBQueryImpl.getResultList(EJBQueryImpl.java:681)
        at com.DAO.ItemDAO.retrieveAllItem(ItemDAO.java:43)
        at sun.reflect.GeneratedMethodAccessor129.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.glassfish.ejb.security.application.EJBSecurityManager.runMethod(EJBSecurityManager.java:1056)
        at org.glassfish.ejb.security.application.EJBSecurityManager.invoke(EJBSecurityManager.java:1128)
        at com.sun.ejb.containers.BaseContainer.invokeBeanMethod(BaseContainer.java:5292)
        at com.sun.ejb.EjbInvocation.invokeBeanMethod(EjbInvocation.java:615)
        at com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:797)
        at com.sun.ejb.EjbInvocation.proceed(EjbInvocation.java:567)
        at com.sun.ejb.containers.interceptors.SystemInterceptorProxy.doAround(SystemInterceptorProxy.java:157)
        at com.sun.ejb.containers.interceptors.SystemInterceptorProxy.aroundInvoke(SystemInterceptorProxy.java:139)
        at sun.reflect.GeneratedMethodAccessor98.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at com.sun.ejb.containers.interceptors.AroundInvokeInterceptor.intercept(InterceptorManager.java:858)
        at com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:797)
        at com.sun.ejb.containers.interceptors.InterceptorManager.intercept(InterceptorManager.java:367)
        at com.sun.ejb.containers.BaseContainer.__intercept(BaseContainer.java:5264)
        at com.sun.ejb.containers.BaseContainer.intercept(BaseContainer.java:5252)
        at com.sun.ejb.containers.EJBLocalObjectInvocationHandler.invoke(EJBLocalObjectInvocationHandler.java:190)
        at com.sun.ejb.containers.EJBLocalObjectInvocationHandlerDelegate.invoke(EJBLocalObjectInvocationHandlerDelegate.java:84)
        at $Proxy141.retrieveAllItem(Unknown Source)
        at com.DAO.__EJB31_Generated__ItemDAO__Intf____Bean__.retrieveAllItem(Unknown Source)
        at com.mcgraw.controller.ItemController.getAllItem(ItemController.java:49)
        at sun.reflect.GeneratedMethodAccessor128.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at javax.el.BeanELResolver.getValue(BeanELResolver.java:302)
        at javax.el.CompositeELResolver.getValue(CompositeELResolver.java:175)
        at com.sun.faces.el.FacesCompositeELResolver.getValue(FacesCompositeELResolver.java:72)
        at com.sun.el.parser.AstValue.getValue(AstValue.java:116)
        at com.sun.el.parser.AstValue.getValue(AstValue.java:163)
        at com.sun.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:219)
        at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:102)
        at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:190)
        at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:178)
        at javax.faces.component.UIData.getValue(UIData.java:554)
        at javax.faces.component.UIData.getDataModel(UIData.java:1248)
        at javax.faces.component.UIData.setRowIndex(UIData.java:447)
        at org.primefaces.component.datagrid.DataGridRenderer.encodeTable(DataGridRenderer.java:156)
        at org.primefaces.component.datagrid.DataGridRenderer.encodeMarkup(DataGridRenderer.java:76)
        at org.primefaces.component.datagrid.DataGridRenderer.encodeEnd(DataGridRenderer.java:52)
        at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:878)
        at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1620)
        at javax.faces.render.Renderer.encodeChildren(Renderer.java:168)
        at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:848)
        at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1613)
        at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1616)
        at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1616)
        at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:380)
        at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:126)
        at com.ocpsoft.pretty.faces.application.PrettyViewHandler.renderView(PrettyViewHandler.java:157)
        at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:127)
        at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
        at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
        at javax.faces.webapp.FacesServlet.service(FacesServlet.java:313)
        at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1523)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:343)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:215)
        at com.ocpsoft.pretty.PrettyFilter.doFilter(PrettyFilter.java:113)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.ApplicationDispatcher.doInvoke(ApplicationDispatcher.java:820)
        at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:684)
        at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:517)
        at org.apache.catalina.core.ApplicationDispatcher.doDispatch(ApplicationDispatcher.java:488)
        at org.apache.catalina.core.ApplicationDispatcher.dispatch(ApplicationDispatcher.java:379)
        at org.apache.catalina.core.ApplicationDispatcher.dispatch(ApplicationDispatcher.java:336)
        at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:314)
        at com.ocpsoft.pretty.PrettyFilter.doFilter(PrettyFilter.java:104)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:215)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:277)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:188)
        at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:641)
        at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:97)
        at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:85)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:185)
        at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:325)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:226)
        at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:165)
        at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:791)
        at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:693)
        at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:954)
        at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:170)
        at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:135)
        at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:102)
        at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:88)
        at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:76)
        at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:53)
        at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:57)
        at com.sun.grizzly.ContextTask.run(ContextTask.java:69)
        at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:330)
        at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:309)
        at java.lang.Thread.run(Thread.java:619)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet successfully received from the server was 259,224,647 milliseconds ago.  The last packet sent successfully to the server was 0 milliseconds ago.
        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 com.mysql.jdbc.Util.handleNewInstance(Util.java:409)
        at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1118)
        at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3055)
        at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2941)
        at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3489)
        at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1959)
        at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2113)
        at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2568)
        at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2113)
        at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2275)
        at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.executeSelect(DatabaseAccessor.java:892)
        at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.basicExecuteCall(DatabaseAccessor.java:602)
        ... 120 more
Caused by: java.io.EOFException: Can not read response from server. Expected to read 4 bytes, read 0 bytes before connection was unexpectedly lost.
        at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:2502)
        at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2952)
        ... 129 more

i don't know why error occur, any body please help me !!!

Thank you

Your database (mysql) has gone down or has problems handling connections. Make sure mysql is running and that you have enough resources (RAM, CPU).

You connection pool might be configured to timeout idle connections after some time (and is maybe not configured to renew them).

If it isn't, MySQL does timeout idle connections after 8 hours by default (the famous wait_timeout).

In both cases, I'm not sure doing time jumps while servers are up (including your app server) is a very good idea, you're looking for troubles (and you found them).