hibernate - google cloudsql + google app engine + spring mvc + hierbnate/jpa error -

i have problem cloudsql , hibernates connections,i use spring mvc 3 google app engine , hibernate / jpa. here loggs in gap console :

uncaught exception servlet org.springframework.transaction.cannotcreatetransactionexception: not open jpa entitymanager transaction; nested exception javax.persistence.persistenceexception: org.hibernate.exception.jdbcconnectionexception: not open connection @ org.springframework.orm.jpa.jpatransactionmanager.dobegin(jpatransactionmanager.java:427) @ org.springframework.transaction.support.abstractplatformtransactionmanager.gettransaction(abstractplatformtransactionmanager.java:371) @ org.springframework.transaction.interceptor.transactionaspectsupport.createtransactionifnecessary(transactionaspectsupport.java:335) @ org.springframework.transaction.interceptor.transactioninterceptor.invoke(transactioninterceptor.java:105) @ org.springframework.aop.framework.reflectivemethodinvocation.proceed(reflectivemethodinvocation.java:172) @ org.springframework.dao.support.persistenceexceptiontranslationinterceptor.invoke(persistenceexceptiontranslationinterceptor.java:155) @ org.springframework.aop.framework.reflectivemethodinvocation.proceed(reflectivemethodinvocation.java:172) @ org.springframework.aop.framework.jdkdynamicaopproxy.invoke(jdkdynamicaopproxy.java:202) @ sun.proxy.$proxy55.findall(unknown source) @ com.********************r.getcountrylist(generalcontroller.java:36) @ sun.reflect.nativemethodaccessorimpl.invoke0(native method) @ sun.reflect.nativemethodaccessorimpl.invoke(nativemethodaccessorimpl.java:57) @ sun.reflect.delegatingmethodaccessorimpl.invoke(delegatingmethodaccessorimpl.java:43) @ java.lang.reflect.method.invoke(method.java:45) @ org.springframework.web.method.support.invocablehandlermethod.invoke(invocablehandlermethod.java:213) @ org.springframework.web.method.support.invocablehandlermethod.invokeforrequest(invocablehandlermethod.java:126) @ org.springframework.web.servlet.mvc.method.annotation.servletinvocablehandlermethod.invokeandhandle(servletinvocablehandlermethod.java:96) @ org.springframework.web.servlet.mvc.method.annotation.requestmappinghandleradapter.invokehandlermethod(requestmappinghandleradapter.java:617) @ org.springframework.web.servlet.mvc.method.annotation.requestmappinghandleradapter.handleinternal(requestmappinghandleradapter.java:578) @ org.springframework.web.servlet.mvc.method.abstracthandlermethodadapter.handle(abstracthandlermethodadapter.java:80) @ org.springframework.web.servlet.dispatcherservlet.dodispatch(dispatcherservlet.java:923) @ org.springframework.web.servlet.dispatcherservlet.doservice(dispatcherservlet.java:852) @ org.springframework.web.servlet.frameworkservlet.processrequest(frameworkservlet.java:882) @ org.springframework.web.servlet.frameworkservlet.doget(frameworkservlet.java:778) @ javax.servlet.http.httpservlet.service(httpservlet.java:617) @ javax.servlet.http.httpservlet.service(httpservlet.java:717) @ org.mortbay.jetty.servlet.servletholder.handle(servletholder.java:511) @ org.mortbay.jetty.servlet.servlethandler$cachedchain.dofilter(servlethandler.java:1166) @ org.mortbay.jetty.servlet.servlethandler$cachedchain.dofilter(servlethandler.java:1157) @ org.mortbay.jetty.servlet.servlethandler$cachedchain.dofilter(servlethandler.java:1157) @ org.mortbay.jetty.servlet.servlethandler$cachedchain.dofilter(servlethandler.java:1157) @ org.mortbay.jetty.servlet.servlethandler.handle(servlethandler.java:388) @ org.mortbay.jetty.security.securityhandler.handle(securityhandler.java:216) @ org.mortbay.jetty.servlet.sessionhandler.handle(sessionhandler.java:182) @ org.mortbay.jetty.handler.contexthandler.handle(contexthandler.java:765) @ org.mortbay.jetty.webapp.webappcontext.handle(webappcontext.java:418) @ org.mortbay.jetty.handler.handlerwrapper.handle(handlerwrapper.java:152) @ org.mortbay.jetty.server.handle(server.java:326) @ org.mortbay.jetty.httpconnection.handlerequest(httpconnection.java:542) @ org.mortbay.jetty.httpconnection$requesthandler.headercomplete(httpconnection.java:923) @ org.mortbay.jetty.httpconnection.handle(httpconnection.java:404) @ com.google.tracing.tracecontext$tracecontextrunnable.runincontext(tracecontext.java:435) @ com.google.tracing.tracecontext$tracecontextrunnable$1.run(tracecontext.java:442) @ com.google.tracing.currentcontext.runincontext(currentcontext.java:186) @ com.google.tracing.tracecontext$abstracttracecontextcallback.runininheritedcontextnounref(tracecontext.java:306) @ com.google.tracing.tracecontext$abstracttracecontextcallback.runininheritedcontext(tracecontext.java:298) @ com.google.tracing.tracecontext$tracecontextrunnable.run(tracecontext.java:439) @ java.lang.thread.run(thread.java:722) caused by: javax.persistence.persistenceexception: org.hibernate.exception.jdbcconnectionexception: not open connection @ org.hibernate.ejb.abstractentitymanagerimpl.convert(abstractentitymanagerimpl.java:1361) @ org.hibernate.ejb.abstractentitymanagerimpl.convert(abstractentitymanagerimpl.java:1289) @ org.hibernate.ejb.abstractentitymanagerimpl.throwpersistenceexception(abstractentitymanagerimpl.java:1371) @ org.hibernate.ejb.transactionimpl.begin(transactionimpl.java:60) @ org.springframework.orm.jpa.defaultjpadialect.begintransaction(defaultjpadialect.java:70) @ org.springframework.orm.jpa.vendor.hibernatejpadialect.begintransaction(hibernatejpadialect.java:59) @ org.springframework.orm.jpa.jpatransactionmanager.dobegin(jpatransactionmanager.java:377) ... 47 more caused by: org.hibernate.exception.jdbcconnectionexception: not open connection @ org.hibernate.exception.internal.sqlstateconversiondelegate.convert(sqlstateconversiondelegate.java:131) @ org.hibernate.exception.internal.standardsqlexceptionconverter.convert(standardsqlexceptionconverter.java:47) @ org.hibernate.engine.jdbc.spi.sqlexceptionhelper.convert(sqlexceptionhelper.java:125) @ org.hibernate.engine.jdbc.spi.sqlexceptionhelper.convert(sqlexceptionhelper.java:110) @ org.hibernate.engine.jdbc.internal.logicalconnectionimpl.obtainconnection(logicalconnectionimpl.java:304) @ org.hibernate.engine.jdbc.internal.logicalconnectionimpl.getconnection(logicalconnectionimpl.java:169) @ org.hibernate.engine.transaction.internal.jdbc.jdbctransaction.dobegin(jdbctransaction.java:67) @ org.hibernate.engine.transaction.spi.abstracttransactionimpl.begin(abstracttransactionimpl.java:160) @ org.hibernate.internal.sessionimpl.begintransaction(sessionimpl.java:1263) @ org.hibernate.ejb.transactionimpl.begin(transactionimpl.java:57) ... 50 more caused by: com.mysql.jdbc.exceptions.jdbc4.communicationsexception: communications link failure last packet sent server 0 milliseconds ago. driver has not received packets server. @ sun.reflect.nativeconstructoraccessorimpl.newinstance0(native method) @ sun.reflect.nativeconstructoraccessorimpl.newinstance(nativeconstructoraccessorimpl.java:57) @ sun.reflect.delegatingconstructoraccessorimpl.newinstance(delegatingconstructoraccessorimpl.java:45) @ java.lang.reflect.constructor.newinstance(constructor.java:33) @ com.mysql.jdbc.util.handlenewinstance(util.java:411) @ com.mysql.jdbc.sqlerror.createcommunicationsexception(sqlerror.java:1116) @ com.mysql.jdbc.mysqlio.<init>(mysqlio.java:344) @ com.mysql.jdbc.connectionimpl.coreconnect(connectionimpl.java:2332) @ com.mysql.jdbc.connectionimpl.connectonetryonly(connectionimpl.java:2369) @ com.mysql.jdbc.connectionimpl.createnewio(connectionimpl.java:2153) @ com.mysql.jdbc.connectionimpl.<init>(connectionimpl.java:792) @ com.mysql.jdbc.jdbc4connection.<init>(jdbc4connection.java:47) @ sun.reflect.nativeconstructoraccessorimpl.newinstance0(native method) @ sun.reflect.nativeconstructoraccessorimpl.newinstance(nativeconstructoraccessorimpl.java:57) @ sun.reflect.delegatingconstructoraccessorimpl.newinstance(delegatingconstructoraccessorimpl.java:45) @ java.lang.reflect.constructor.newinstance(constructor.java:33) @ com.mysql.jdbc.util.handlenewinstance(util.java:411) @ com.mysql.jdbc.connectionimpl.getinstance(connectionimpl.java:381) @ co...(length 9240) 

and here config file persistence.xml :

<?xml version="1.0" encoding="utf-8" ?> <persistence xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/xmlschema-instance" xsi:schemalocation="http://java.sun.com/xml/ns/persistence     http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd" version="1.0">  <persistence-unit name="*********" transaction-type="resource_local">     <provider>org.hibernate.ejb.hibernatepersistence</provider>     <class>com.******************</class>      <class>com.******************</class>     <class>com.******************</class>      <class>com.******************</class>      <properties>                   <property name="hibernate.connection.driver_class" value="com.google.appengine.api.rdbms.appenginedriver"/>          <property name="hibernate.connection.url" value="jdbc:google:rdbms://instancename/tablename?zerodatetimebehavior=converttonull"/>         <property name="hibernate.connection.username" value="root"/>         <property name="hibernate.connection.password" value=""/>                  <property name="hibernate.connection.pool_size" value="0" />         <property name="hibernate.hbm2ddl.auto" value="update" />          <property name="hibernate.dialect" value="org.hibernate.dialect.mysqldialect"/>     </properties> </persistence-unit> </persistence> 

servlet-context.xml file :

<?xml version="1.0" encoding="utf-8"?>  <beans:beans xmlns="http://www.springframework.org/schema/mvc" xmlns:xsi="http://www.w3.org/2001/xmlschema-instance"       xmlns:beans="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xmlns:jpa="http://www.springframework.org/schema/data/jpa" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:security="http://www.springframework.org/schema/security" xsi:schemalocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd     http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd     http://www.springframework.org/schema/context   http://www.springframework.org/schema/context/spring-context-3.1.xsd     http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa.xsd      http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd      http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.0.xsd      http://www.springframework.org/schema/security      http://www.springframework.org/schema/security/spring-security-3.1.xsd">  <annotation-driven />  <resources mapping="/resources/**" location="/resources/" /> <context:component-scan base-package="com.*********" />  <beans:bean     class="org.springframework.web.servlet.view.internalresourceviewresolver">     <beans:property name="prefix" value="/web-inf/views/" />     <beans:property name="suffix" value=".jsp" /> </beans:bean>  <beans:bean id="localeresolver"     class="org.springframework.web.servlet.i18n.cookielocaleresolver">     <beans:property name="cookiename" value="languagecookie"></beans:property> </beans:bean>  <interceptors>     <beans:bean id="localechangeinterceptor"         class="org.springframework.web.servlet.i18n.localechangeinterceptor">         <beans:property name="paramname" value="language" />     </beans:bean>  </interceptors>  <beans:bean id="messagesource"     class="org.springframework.context.support.resourcebundlemessagesource">     <beans:property name="basename" value="messages" /> </beans:bean>  <jpa:repositories base-package="com.******************.repositories" /> <tx:annotation-driven transaction-manager="transactionmanager" />  <beans:bean id="hibernateexceptiontranslator"     class="org.springframework.orm.hibernate4.hibernateexceptiontranslator"> </beans:bean>  <beans:bean id="entitymanagerfactory"     class="org.springframework.orm.jpa.localcontainerentitymanagerfactorybean">   <beans:property name="persistencexmllocation" value="classpath:meta-inf/persistence.xml" />           <beans:property name="jpavendoradapter">          <beans:bean             class="org.springframework.orm.jpa.vendor.hibernatejpavendoradapter">             <beans:property name="showsql" value="true" />             <!--beans:property name="generateddl" value="true" /-->             <beans:property name="databaseplatform"                 value="org.hibernate.dialect.mysql5dialect" />           </beans:bean>     </beans:property> </beans:bean> <beans:bean id="transactionmanager"     class="org.springframework.orm.jpa.jpatransactionmanager">     <beans:property name="entitymanagerfactory" ref="entitymanagerfactory" /> </beans:bean>