org.hibernate.exception.JDBCConnectionException: Could not open connection exception in MySQL

Question

I have setup a mysql instance onto my local machine and using it with my java hibernate application on GAE. It was perfectly working, but since the afternoon it has started giving me error given below. Please help me figure out how to fix this. I am stuck and cannot proceed in code without any db transactions. Thanks!

org.hibernate.exception.JDBCConnectionException: Could not open connection
    at org.hibernate.exception.internal.SQLStateConversionDelegate.convert(SQLStateConversionDelegate.java:131)
    at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:49)
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:125)
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:110)
    at org.hibernate.engine.jdbc.internal.LogicalConnectionImpl.obtainConnection(LogicalConnectionImpl.java:304)
    at org.hibernate.engine.jdbc.internal.LogicalConnectionImpl.getConnection(LogicalConnectionImpl.java:169)
    at org.hibernate.engine.jdbc.internal.proxy.ConnectionProxyHandler.extractPhysicalConnection(ConnectionProxyHandler.java:82)
    at org.hibernate.engine.jdbc.internal.proxy.ConnectionProxyHandler.continueInvocation(ConnectionProxyHandler.java:138)
    at org.hibernate.engine.jdbc.internal.proxy.AbstractProxyHandler.invoke(AbstractProxyHandler.java:81)
    at com.sun.proxy.$Proxy47.prepareStatement(Unknown Source)
    at org.hibernate.engine.jdbc.internal.StatementPreparerImpl$5.doPrepare(StatementPreparerImpl.java:147)
    at org.hibernate.engine.jdbc.internal.StatementPreparerImpl$StatementPreparationTemplate.prepareStatement(StatementPreparerImpl.java:166)
    at org.hibernate.engine.jdbc.internal.StatementPreparerImpl.prepareQueryStatement(StatementPreparerImpl.java:145)
    at org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:1711)
    at org.hibernate.loader.Loader.doQuery(Loader.java:828)
    at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:289)
    at org.hibernate.loader.Loader.doList(Loader.java:2438)
    at org.hibernate.loader.Loader.doList(Loader.java:2424)
    at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2254)
    at org.hibernate.loader.Loader.list(Loader.java:2249)
    at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:470)
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:355)
    at org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:195)
    at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1248)
    at org.hibernate.internal.QueryImpl.list(QueryImpl.java:101)
    at com.bullbeardevice.dao.impl.UserManagementDAOImpl.getUserRegistrationList(UserManagementDAOImpl.java:39)
    at com.bullbeardevice.service.impl.UserManagementServiceImpl.checkUserAlreadyRegistered(UserManagementServiceImpl.java:111)
    at com.bullbeardevice.controller.user.UserManagementController.registerUser(UserManagementController.java:38)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at com.google.appengine.tools.development.agent.runtime.Runtime.invoke(Runtime.java:115)
    at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:219)
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:100)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:604)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:565)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:923)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882)
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:789)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166)
    at org.springframework.orm.hibernate4.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:119)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.google.appengine.api.socket.dev.DevSocketFilter.doFilter(DevSocketFilter.java:74)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.google.appengine.tools.development.ResponseRewriterFilter.doFilter(ResponseRewriterFilter.java:127)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.google.appengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:34)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java:63)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFileFilter.java:125)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.google.appengine.tools.development.DevAppServerModulesFilter.doDirectRequest(DevAppServerModulesFilter.java:366)
    at com.google.appengine.tools.development.DevAppServerModulesFilter.doDirectModuleRequest(DevAppServerModulesFilter.java:349)
    at com.google.appengine.tools.development.DevAppServerModulesFilter.doFilter(DevAppServerModulesFilter.java:116)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388)
    at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
    at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
    at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)
    at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418)
    at com.google.appengine.tools.development.DevAppEngineWebAppContext.handle(DevAppEngineWebAppContext.java:98)
    at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
    at com.google.appengine.tools.development.JettyContainerService$ApiProxyHandler.handle(JettyContainerService.java:490)
    at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
    at org.mortbay.jetty.Server.handle(Server.java:326)
    at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
    at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:938)
    at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:755)
    at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218)
    at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
    at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409)
    at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

Last packet sent to the server was 0 ms ago.
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
    at com.google.appengine.tools.development.agent.runtime.Runtime.newInstance_(Runtime.java:127)
    at com.google.appengine.tools.development.agent.runtime.Runtime.newInstance(Runtime.java:135)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
    at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2103)
    at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:718)
    at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
    at com.google.appengine.tools.development.agent.runtime.Runtime.newInstance_(Runtime.java:127)
    at com.google.appengine.tools.development.agent.runtime.Runtime.newInstance(Runtime.java:135)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
    at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:302)
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:282)
    at java.sql.DriverManager.getConnection(DriverManager.java:571)
    at java.sql.DriverManager.getConnection(DriverManager.java:187)
    at org.springframework.jdbc.datasource.DriverManagerDataSource.getConnectionFromDriverManager(DriverManagerDataSource.java:173)
    at org.springframework.jdbc.datasource.DriverManagerDataSource.getConnectionFromDriver(DriverManagerDataSource.java:164)
    at org.springframework.jdbc.datasource.AbstractDriverBasedDataSource.getConnectionFromDriver(AbstractDriverBasedDataSource.java:149)
    at org.springframework.jdbc.datasource.AbstractDriverBasedDataSource.getConnection(AbstractDriverBasedDataSource.java:119)
    at org.hibernate.service.jdbc.connections.internal.DatasourceConnectionProviderImpl.getConnection(DatasourceConnectionProviderImpl.java:141)
    at org.hibernate.internal.AbstractSessionImpl$NonContextualJdbcConnectionAccess.obtainConnection(AbstractSessionImpl.java:281)
    at org.hibernate.engine.jdbc.internal.LogicalConnectionImpl.obtainConnection(LogicalConnectionImpl.java:297)
    ... 78 more
Caused by: java.net.SocketException: Socket operation timed out: The API call remote_socket.CreateSocket() took too long to respond and was cancelled.
    at com.google.appengine.api.socket.SocketApiHelper.makeSyncCall(SocketApiHelper.java:73)
    at com.google.appengine.api.socket.AppEngineSocketImpl.createSocket(AppEngineSocketImpl.java:466)
    at com.google.appengine.api.socket.AppEngineSocketImpl.connectToAddress(AppEngineSocketImpl.java:340)
    at com.google.appengine.api.socket.AppEngineSocketImpl.connect(AppEngineSocketImpl.java:332)
    at java.net.Socket.connect(Socket.java:579)
    at java.net.Socket.connect(Socket.java:528)
    at java.net.Socket.<init>(Socket.java:425)
    at java.net.Socket.<init>(Socket.java:241)
    at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:253)
    at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:280)
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2026)







<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context"
        xmlns:jee="http://www.springframework.org/schema/jee" xmlns:tx="http://www.springframework.org/schema/tx"
        xsi:schemaLocation="
            http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
            http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd
            http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-2.5.xsd
            http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd">

<context:component-scan base-package="com.bullbeardevice.*" /> 


  <!-- Hibernate Session Factory -->
<bean id="propertyConfigurer"
        class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
        <property name="locations">
            <list>
                <value>classpath:database.properties</value>
            </list>
        </property>
    </bean>

    <bean id="dataSource"
        class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="${db.driverClassName}" />
        <property name="url" value="${db.url}" />
        <property name="username" value="${db.username}" />
        <property name="password" value="${db.password}" />
    </bean>

    <bean id="sessionFactory"
        class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
        <property name="dataSource" ref="dataSource" />
        <property name="packagesToScan" value="com.bullbeardevice.model" />
        <property name="hibernateProperties">
            <props>
            <prop key="hibernate.dialect">${hibernate.dialect}</prop>
                <prop key="hibernate.show_sql">${hibernate.show_sql}</prop>
                <prop key="hibernate.jdbc.batch_size">100</prop>
                <!-- <prop key="hibernate.hbm2ddl.auto">create-drop</prop>  -->
                <prop key="hibernate.current_session_context_class">
                    org.springframework.orm.hibernate4.SpringSessionContext
                </prop>
                <!-- configuration pool via c3p0 -->
                <prop key="hibernate.c3p0.acquire_increment">5</prop>
                <prop key="hibernate.c3p0.idle_test_period">600</prop>
                <prop key="hibernate.c3p0.max_size">25</prop>
                <prop key="hibernate.c3p0.max_statements">25</prop>
                <prop key="hibernate.c3p0.min_size">5</prop>
                <prop key="hibernate.c3p0.timeout">300</prop>
                <prop key="hibernate.connection.release_mode">auto</prop>
                <prop key="hibernate.auto_close_session">true</prop>
            </props>
        </property>
    </bean>
    <bean id="transactionManager"
        class="org.springframework.orm.hibernate4.HibernateTransactionManager">
        <property name="sessionFactory" ref="sessionFactory" />
    </bean>
  <tx:annotation-driven transaction-manager="transactionManager"/>

  </beans>

db.driverClassName=com.mysql.jdbc.Driver
#db.url=jdbc:mysql://192.168.1.2:3306/bullbeardevice
db.url=jdbc:mysql://localhost:3306/bullbeardevice
#db.url=jdbc:Oracle:thin:@127.0.0.1:1521/XE
db.username=bullbeardevice
db.password=bullbeardevice
#hibernate.dialect=org.hibernate.dialect.MySQL5Dialect
hibernate.dialect=org.hibernate.dialect.MySQLDialect
hibernate.show_sql=true
hibernate.cache.use_second_level_cache=false
hibernate.cache.use_query_cache=false
#hibernate.cache.provider_class=net.sf.ehcache.hibernate.EhCacheProvider
#hibernate.cache.provider_class==org.hibernate.cache.EhCacheProvider
#db.sid=XE
# configuration for hibernate search
hibernate.search.default.locking_strategy=simple
#hibernate.search.analyzer=org.apache.lucene.analysis.en.EnglishAnalyzer
hibernate.search.worker.batch_size=100
hibernate.search.indexing_strategy = manual
hibernate.search.default.reader.strategy = shared
hibernate.search.default.worker.thread_pool.size=30
hibernate.search.default.indexwriter.ram_buffer_size=10
hibernate.search.default.indexwriter.merge_max_optimize_size=7
hibernate.search.default.indexwriter.merge_max_size=7

Answer 1

As it clearly says in exception cause:

Caused by: java.net.SocketException: Socket operation timed out: The API call remote_socket.CreateSocket() took too long to respond and was cancelled.

That it waited till it could connect but it couldn't so it reached the timeout and stopped waiting to connect.

If you can connect with other software that means that you have some hibernate config problems.

You need to fix your hibernate configuration files.

A typical hibernate configuration file:

<?xml version="1.0" encoding="UTF-8"?>  
<!DOCTYPE hibernate-configuration PUBLIC  
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"  
        "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">  
<hibernate-configuration>  
    <session-factory>  
        <property name="hibernate.connection.driver_class">org.hsqldb.jdbcDriver</property>  
        <property name="hibernate.connection.url">jdbc:hsqldb:hsql://localhost/xdb</property>  
        <property name="hibernate.connection.username">sa</property>  
        <property name="connection.password">krishna</property>  
        <property name="connection.pool_size">1</property>  
        <property name="hibernate.dialect">org.hibernate.dialect.HSQLDialect</property>  
        <property name="show_sql">true</property>  
        <property name="hbm2ddl.auto">create</property>  
        <mapping resource="com/vaannila/student/Student.hbm.xml"/>  
        <mapping resource="com/vaannila/student/Address.hbm.xml"/>  
    </session-factory>  
</hibernate-configuration> 

Try to start the database in server mode:

org.hsqldb.server.Server -database.0 file:mydb -dbname.0 xdb // <- Notice what is here