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Hibernate - connecting to remote mysql database fails, when connecting to local succeeds

I have 2 machines with identical databases.
I'm using hibernate version 4.3.6.Final
When I'm using this configuration (connecting to local DB) - everything is ok :
<persistence-unit name="stg">
<provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
<properties>
<!--
<property name="hibernate.ejb.cfgfile" value="/hibernate.cfg.xml"/>
-->
<property name="hibernate.ejb.naming_strategy" value="org.hibernate.cfg.ImprovedNamingStrategy"/>
<property name="hibernate.hbm2ddl.auto" value="update"/>
<property name="hibernate.archive.autodetection" value="class, hbm"/>
<property name="hibernate.show_sql" value="false"/>
<property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver"/>
<property name="hibernate.connection.password" value="PASSWORD"/>
<property name="hibernate.connection.url" value="jdbc:mysql://127.0.0.1:3306/DATABASENAME?autoReconnect=true"/>
<property name="hibernate.connection.username" value="root"/>
<property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>
<property name="hibernate.c3p0.timeout" value="3600"/>
<property name="hibernate.c3p0.min_size" value="20"/>
<property name="hibernate.c3p0.max_size" value="100"/>
<property name="hibernate.c3p0.acquire_increment" value="5"/>
<property name="hibernate.c3p0.maxIdleTimeExcessConnections" value="300"/>
<property name="hibernate.c3p0.automaticTestTable" value="hibernate_conn_test"/>
<property name="hibernate.c3p0.testConnectionOnCheckout" value="false"/>
<property name="hibernate.c3p0.validate" value="false"/>
<property name="hibernate.c3p0.testConnectionOnCheckin" value="true"/>
<property name="hibernate.c3p0.idle_test_period" value="300"/>
<property name="hibernate.c3p0.unreturnedConnectionTimeout" value="3600"/>
<property name="hibernate.c3p0.numHelperThreads" value="6"/>
</properties>
</persistence-unit>
The only thing that I changed is the IP to the other machine , and I always get the same error :
<property name="hibernate.connection.url" value="jdbc:mysql://2.2.2.2:3306/te?autoReconnect=true"/>
This is the errors I'm getting:
[localhost-startStop-1][ ][13 Jan 2016 16:40:43,386] [internal.JdbcServicesImpl ]: [WARN ] HHH000342: Could not obtain connection to query metadata : Could not create connection to database server. Attempted reconnect 3 times. Giving up.
[localhost-startStop-1][ ][13 Jan 2016 16:40:48,819] [hbm2ddl.SchemaUpdate ]: [ERROR] HHH000319: Could not get database metadata
com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.Util.getInstance(Util.java:386)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1015)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:989)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:975)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:920)
at com.mysql.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:2395)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2316)
at com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:834)
at com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:47)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:416)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:347)
at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:131)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:156)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:145)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPoolManager.initializeAutomaticTestTable(C3P0PooledConnectionPoolManager.java:898)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPoolManager.createPooledConnectionPool(C3P0PooledConnectionPoolManager.java:821)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPoolManager.getPool(C3P0PooledConnectionPoolManager.java:331)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPoolManager.getPool(C3P0PooledConnectionPoolManager.java:348)
at com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource.getConnection(AbstractPoolBackedDataSource.java:140)
at org.hibernate.c3p0.internal.C3P0ConnectionProvider.getConnection(C3P0ConnectionProvider.java:89)
at org.hibernate.tool.hbm2ddl.SuppliedConnectionProviderConnectionHelper.prepare(SuppliedConnectionProviderConnectionHelper.java:51)
at org.hibernate.tool.hbm2ddl.SchemaUpdate.execute(SchemaUpdate.java:194)
at org.hibernate.tool.hbm2ddl.SchemaUpdate.execute(SchemaUpdate.java:178)
at org.hibernate.internal.SessionFactoryImpl.(SessionFactoryImpl.java:522)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1857)
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:850)
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:843)
at org.hibernate.boot.registry.classloading.internal.ClassLoaderServiceImpl.withTccl(ClassLoaderServiceImpl.java:398)
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:842)
at org.hibernate.jpa.HibernatePersistenceProvider.createEntityManagerFactory(HibernatePersistenceProvider.java:75)
at com.checkpoint.te.shared.service.CustomHibernatePersistence.createEntityManagerFactory(CustomHibernatePersistence.java:43)
at com.checkpoint.te.shared.service.CustomHibernatePersistence.createEntityManagerFactory(CustomHibernatePersistence.java:28)
at com.checkpoint.te.shared.sql.DbHandler.lifeCycleUp(DbHandler.java:192)
at com.checkpoint.te.shared.BaseLifecycleListener.contextInitialized(BaseLifecycleListener.java:42)
at com.checkpoint.te.shared.TomcatLifecycleListener.contextInitialized(TomcatLifecycleListener.java:13)
at com.checkpoint.te.pod.PodLifecycleListener.contextInitialized(PodLifecycleListener.java:43)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4797)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5291)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:633)
at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:977)
at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1655)
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1121)
at com.mysql.jdbc.MysqlIO.(MysqlIO.java:358)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2489)
at com.mysql.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:2334)
... 48 more
Caused by: java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.(Unknown Source)
at java.net.Socket.(Unknown Source)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:259)
at com.mysql.jdbc.MysqlIO.(MysqlIO.java:308)
... 50 more
[localhost-startStop-1][ ][13 Jan 2016 16:40:48,825] [hbm2ddl.SchemaUpdate ]: [ERROR] HHH000299: Could not complete schema update
com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.Util.getInstance(Util.java:386)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1015)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:989)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:975)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:920)
at com.mysql.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:2395)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2316)
at com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:834)
at com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:47)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:416)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:347)
at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:131)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:156)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:145)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPoolManager.initializeAutomaticTestTable(C3P0PooledConnectionPoolManager.java:898)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPoolManager.createPooledConnectionPool(C3P0PooledConnectionPoolManager.java:821)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPoolManager.getPool(C3P0PooledConnectionPoolManager.java:331)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPoolManager.getPool(C3P0PooledConnectionPoolManager.java:348)
at com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource.getConnection(AbstractPoolBackedDataSource.java:140)
at org.hibernate.c3p0.internal.C3P0ConnectionProvider.getConnection(C3P0ConnectionProvider.java:89)
at org.hibernate.tool.hbm2ddl.SuppliedConnectionProviderConnectionHelper.prepare(SuppliedConnectionProviderConnectionHelper.java:51)
at org.hibernate.tool.hbm2ddl.SchemaUpdate.execute(SchemaUpdate.java:194)
at org.hibernate.tool.hbm2ddl.SchemaUpdate.execute(SchemaUpdate.java:178)
at org.hibernate.internal.SessionFactoryImpl.(SessionFactoryImpl.java:522)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1857)
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:850)
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:843)
at org.hibernate.boot.registry.classloading.internal.ClassLoaderServiceImpl.withTccl(ClassLoaderServiceImpl.java:398)
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:842)
at org.hibernate.jpa.HibernatePersistenceProvider.createEntityManagerFactory(HibernatePersistenceProvider.java:75)
at com.checkpoint.te.shared.service.CustomHibernatePersistence.createEntityManagerFactory(CustomHibernatePersistence.java:43)
at com.checkpoint.te.shared.service.CustomHibernatePersistence.createEntityManagerFactory(CustomHibernatePersistence.java:28)
at com.checkpoint.te.shared.sql.DbHandler.lifeCycleUp(DbHandler.java:192)
at com.checkpoint.te.shared.BaseLifecycleListener.contextInitialized(BaseLifecycleListener.java:42)
at com.checkpoint.te.shared.TomcatLifecycleListener.contextInitialized(TomcatLifecycleListener.java:13)
at com.checkpoint.te.pod.PodLifecycleListener.contextInitialized(PodLifecycleListener.java:43)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4797)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5291)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:633)
at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:977)
at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1655)
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1121)
at com.mysql.jdbc.MysqlIO.(MysqlIO.java:358)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2489)
at com.mysql.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:2334)
... 48 more
Caused by: java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.(Unknown Source)
at java.net.Socket.(Unknown Source)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:259)
at com.mysql.jdbc.MysqlIO.(MysqlIO.java:308)
... 50 more
Can anyone help?
I tried changing the port but nothing helper. Have no idea where to start

This screams "Network issue".
Check the following items:
destination host can be reached on TCP 3306 (run telnet destination 3306 or similar)
check netstat -na while that connection is trying to establish: Any SYN_SENT would indicate a firewall is in the way.
check netstat -na on your MySQL box - is 3306 bound to outside interface (or to 127.0.0.1 / localhost only?)

org.hibernate.exception.JDBCConnectionException: could not execute query using hibernate

I've developed an application and it worked just fine locally , and when I uploaded it to a remote server it gave me com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException. I've tried the solution mentioned in the topic in this link :
https://stackoverflow.com/questions/7565143/com-mysql-jdbc-exceptions-jdbc4-mysqlnontransientconnectionexception-no-operati#=
here is the code that has access to database:
protected Number getCount(Class clazz){
Session currentSession = HibernateUtil.getSessionFactory().getCurrentSession();
Transaction transaction = currentSession.beginTransaction();
return (Number) currentSession.createCriteria(clazz).setProjection(Projections.rowCount()).uniqueResult();
}
and here is my hibernate configuration:
<hibernate-configuration>
<session-factory>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.current_session_context_class">thread</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/lyrics_db</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password">123456</property>
<property name="hibernate.hbm2ddl.auto">update</property>
<property name="hibernate.show_sql">true</property>
<property name="connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>
<property name="c3p0.acquire_increment">1</property>
<property name="c3p0.idle_test_period">100</property>
<!-- seconds -->
<property name="c3p0.max_size">100</property>
<property name="c3p0.max_statements">0</property>
<property name="c3p0.min_size">10</property>
<property name="c3p0.timeout">1800</property>
<!-- seconds -->
</session-factory>
</hibernate-configuration>
and it's not working and I'm getting the same exception , and here is my full stack trace:
Dec 3, 2013 8:02:44 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet ServletAdaptor threw exception
org.hibernate.exception.JDBCConnectionException: could not execute query
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:74)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
at org.hibernate.loader.Loader.doList(Loader.java:2223)
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2104)
at org.hibernate.loader.Loader.list(Loader.java:2099)
at org.hibernate.loader.criteria.CriteriaLoader.list(CriteriaLoader.java:94)
at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1569)
at org.hibernate.impl.CriteriaImpl.list(CriteriaImpl.java:283)
at daos.UltimateDao.listWithLimitWithOrder(UltimateDao.java:47)
at daos.LyricDao.getTopHundred(LyricDao.java:73)
at com.xeeapps.service.Service.getTopHundred(Service.java:91)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.sun.jersey.spi.container.JavaMethodInvokerFactory$1.invoke(JavaMethodInvokerFactory.java:60)
at com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$TypeOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:185)
at com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:75)
at com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:302)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147)
at com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:108)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147)
at com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:84)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1480)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1411)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1360)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1350)
at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:416)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:538)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:716)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:602)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Thread.java:662)
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed.
at sun.reflect.GeneratedConstructorAccessor127.newInstance(Unknown Source)
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:411)
at com.mysql.jdbc.Util.getInstance(Util.java:386)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1014)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:988)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:974)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:919)
at com.mysql.jdbc.ConnectionImpl.throwConnectionClosedException(ConnectionImpl.java:1290)
at com.mysql.jdbc.ConnectionImpl.checkClosed(ConnectionImpl.java:1282)
at com.mysql.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:4468)
at com.mysql.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:4434)
at com.mchange.v2.c3p0.impl.NewProxyConnection.prepareStatement(NewProxyConnection.java:1076)
at org.hibernate.jdbc.AbstractBatcher.getPreparedStatement(AbstractBatcher.java:505)
at org.hibernate.jdbc.AbstractBatcher.getPreparedStatement(AbstractBatcher.java:423)
at org.hibernate.jdbc.AbstractBatcher.prepareQueryStatement(AbstractBatcher.java:139)
at org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:1547)
at org.hibernate.loader.Loader.doQuery(Loader.java:673)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:236)
at org.hibernate.loader.Loader.doList(Loader.java:2220)
... 40 more
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The last packet successfully received from the server was 38,056,253 milliseconds ago. The last packet sent successfully to the server was 38,056,857 milliseconds ago. is longer than the server configured value of 'wait_timeout'. You should consider either expiring and/or testing connection validity before use in your application, increasing the server configured values for client timeouts, or using the Connector/J connection property 'autoReconnect=true' to avoid this problem.
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:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1117)
at com.mysql.jdbc.MysqlIO.send(MysqlIO.java:3871)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2484)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2664)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2794)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2155)
at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2322)
at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeQuery(NewProxyPreparedStatement.java:144)
at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:186)
at org.hibernate.loader.Loader.getResultSet(Loader.java:1787)
at org.hibernate.loader.Loader.doQuery(Loader.java:674)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:236)
at org.hibernate.loader.Loader.doList(Loader.java:2220)
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2104)
at org.hibernate.loader.Loader.list(Loader.java:2099)
at org.hibernate.loader.criteria.CriteriaLoader.list(CriteriaLoader.java:94)
at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1569)
at org.hibernate.impl.CriteriaImpl.list(CriteriaImpl.java:283)
at org.hibernate.impl.CriteriaImpl.uniqueResult(CriteriaImpl.java:305)
at daos.UltimateDao.get(UltimateDao.java:24)
at daos.SongDao.getSong(SongDao.java:31)
at daos.LyricDao.getLyricForSong(LyricDao.java:24)
at com.xeeapps.service.Service.getLyricForASong(Service.java:82)
... 32 more
Caused by: java.net.SocketException: Broken pipe
at java.net.SocketOutputStream.socketWrite0(Native Method)
at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:92)
at java.net.SocketOutputStream.write(SocketOutputStream.java:136)
at java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:65)
at java.io.BufferedOutputStream.flush(BufferedOutputStream.java:123)
at com.mysql.jdbc.MysqlIO.send(MysqlIO.java:3852)
... 53 more
Dec 3, 2013 8:02:44 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet Faces Servlet threw exception
com.sun.jersey.api.client.UniformInterfaceException: GET http://localhost:8080/LyricsService/webresources/service/getTopHundred returned a response status of 500 Internal Server Error
at com.sun.jersey.api.client.WebResource.handle(WebResource.java:686)
at com.sun.jersey.api.client.WebResource.access$200(WebResource.java:74)
at com.sun.jersey.api.client.WebResource$Builder.get(WebResource.java:507)
at client.LyricsClient.getTopHundred(LyricsClient.java:71)
at controllers.TopHundredController.init(TopHundredController.java:32)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.el.parser.AstValue.invoke(AstValue.java:191)
at org.apache.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:276)
at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:105)
at com.sun.faces.facelets.tag.jsf.core.DeclarativeSystemEventListener.processEvent(EventHandler.java:128)
at javax.faces.component.UIComponent$ComponentSystemEventListenerAdapter.processEvent(UIComponent.java:2563)
at javax.faces.event.SystemEvent.processListener(SystemEvent.java:108)
at javax.faces.event.ComponentSystemEvent.processListener(ComponentSystemEvent.java:118)
at com.sun.faces.application.ApplicationImpl.processListeners(ApplicationImpl.java:2187)
at com.sun.faces.application.ApplicationImpl.invokeComponentListenersFor(ApplicationImpl.java:2135)
at com.sun.faces.application.ApplicationImpl.publishEvent(ApplicationImpl.java:289)
at com.sun.faces.application.ApplicationImpl.publishEvent(ApplicationImpl.java:247)
at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:107)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:219)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:647)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:602)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Thread.java:662)
Does anyone know why this exception keeps happening even I changed my configuration?

I guess the problem was that I didn't commit the transaction , so it made some sort of lock.I figured this out from this topic:
What happens if you don't commit transaction in a database (say SQL Server)

hibernate to MSSQL server Connection refused: connect

Im trying to run a java desktop application which accesses a MSSQL server using hibernate, but when trying to connect, it throws an exception and i really dont know what to do, here is my config 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">
<!-- Generated by MyEclipse Hibernate Tools. -->
<hibernate-configuration>
<session-factory>
<property name="connection.username"></property>
<property name="connection.password"></property>
<property name="connection.url">
jdbc:jtds:sqlserver://localhost/databasename;useNTLMv2=true
</property>
<property name="dialect">
ba.fit.utilities.FDialect_SqlServer
</property>
<property name="myeclipse.connection.profile">nova 3</property>
<property name="connection.driver_class">
net.sourceforge.jtds.jdbc.Driver
</property>
<!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size">1</property>
<!-- Opcije printanja SQL koda u konzolnom prozoru-->
<property name="show_sql">true</property>
<property name="format_sql">false</property>
<property name="use_sql_comments">false</property>
<!--vrijednost "update" kreira tabele ako nepostoje, ali ih nece mijenjati ako ima potrebe-->
<property name="hibernate.hbm2ddl.auto">update</property>
<!-- Enable Hibernate's automatic session context management -->
<property name="current_session_context_class">thread</property>
<!-- Disable the second-level cache -->
<property name="cache.provider_class">
org.hibernate.cache.NoCacheProvider
</property>
<!-- mapirane klase koje trebaju biti "persistence" -->
<!--
-->
<mapping class="ba.fit.Tomo_seminar.model.Administrator" />
<mapping class="ba.fit.Tomo_seminar.model.BiografijaPosloprimca" />
<mapping class="ba.fit.Tomo_seminar.model.BiografijaPoslodavca" />
<mapping class="ba.fit.Tomo_seminar.model.Drzava" />
<mapping class="ba.fit.Tomo_seminar.model.Grad" />
<mapping class="ba.fit.Tomo_seminar.model.Kategorija" />
<mapping class="ba.fit.Tomo_seminar.model.KategorijaBiografija" />
<mapping class="ba.fit.Tomo_seminar.model.OcjenePoslodavca" />
<mapping class="ba.fit.Tomo_seminar.model.OcjenePosloprimca" />
<mapping class="ba.fit.Tomo_seminar.model.Poslodavac" />
<mapping class="ba.fit.Tomo_seminar.model.Posloprimaoc" />
<mapping class="ba.fit.Tomo_seminar.model.Projekt" />
<mapping class="ba.fit.Tomo_seminar.model.ProjektKategorija" />
<mapping class="ba.fit.Tomo_seminar.model.Racun" />
<mapping class="ba.fit.Tomo_seminar.model.StatusTuzbe" />
<mapping class="ba.fit.Tomo_seminar.model.StrucnaSprema" />
<mapping class="ba.fit.Tomo_seminar.model.Tuzba" />
<mapping class="ba.fit.Tomo_seminar.model.Uplatnica" />
<mapping class="ba.fit.Tomo_seminar.model.ZahtjevZaRadNaProjektu" />
<mapping class="ba.fit.Tomo_seminar.model.RadnoVrijeme" />
</session-factory>
</hibernate-configuration>
but i get this exception
20:52:43,562 WARN SettingsFactory:109 - Could not obtain connection metadata
java.sql.SQLException: Network error IOException: Connection refused: connect
at net.sourceforge.jtds.jdbc.ConnectionJDBC2.<init>(ConnectionJDBC2.java:410)
at net.sourceforge.jtds.jdbc.ConnectionJDBC3.<init>(ConnectionJDBC3.java:50)
at net.sourceforge.jtds.jdbc.Driver.connect(Driver.java:184)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at org.hibernate.connection.DriverManagerConnectionProvider.getConnection(DriverManagerConnectionProvider.java:110)
at org.hibernate.cfg.SettingsFactory.buildSettings(SettingsFactory.java:76)
at org.hibernate.cfg.Configuration.buildSettings(Configuration.java:1933)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1216)
at org.hibernate.cfg.AnnotationConfiguration.buildSessionFactory(AnnotationConfiguration.java:915)
at ba.fit.utilities.HibernateUtil.<clinit>(HibernateUtil.java:24)
at ba.fit.Tomo_seminar.persistence.PosloprimaocDAO.pronadji(PosloprimaocDAO.java:17)
at ba.fit.Tomo_seminar.services.servLogin.LoginPosloprimaoc(servLogin.java:31)
at ba.fit.imeprojekta.ui.gui.v1.FrmLogin.do_btnLogin_widgetSelected(FrmLogin.java:142)
at ba.fit.imeprojekta.ui.gui.v1.FrmLogin$1.widgetSelected(FrmLogin.java:92)
at org.eclipse.swt.widgets.TypedListener.handleEvent(Unknown Source)
at org.eclipse.swt.widgets.EventTable.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Widget.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Unknown Source)
at org.eclipse.swt.widgets.Display.readAndDispatch(Unknown Source)
at ba.fit.imeprojekta.ui.gui.v1.FrmLogin.main(FrmLogin.java:44)
Caused by: java.net.ConnectException: Connection refused: connect
at java.net.TwoStacksPlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at net.sourceforge.jtds.jdbc.SharedSocket.createSocketForJDBC3(SharedSocket.java:307)
at net.sourceforge.jtds.jdbc.SharedSocket.<init>(SharedSocket.java:257)
at net.sourceforge.jtds.jdbc.ConnectionJDBC2.<init>(ConnectionJDBC2.java:311)
... 20 more
20:52:46,015 ERROR SchemaUpdate:134 - could not get database metadata
java.sql.SQLException: Network error IOException: Connection refused: connect
at net.sourceforge.jtds.jdbc.ConnectionJDBC2.<init>(ConnectionJDBC2.java:410)
at net.sourceforge.jtds.jdbc.ConnectionJDBC3.<init>(ConnectionJDBC3.java:50)
at net.sourceforge.jtds.jdbc.Driver.connect(Driver.java:184)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at org.hibernate.connection.DriverManagerConnectionProvider.getConnection(DriverManagerConnectionProvider.java:110)
at org.hibernate.tool.hbm2ddl.SuppliedConnectionProviderConnectionHelper.prepare(SuppliedConnectionProviderConnectionHelper.java:27)
at org.hibernate.tool.hbm2ddl.SchemaUpdate.execute(SchemaUpdate.java:127)
at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:314)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1218)
at org.hibernate.cfg.AnnotationConfiguration.buildSessionFactory(AnnotationConfiguration.java:915)
at ba.fit.utilities.HibernateUtil.<clinit>(HibernateUtil.java:24)
at ba.fit.Tomo_seminar.persistence.PosloprimaocDAO.pronadji(PosloprimaocDAO.java:17)
at ba.fit.Tomo_seminar.services.servLogin.LoginPosloprimaoc(servLogin.java:31)
at ba.fit.imeprojekta.ui.gui.v1.FrmLogin.do_btnLogin_widgetSelected(FrmLogin.java:142)
at ba.fit.imeprojekta.ui.gui.v1.FrmLogin$1.widgetSelected(FrmLogin.java:92)
at org.eclipse.swt.widgets.TypedListener.handleEvent(Unknown Source)
at org.eclipse.swt.widgets.EventTable.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Widget.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Unknown Source)
at org.eclipse.swt.widgets.Display.readAndDispatch(Unknown Source)
at ba.fit.imeprojekta.ui.gui.v1.FrmLogin.main(FrmLogin.java:44)
Caused by: java.net.ConnectException: Connection refused: connect
at java.net.TwoStacksPlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at net.sourceforge.jtds.jdbc.SharedSocket.createSocketForJDBC3(SharedSocket.java:307)
at net.sourceforge.jtds.jdbc.SharedSocket.<init>(SharedSocket.java:257)
at net.sourceforge.jtds.jdbc.ConnectionJDBC2.<init>(ConnectionJDBC2.java:311)
... 21 more
20:52:46,015 ERROR SchemaUpdate:165 - could not complete schema update
java.sql.SQLException: Network error IOException: Connection refused: connect
at net.sourceforge.jtds.jdbc.ConnectionJDBC2.<init>(ConnectionJDBC2.java:410)
at net.sourceforge.jtds.jdbc.ConnectionJDBC3.<init>(ConnectionJDBC3.java:50)
at net.sourceforge.jtds.jdbc.Driver.connect(Driver.java:184)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at org.hibernate.connection.DriverManagerConnectionProvider.getConnection(DriverManagerConnectionProvider.java:110)
at org.hibernate.tool.hbm2ddl.SuppliedConnectionProviderConnectionHelper.prepare(SuppliedConnectionProviderConnectionHelper.java:27)
at org.hibernate.tool.hbm2ddl.SchemaUpdate.execute(SchemaUpdate.java:127)
at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:314)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1218)
at org.hibernate.cfg.AnnotationConfiguration.buildSessionFactory(AnnotationConfiguration.java:915)
at ba.fit.utilities.HibernateUtil.<clinit>(HibernateUtil.java:24)
at ba.fit.Tomo_seminar.persistence.PosloprimaocDAO.pronadji(PosloprimaocDAO.java:17)
at ba.fit.Tomo_seminar.services.servLogin.LoginPosloprimaoc(servLogin.java:31)
at ba.fit.imeprojekta.ui.gui.v1.FrmLogin.do_btnLogin_widgetSelected(FrmLogin.java:142)
at ba.fit.imeprojekta.ui.gui.v1.FrmLogin$1.widgetSelected(FrmLogin.java:92)
at org.eclipse.swt.widgets.TypedListener.handleEvent(Unknown Source)
at org.eclipse.swt.widgets.EventTable.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Widget.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Unknown Source)
at org.eclipse.swt.widgets.Display.readAndDispatch(Unknown Source)
at ba.fit.imeprojekta.ui.gui.v1.FrmLogin.main(FrmLogin.java:44)
Caused by: java.net.ConnectException: Connection refused: connect
at java.net.TwoStacksPlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at net.sourceforge.jtds.jdbc.SharedSocket.createSocketForJDBC3(SharedSocket.java:307)
at net.sourceforge.jtds.jdbc.SharedSocket.<init>(SharedSocket.java:257)
at net.sourceforge.jtds.jdbc.ConnectionJDBC2.<init>(ConnectionJDBC2.java:311)
... 21 more
20:52:47,328 WARN JDBCExceptionReporter:71 - SQL Error: 0, SQLState: 08S01
20:52:47,328 ERROR JDBCExceptionReporter:72 - Network error IOException: Connection refused: connect

Seems connection.url has an issue. Correct url would be
<property name="hibernate.connection.driver_class">com.microsoft.sqlserver.jdbc.SQLServerDriver</property>
<property name="hibernate.connection.url">jdbc:sqlserver://machine:1433;databaseName=databaseName;</property>

Socket is being closed on server before postgres returns result - c3p0

This only happens when the system is under load. At least it is noticable then.
Postgres 8.3.14
JDK 1.6
Tomcat 6
Machine has 7GB of memory
I've noticed my postgres data directory is eating up my entire hd as well. I have postgres on a 100GB drive and it will fill it up within a few hours.
I have 10 million rows, lots of joins, mostly reads.
I'm noticing this now because my usage has increased 10x overnight.
shared_buffers = 2GB
effective_cache_size = 3GB
everything else if pretty much left unchanged
21:56:59,736 DEBUG BasicResourcePool:1620 - trace com.mchange.v2.resourcepool.BasicResourcePool#176b9ea [managed: 24, unused: 1, excluded: 0] (e.g. com.mchange.v2.c3p0.impl.NewPooledConnection#1c3dc66)
21:56:59,736 DEBUG BasicResourcePool:1620 - trace com.mchange.v2.resourcepool.BasicResourcePool#176b9ea [managed: 24, unused: 1, excluded: 0] (e.g. com.mchange.v2.c3p0.impl.NewPooledConnection#1c3dc66)
21:56:59,736 DEBUG BasicResourcePool:1450 - FINISHED check for expired resources. [com.mchange.v2.resourcepool.BasicResourcePool#176b9ea]
21:56:59,736 DEBUG BasicResourcePool:956 - Preparing to destroy resource: com.mchange.v2.c3p0.impl.NewPooledConnection#1e0a562
21:56:59,736 DEBUG C3P0PooledConnectionPool:468 - Preparing to destroy PooledConnection: com.mchange.v2.c3p0.impl.NewPooledConnection#1e0a562
21:56:59,736 DEBUG NewPooledConnection:564 - com.mchange.v2.c3p0.impl.NewPooledConnection#1e0a562 closed by a client.
java.lang.Exception: DEBUG -- CLOSE BY CLIENT STACK TRACE
at com.mchange.v2.c3p0.impl.NewPooledConnection.close(NewPooledConnection.java:564)
at com.mchange.v2.c3p0.impl.NewPooledConnection.close(NewPooledConnection.java:234)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.destroyResource(C3P0PooledConnectionPool.java:470)
at com.mchange.v2.resourcepool.BasicResourcePool$1DestroyResourceTask.run(BasicResourcePool.java:958)
at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
21:56:59,736 DEBUG C3P0PooledConnectionPool:476 - Successfully destroyed PooledConnection: com.mchange.v2.c3p0.impl.NewPooledConnection#1e0a562
21:56:59,736 DEBUG BasicResourcePool:961 - Successfully destroyed resource: com.mchange.v2.c3p0.impl.NewPooledConnection#1e0a562
21:56:59,737 DEBUG NewPooledConnection:430 - com.mchange.v2.c3p0.impl.NewPooledConnection#1e0a562 handling a throwable.
org.postgresql.util.PSQLException: An I/O error occured while sending to the backend.
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:283)
at org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:479)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.java:367)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeQuery(AbstractJdbc2Statement.java:271)
at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeQuery(NewProxyPreparedStatement.java:76)
at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:208)
at org.hibernate.loader.Loader.getResultSet(Loader.java:1953)
at org.hibernate.loader.Loader.doQuery(Loader.java:802)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:274)
at org.hibernate.loader.Loader.loadEntity(Loader.java:2037)
at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:86)
at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:76)
at org.hibernate.persister.entity.AbstractEntityPersister.load(AbstractEntityPersister.java:3268)
at org.hibernate.event.def.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:496)
at org.hibernate.event.def.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:477)
at org.hibernate.event.def.DefaultLoadEventListener.load(DefaultLoadEventListener.java:227)
at org.hibernate.event.def.DefaultLoadEventListener.lockAndLoad(DefaultLoadEventListener.java:403)
at org.hibernate.event.def.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:155)
at org.hibernate.impl.SessionImpl.fireLoad(SessionImpl.java:1090)
at org.hibernate.impl.SessionImpl.load(SessionImpl.java:1061)
at org.hibernate.impl.SessionImpl.load(SessionImpl.java:1050)
at com.icon.sa.common.dm.dao.BaseDao.findByIdLockedOrException(BaseDao.java:52)
at com.icon.sa.service.action.auser.ItemUpdateAction.pre(ItemUpdateAction.java:28)
at com.icon.sa.service.action.BaseAction.perform(BaseAction.java:59)
at com.icon.sa.ws.auser.ItemResource.update(ItemResource.java:43)
at sun.reflect.GeneratedMethodAccessor299.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:616)
at com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$TypeOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:168)
at com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:70)
at com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:279)
at com.sun.jersey.server.impl.uri.rules.SubLocatorRule.accept(SubLocatorRule.java:121)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:136)
at com.sun.jersey.server.impl.uri.rules.SubLocatorRule.accept(SubLocatorRule.java:121)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:136)
at com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:86)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:136)
at com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:74)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1357)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1289)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1239)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1229)
at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:420)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:497)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:684)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.valves.RemoteIpValve.invoke(RemoteIpValve.java:647)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:864)
at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:579)
at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1665)
at java.lang.Thread.run(Thread.java:636)
Caused by: java.net.SocketException: Socket closed
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:146)
at org.postgresql.core.VisibleBufferedInputStream.readMore(VisibleBufferedInputStream.java:135)
at org.postgresql.core.VisibleBufferedInputStream.ensureBytes(VisibleBufferedInputStream.java:104)
at org.postgresql.core.VisibleBufferedInputStream.read(VisibleBufferedInputStream.java:73)
at org.postgresql.core.PGStream.ReceiveChar(PGStream.java:259)
at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1620)
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:257)
... 58 more
21:56:59,737 DEBUG SqlUtils:85 - Attempted to convert SQLException to SQLException. Leaving it alone. [SQLState: 08006; errorCode: 0]
org.postgresql.util.PSQLException: An I/O error occured while sending to the backend.
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:283)
at org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:479)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.java:367)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeQuery(AbstractJdbc2Statement.java:271)
at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeQuery(NewProxyPreparedStatement.java:76)
at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:208)
at org.hibernate.loader.Loader.getResultSet(Loader.java:1953)
at org.hibernate.loader.Loader.doQuery(Loader.java:802)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:274)
at org.hibernate.loader.Loader.loadEntity(Loader.java:2037)
at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:86)
at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:76)
at org.hibernate.persister.entity.AbstractEntityPersister.load(AbstractEntityPersister.java:3268)
at org.hibernate.event.def.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:496)
at org.hibernate.event.def.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:477)
at org.hibernate.event.def.DefaultLoadEventListener.load(DefaultLoadEventListener.java:227)
at org.hibernate.event.def.DefaultLoadEventListener.lockAndLoad(DefaultLoadEventListener.java:403)
at org.hibernate.event.def.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:155)
at org.hibernate.impl.SessionImpl.fireLoad(SessionImpl.java:1090)
at org.hibernate.impl.SessionImpl.load(SessionImpl.java:1061)
at org.hibernate.impl.SessionImpl.load(SessionImpl.java:1050)
at com.icon.sa.common.dm.dao.BaseDao.findByIdLockedOrException(BaseDao.java:52)
at com.icon.sa.service.action.auser.ItemUpdateAction.pre(ItemUpdateAction.java:28)
at com.icon.sa.service.action.BaseAction.perform(BaseAction.java:59)
at com.icon.sa.ws.auser.ItemResource.update(ItemResource.java:43)
at sun.reflect.GeneratedMethodAccessor299.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:616)
at com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$TypeOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:168)
at com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:70)
at com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:279)
at com.sun.jersey.server.impl.uri.rules.SubLocatorRule.accept(SubLocatorRule.java:121)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:136)
at com.sun.jersey.server.impl.uri.rules.SubLocatorRule.accept(SubLocatorRule.java:121)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:136)
at com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:86)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:136)
at com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:74)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1357)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1289)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1239)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1229)
at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:420)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:497)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:684)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.valves.RemoteIpValve.invoke(RemoteIpValve.java:647)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:864)
at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:579)
at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1665)
at java.lang.Thread.run(Thread.java:636)
Caused by: java.net.SocketException: Socket closed
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:146)
at org.postgresql.core.VisibleBufferedInputStream.readMore(VisibleBufferedInputStream.java:135)
at org.postgresql.core.VisibleBufferedInputStream.ensureBytes(VisibleBufferedInputStream.java:104)
at org.postgresql.core.VisibleBufferedInputStream.read(VisibleBufferedInputStream.java:73)
at org.postgresql.core.PGStream.ReceiveChar(PGStream.java:259)
at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1620)
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:257)
... 58 more
21:56:59,738 DEBUG DefaultConnectionTester:126 - Testing a Connection in response to an Exception:
org.postgresql.util.PSQLException: An I/O error occured while sending to the backend.
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:283)
at org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:479)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.java:367)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeQuery(AbstractJdbc2Statement.java:271)
at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeQuery(NewProxyPreparedStatement.java:76)
at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:208)
at org.hibernate.loader.Loader.getResultSet(Loader.java:1953)
at org.hibernate.loader.Loader.doQuery(Loader.java:802)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:274)
at org.hibernate.loader.Loader.loadEntity(Loader.java:2037)
at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:86)
at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:76)
at org.hibernate.persister.entity.AbstractEntityPersister.load(AbstractEntityPersister.java:3268)
at org.hibernate.event.def.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:496)
at org.hibernate.event.def.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:477)
at org.hibernate.event.def.DefaultLoadEventListener.load(DefaultLoadEventListener.java:227)
at org.hibernate.event.def.DefaultLoadEventListener.lockAndLoad(DefaultLoadEventListener.java:403)
at org.hibernate.event.def.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:155)
at org.hibernate.impl.SessionImpl.fireLoad(SessionImpl.java:1090)
at org.hibernate.impl.SessionImpl.load(SessionImpl.java:1061)
at org.hibernate.impl.SessionImpl.load(SessionImpl.java:1050)
at com.icon.sa.common.dm.dao.BaseDao.findByIdLockedOrException(BaseDao.java:52)
at com.icon.sa.service.action.auser.ItemUpdateAction.pre(ItemUpdateAction.java:28)
at com.icon.sa.service.action.BaseAction.perform(BaseAction.java:59)
at com.icon.sa.ws.auser.ItemResource.update(ItemResource.java:43)
at sun.reflect.GeneratedMethodAccessor299.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:616)
at com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$TypeOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:168)
at com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:70)
at com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:279)
at com.sun.jersey.server.impl.uri.rules.SubLocatorRule.accept(SubLocatorRule.java:121)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:136)
at com.sun.jersey.server.impl.uri.rules.SubLocatorRule.accept(SubLocatorRule.java:121)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:136)
at com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:86)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:136)
at com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:74)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1357)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1289)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1239)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1229)
at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:420)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:497)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:684)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.valves.RemoteIpValve.invoke(RemoteIpValve.java:647)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:864)
at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:579)
at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1665)
at java.lang.Thread.run(Thread.java:636)
Caused by: java.net.SocketException: Socket closed
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:146)
at org.postgresql.core.VisibleBufferedInputStream.readMore(VisibleBufferedInputStream.java:135)
at org.postgresql.core.VisibleBufferedInputStream.ensureBytes(VisibleBufferedInputStream.java:104)
at org.postgresql.core.VisibleBufferedInputStream.read(VisibleBufferedInputStream.java:73)
at org.postgresql.core.PGStream.ReceiveChar(PGStream.java:259)
at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1620)
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:257)
... 58 more
21:56:59,738 DEBUG DefaultConnectionTester:194 - Connection org.postgresql.jdbc4.Jdbc4Connection#3aca failed default system-table Connection test with an Exception!
org.postgresql.util.PSQLException: An I/O error occured while sending to the backend.
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:283)
at org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:479)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.java:353)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeQuery(AbstractJdbc2Statement.java:252)
at org.postgresql.jdbc2.AbstractJdbc2DatabaseMetaData.getTables(AbstractJdbc2DatabaseMetaData.java:2062)
at com.mchange.v2.c3p0.impl.DefaultConnectionTester.activeCheckConnectionNoQuery(DefaultConnectionTester.java:185)
at com.mchange.v2.c3p0.impl.DefaultConnectionTester.activeCheckConnection(DefaultConnectionTester.java:62)
at com.mchange.v2.c3p0.impl.DefaultConnectionTester.statusOnException(DefaultConnectionTester.java:143)
at com.mchange.v2.c3p0.AbstractConnectionTester.statusOnException(AbstractConnectionTester.java:82)
at com.mchange.v2.c3p0.impl.NewPooledConnection.handleThrowable(NewPooledConnection.java:437)
at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeQuery(NewProxyPreparedStatement.java:93)
at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:208)
at org.hibernate.loader.Loader.getResultSet(Loader.java:1953)
at org.hibernate.loader.Loader.doQuery(Loader.java:802)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:274)
at org.hibernate.loader.Loader.loadEntity(Loader.java:2037)
at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:86)
at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:76)
at org.hibernate.persister.entity.AbstractEntityPersister.load(AbstractEntityPersister.java:3268)
at org.hibernate.event.def.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:496)
at org.hibernate.event.def.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:477)
at org.hibernate.event.def.DefaultLoadEventListener.load(DefaultLoadEventListener.java:227)
at org.hibernate.event.def.DefaultLoadEventListener.lockAndLoad(DefaultLoadEventListener.java:403)
at org.hibernate.event.def.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:155)
at org.hibernate.impl.SessionImpl.fireLoad(SessionImpl.java:1090)
at org.hibernate.impl.SessionImpl.load(SessionImpl.java:1061)
at org.hibernate.impl.SessionImpl.load(SessionImpl.java:1050)
at com.icon.sa.common.dm.dao.BaseDao.findByIdLockedOrException(BaseDao.java:52)
at com.icon.sa.service.action.auser.ItemUpdateAction.pre(ItemUpdateAction.java:28)
at com.icon.sa.service.action.BaseAction.perform(BaseAction.java:59)
at com.icon.sa.ws.auser.ItemResource.update(ItemResource.java:43)
at sun.reflect.GeneratedMethodAccessor299.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:616)
at com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$TypeOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:168)
at com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:70)
at com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:279)
at com.sun.jersey.server.impl.uri.rules.SubLocatorRule.accept(SubLocatorRule.java:121)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:136)
at com.sun.jersey.server.impl.uri.rules.SubLocatorRule.accept(SubLocatorRule.java:121)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:136)
at com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:86)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:136)
at com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:74)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1357)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1289)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1239)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1229)
at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:420)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:497)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:684)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.valves.RemoteIpValve.invoke(RemoteIpValve.java:647)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:864)
at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:579)
at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1665)
at java.lang.Thread.run(Thread.java:636)
Caused by: java.io.IOException: Stream closed
at sun.nio.cs.StreamEncoder.ensureOpen(StreamEncoder.java:44)
at sun.nio.cs.StreamEncoder.flush(StreamEncoder.java:139)
at java.io.OutputStreamWriter.flush(OutputStreamWriter.java:229)
at org.postgresql.core.PGStream.flush(PGStream.java:507)
at org.postgresql.core.v3.QueryExecutorImpl.sendSync(QueryExecutorImpl.java:1107)
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:256)
... 64 more
Here is my config
<property name="c3p0.acquire_increment">1</property>
<property name="c3p0.idle_test_period">100</property> <!-- seconds -->
<property name="c3p0.max_size">250</property>
<property name="c3p0.max_statements">0</property>
<property name="c3p0.min_size">10</property>
<property name="c3p0.timeout">100</property> <!-- seconds -->
<!-- Configuring Connection Testing -->
<!-- Create a test table to query for on checkout and checkin. A test table
is faster than to use the getTables default cmd. -->
<property name="automaticTestTable">c3p0_test</property>
<property name="checkoutTimeout">0</property>
<!-- This tests to make sure the connection is still valid (needed for high load system). -->
<property name="testConnectionOnCheckout">true</property>
<property name="testConnectionOnCheckin">true</property>
<!-- Configuring Recovery From Database Outages -->
<property name="acquireRetryAttempts">0</property>
<property name="acquireRetryDelay">1000</property>
<property name="breakAfterAcquireFailure">false</property>
<!-- This is a safeguard to cleanup any open, abandoned connections.
These are connections that are opened but never closed. Debug on server if this ever needs
to cleanup.
We can test without this feature (its discouraged to use) -->
<property name="unreturnedConnectionTimeout">300</property>
<property name="debugUnreturnedConnectionStackTraces">true</property>

These sort of things are usually caused by back-end crashes. It is likely there is a bad extension or library that is making a mess of things. What you'd want to do is check the PostgreSQL logs for errors, or capture queries and try to see where this happens. If that doesn't trace the problem it could be failing hardware.
On a database server this sort of thing is relatively urgent in the sense that it may interfere with data being saved or even result in database corruption. My recommendation is to seek professional help as soon as possible if you seen an issue like this.

Hibernate+PostgreSQL throws JDBCConnectionException: Cannot open connection

I write an Test Java APP and it works right BUt this Web app throws an exception like that with to same cfg.xml file
<property name="hibernate.bytecode.use_reflection_optimizer">false</property>
<property name="hibernate.connection.autocommit">true</property>
<property name="hibernate.connection.release_mode">auto</property>
<property name="hibernate.current_session_context_class">thread</property>
<property name="hibernate.connection.driver_class">org.postgresql.Driver</property>
<property name="hibernate.connection.password">1234</property>
<property name="hibernate.connection.url">jdbc:postgresql://localhost/postgres</property>
<property name="hibernate.connection.username">postgres</property>
<property name="hibernate.default_schema">public</property>
<property name="hibernate.dialect">org.hibernate.dialect.PostgreSQLDialect</property>
<property name="hibernate.ejb.discard_pc_on_close">false</property>
<property name="hibernate.query.jpaql_strict_compliance">true</property>
<property name="hibernate.transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory</property>
<property name="hibernate.transaction.flush_before_completion">false</property>
<property name="hibernate.show_sql">false</property>
<property name="hibernate.generate_statistics">false</property>
<property name="hibernate.use_sql_comments">false</property>
<property name="hibernate.connection.pool_size">100</property>
When I press "Save" button I get the following exception:
javax.servlet.ServletException: org.hibernate.exception.JDBCConnectionException: Cannot open connection
javax.faces.webapp.FacesServlet.service(FacesServlet.java:325)
root cause
javax.faces.el.EvaluationException: org.hibernate.exception.JDBCConnectionException: Cannot open connection
javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:102)
com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102)
javax.faces.component.UICommand.broadcast(UICommand.java:315)
javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:775)
javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1267)
com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:82)
com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
javax.faces.webapp.FacesServlet.service(FacesServlet.java:312)
root cause
org.hibernate.exception.JDBCConnectionException: Cannot open connection
org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:98)
org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:52)
org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:449)
org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:167)
org.hibernate.jdbc.JDBCContext.connection(JDBCContext.java:142)
org.hibernate.transaction.JDBCTransaction.begin(JDBCTransaction.java:85)
org.hibernate.impl.SessionImpl.beginTransaction(SessionImpl.java:1463)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.hibernate.context.ThreadLocalSessionContext$TransactionProtectionWrapper.invoke(ThreadLocalSessionContext.java:344)
$Proxy108.beginTransaction(Unknown Source)
com.yemex.beans.CompanyBean.saveOrUpdate(CompanyBean.java:52)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.apache.el.parser.AstValue.invoke(AstValue.java:196)
org.apache.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:276)
com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:98)
javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:88)
com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102)
javax.faces.component.UICommand.broadcast(UICommand.java:315)
javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:775)
javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1267)
com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:82)
com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
javax.faces.webapp.FacesServlet.service(FacesServlet.java:312)
root cause
java.sql.SQLException: No suitable driver found for jdbc:postgresql://localhost/postgres
java.sql.DriverManager.getConnection(Unknown Source)
java.sql.DriverManager.getConnection(Unknown Source)
org.hibernate.connection.DriverManagerConnectionProvider.getConnection(DriverManagerConnectionProvider.java:133)
org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:446)
org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:167)
org.hibernate.jdbc.JDBCContext.connection(JDBCContext.java:142)
org.hibernate.transaction.JDBCTransaction.begin(JDBCTransaction.java:85)
org.hibernate.impl.SessionImpl.beginTransaction(SessionImpl.java:1463)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.hibernate.context.ThreadLocalSessionContext$TransactionProtectionWrapper.invoke(ThreadLocalSessionContext.java:344)
$Proxy108.beginTransaction(Unknown Source)
com.yemex.beans.CompanyBean.saveOrUpdate(CompanyBean.java:52)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.apache.el.parser.AstValue.invoke(AstValue.java:196)
org.apache.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:276)
com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:98)
javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:88)
com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102)
javax.faces.component.UICommand.broadcast(UICommand.java:315)
javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:775)
javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1267)
com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:82)
com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
javax.faces.webapp.FacesServlet.service(FacesServlet.java:312)
Blockquote

When encountering an exception, it's worth to check the bottommost root cause in the stacktrace. In this case it's the following:
java.sql.SQLException: No suitable driver found for jdbc:postgresql://localhost/postgres
This just means that either the URL is wrong or that the desired driver is not present in the current runtime classpath. Since the URL looks fine as per the PostgreSQL JDBC documentation, it'll be that the driver is missing in the current runtime classpath.
So, to fix this problem, you need put the JDBC driver JAR file in the webapp's runtime classpath. The /WEB-INF/lib is one of the folders which is covered by the webapp's default runtime classpath. Just drop the PostgreSQL JDBC driver JAR file in there and redeploy.

What's the question here?
The exception is pretty explicit:
org.hibernate.exception.JDBCConnectionException: Cannot open connection
Make sure you can connect to the database you are connected to, that the configuration is correct, that you do not have network issues preventing the connection, etc.

I didn't look at your config file, but I'm assuming it configured at least reasonably well since the stack trace indicates that it is trying to connect to a postgres database at a localhost JDBC url.
It looks like the big problem is that it can't find the postgres JDBC driver:
root cause
java.sql.SQLException: No suitable driver found for jdbc:postgresql://localhost/postgres java.sql.DriverManager.getConnection(Unknown Source) java.sql.DriverManager.getConnection(Unknown Source) org.hibernate.connection.DriverManagerConnectionProvider.getConnection(DriverManagerConnectionProvider.java:133)
Make sure the JAR file is in your classpath. You can download it here, if you don't already have it:
http://jdbc.postgresql.org/

Verify that you have the jar for your database driver in classpath.
Verify if the driver class name is correct.
Verify if the connection.url is correct.
I got the same error. Only difference being, I am using Oracle 11g. I had ojdbc14.jar in classpath , driver class name was correct but connection.url property was wrong.
The correct format in case of Oracle 11g is
jdbc:oracle:thin:#localhost:1521:global_dsn_name