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Sql Server The connection is closed

I have a java spring app connected to a database under SQL Server 2012.
THis is the properties and the datasource i am using :
-datasource.initialSize=34
-datasource.minIdle=89
-datasource.maxIdle=233
-datasource.maxActive=377
-datasource.maxWait=50000
-datasource.abandonWhenPercentageFull=50
-datasource.jmxEnabled=true
-datasource.removeAbandoned=true
-datasource.removeAbandonedTimeout=120
-datasource.logAbandoned=true
-datasource.testOnBorrow=true
-datasource.timeBetweenEvictionRunsMillis=60000
-datasource.minEvictableIdleTimeMillis=80000
-datasource.validationInterval=40000
and the datasource managed by spring :
<bean id="myDataSource" class="org.apache.tomcat.jdbc.pool.DataSource" destroy-method="close"
p:driverClassName="${datasource.driverClass}"
p:url="${datasource.url}"
p:username="${datasource.user}"
p:password="${datasource.pass}"
p:maxWait="${datasource.maxWait}"
p:minIdle="${datasource.minIdle}"
p:maxIdle="${datasource.maxIdle}"
p:maxActive="${datasource.maxActive}"
p:jmxEnabled="${datasource.jmxEnabled}"
p:removeAbandoned="${datasource.removeAbandoned}"
p:removeAbandonedTimeout="${datasource.removeAbandonedTimeout}"
p:logAbandoned="${datasource.logAbandoned}"
p:testOnBorrow="${datasource.testOnBorrow}"
p:timeBetweenEvictionRunsMillis="${datasource.timeBetweenEvictionRunsMillis}"
p:minEvictableIdleTimeMillis="${datasource.minEvictableIdleTimeMillis}"
p:validationInterval="${datasource.validationInterval}"
p:abandonWhenPercentageFull="${datasource.abandonWhenPercentageFull}"
p:validationQuery="SELECT 1"
p:jdbcInterceptors="org.apache.tomcat.jdbc.pool.interceptor.ResetAbandonedTimer;org.apache.tomcat.jdbc.pool.interceptor.StatementFinalizer;org.apache.tomcat.jdbc.pool.interceptor.ConnectionState"
/>
I have got a process which send a lot JMS Messages. I get the same error message at various time saying that the The Connection is Closed in my JMS Listenner. Any idea why it closes the connection ?
org.springframework.transaction.TransactionSystemException: Could not commit Hibernate transaction; nested exception is org.hibernate.TransactionException: Unable to commit against JDBC Connection
at org.springframework.orm.hibernate5.HibernateTransactionManager.doCommit(HibernateTransactionManager.java:585)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:761)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:730)
at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:485)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:291)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at com.spectrags.fundhive.interceptor.PerfInterceptor.invoke(PerfInterceptor.java:34)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:653)
at com.spectrags.fundhive.business.api.messaging.WorkflowJmsListener$$EnhancerBySpringCGLIB$$704b2c20.onMessage(<generated>)
at org.springframework.jms.listener.AbstractMessageListenerContainer.doInvokeListener(AbstractMessageListenerContainer.java:746)
at org.springframework.jms.listener.AbstractMessageListenerContainer.invokeListener(AbstractMessageListenerContainer.java:684)
at org.springframework.jms.listener.AbstractMessageListenerContainer.doExecuteListener(AbstractMessageListenerContainer.java:651)
at org.springframework.jms.listener.AbstractPollingMessageListenerContainer.doReceiveAndExecute(AbstractPollingMessageListenerContainer.java:315)
at org.springframework.jms.listener.AbstractPollingMessageListenerContainer.receiveAndExecute(AbstractPollingMessageListenerContainer.java:253)
at org.springframework.jms.listener.DefaultMessageListenerContainer$AsyncMessageListenerInvoker.invokeListener(DefaultMessageListenerContainer.java:1150)
at org.springframework.jms.listener.DefaultMessageListenerContainer$AsyncMessageListenerInvoker.executeOngoingLoop(DefaultMessageListenerContainer.java:1142)
at org.springframework.jms.listener.DefaultMessageListenerContainer$AsyncMessageListenerInvoker.run(DefaultMessageListenerContainer.java:1039)
at java.lang.Thread.run(Unknown Source) Caused by: org.hibernate.TransactionException: Unable to commit against JDBC Connection
at org.hibernate.resource.jdbc.internal.AbstractLogicalConnectionImplementor.commit(AbstractLogicalConnectionImplementor.java:86)
at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl$TransactionDriverControlImpl.commit(JdbcResourceLocalTransactionCoordinatorImpl.java:231)
at org.hibernate.engine.transaction.internal.TransactionImpl.commit(TransactionImpl.java:65)
at org.springframework.orm.hibernate5.HibernateTransactionManager.doCommit(HibernateTransactionManager.java:581)
... 21 more
Caused by: com.microsoft.sqlserver.jdbc.SQLServerException: The connection is closed.
at com.microsoft.sqlserver.jdbc.SQLServerException.makeFromDriverError(SQLServerException.java:190)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.checkClosed(SQLServerConnection.java:388)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.commit(SQLServerConnection.java:1936)
at sun.reflect.GeneratedMethodAccessor150.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.apache.tomcat.jdbc.pool.ProxyConnection.invoke(ProxyConnection.java:126)
at org.apache.tomcat.jdbc.pool.JdbcInterceptor.invoke(JdbcInterceptor.java:108)
at org.apache.tomcat.jdbc.pool.interceptor.ConnectionState.invoke(ConnectionState.java:152)
at org.apache.tomcat.jdbc.pool.JdbcInterceptor.invoke(JdbcInterceptor.java:108)
at org.apache.tomcat.jdbc.pool.interceptor.AbstractCreateStatementInterceptor.invoke(AbstractCreateStatementInterceptor.java:70)
at org.apache.tomcat.jdbc.pool.JdbcInterceptor.invoke(JdbcInterceptor.java:108)
at org.apache.tomcat.jdbc.pool.interceptor.AbstractCreateStatementInterceptor.invoke(AbstractCreateStatementInterceptor.java:70)
at org.apache.tomcat.jdbc.pool.interceptor.ResetAbandonedTimer.invoke(ResetAbandonedTimer.java:62)
at org.apache.tomcat.jdbc.pool.JdbcInterceptor.invoke(JdbcInterceptor.java:108)
at org.apache.tomcat.jdbc.pool.TrapException.invoke(TrapException.java:40)
at org.apache.tomcat.jdbc.pool.JdbcInterceptor.invoke(JdbcInterceptor.java:108)
at org.apache.tomcat.jdbc.pool.DisposableConnectionFacade.invoke(DisposableConnectionFacade.java:81)
at com.sun.proxy.$Proxy21.commit(Unknown Source)
at org.hibernate.resource.jdbc.internal.AbstractLogicalConnectionImplementor.commit(AbstractLogicalConnectionImplementor.java:80)
... 24 more
EDIT 25 / 02 / 2016 : this is what i've implemented but it still doesn't work :
public class ConnectionJDBCInterceptor extends JdbcInterceptor {
protected static Logger log = Logger.getLogger(ConnectionJDBCInterceptor.class.getName());
#Override
public void reset(final ConnectionPool pool, final PooledConnection pooledConnection) {
try {
if (pooledConnection.getConnection().isClosed()) {
ConnectionJDBCInterceptor.log.info("Closed connection in the pool is being reconnected");
pooledConnection.reconnect();
}
} catch (final SQLException e) {
ConnectionJDBCInterceptor.log.error(e, "Error in JDBC Interceptor", e);
}
}
}

I had similar issues. In case of IOException, the sqlserver jdbc driver marks the connection as closed, but this is not detected by the pool. So the connection is returned in the pool, while unusable.
A work around to this is to write a new JDBCInterceptor for tomcatjdbc. The interceptor must when close is invoked, call "isClosed" on the underlying connection. If the underlying connection is closed, the interceptor must marked the PooledConnection as discarded.
Then configure your pool to use this interceptor.

If you don't use Tomcat JDBC pool, then you can exclude it from project and that solves the issue with reconnect.
For gradle:
configurations.all {
exclude group: 'org.apache.tomcat', module: 'tomcat-jdbc'
}

Had this same issue and found a good explanation and solution to the problem here
Summarily, your database or application server (e.g JBoss) connection pool manager has invalidated some connections due to idle timeout settings either set by default or configured explicitly, meanwhile, hibernate's internal database connection pool manager has those connections as valid connections. Hence, when your application tries to reuse them, you get the connection closed error which is not cleared until you restart your application server.
To resolve, simply delegate hibernate connection pool management to a helper library called hibernate-c3p0 and follow an example configuration such as
<property name="hibernate.c3p0.min_size" value="5" />
<property name="hibernate.c3p0.max_size" value="20" />
<property name="hibernate.c3p0.timeout" value="300" />
These properties are well explained in the link above and also here

how to avoid "lock timeout" when updating DB using multiple threads?

I am trying to update a table using multiple threads. But I am not updating the same records/rows at the same time. I am grouping the table into different groups and trying to update them simultaneously. However, I am getting the locked timeout error all the time.
I am using Hibernate, Spring MVC, ThreadPoolTaskExecutor and MySQL. I am getting the data from another DB schema and updating my own database. The data is huge which is why i want to use multi threads so it can be done faster. However, it's producing "lock timeout" error. Can anyone help please? thanks for your good heart.
I call sessionFactory.getCurrenSession() to update the database table.
here is my config:
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
destroy-method="close" p:driverClassName="${jdbc.driverClassName}"
p:url="${jdbc.url}" p:username="${jdbc.username}" p:password="${jdbc.password}">
</bean>
<bean id="sessionFactory"
class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="configLocation">
<value>classpath:hibernate.cfg.xml</value>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>
<prop key="hibernate.show_sql">true</prop>
</props>
</property>
</bean>
<bean id="transactionManager"
class="org.springframework.orm.hibernate4.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory" />
</bean>
<bean id="taskExecutor"
class="org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor">
<property name="corePoolSize" value="5" />
<property name="maxPoolSize" value="10" />
<property name="WaitForTasksToCompleteOnShutdown" value="true" />
</bean>
here is my stacktrace:
WARN : org.hibernate.engine.jdbc.spi.SqlExceptionHelper - SQL Error: 1205, SQLState: 41000
ERROR: org.hibernate.engine.jdbc.spi.SqlExceptionHelper - Lock wait timeout exceeded; try restarting transaction
Exception in thread "taskExecutor-5" Exception in thread "taskExecutor-4" Exception in thread "taskExecutor-2" org.hibernate.exception.LockTimeoutException: could not execute statement
at org.hibernate.dialect.MySQLDialect$1.convert(MySQLDialect.java:407)
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.ResultSetReturnImpl.executeUpdate(ResultSetReturnImpl.java:136)
at org.hibernate.hql.internal.ast.exec.BasicExecutor.execute(BasicExecutor.java:103)
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.executeUpdate(QueryTranslatorImpl.java:413)
at org.hibernate.engine.query.spi.HQLQueryPlan.performExecuteUpdate(HQLQueryPlan.java:282)
at org.hibernate.internal.SessionImpl.executeUpdate(SessionImpl.java:1289)
at org.hibernate.internal.QueryImpl.executeUpdate(QueryImpl.java:116)
org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:96)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:260)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:94)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.sql.SQLException: Lock wait timeout exceeded; try restarting transaction
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1084)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4232)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4164)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2615)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2776)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2838)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2082)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2334)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2262)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2246)
at org.apache.commons.dbcp.DelegatingPreparedStatement.executeUpdate(DelegatingPreparedStatement.java:105)
at org.apache.commons.dbcp.DelegatingPreparedStatement.executeUpdate(DelegatingPreparedStatement.java:105)
at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.executeUpdate(ResultSetReturnImpl.java:133)
... 25 more

A "lock wait timeout" can always happen (even with a large amount of inserts in one transaction) and there is no silver bullet to solve it. But I managed to get around it when I was trying to update half of all the records in one (relative small) table while the other half was being modified by another server.
Review all SQL statements in the transaction.
Use explain to make sure indexes are used where possible. Remove any statements that are not needed as part of the transaction.
Optimize the order of the SQL statements in the transaction.
This was a bit of trial and error for me, but try to imagine which order of SQL statements coming from multiple threads/connections might be easier to deal with for the database. In my case, just switching the order of two SQL statements made the "lock wait timeout" occur less frequent.
Update smaller subsets.
This finally solved the "lock wait timeout" for me. In my case there was an indexed column that allowed me to divide the larger update set into smaller subsets. So now one big update transaction was turned into about ten smaller update transactions. Keep in mind though that you need to be able to continue the smaller transactions after a crash (i.e. data must remain consistent in such a way that your application can redo the operation and have the same result).
Whether or not multiple threads will improve the throughput (updated rows per second) remains to be seen: it depends on the size of the update sets (network latency) and how efficiently MySQL can handle the locks for the table(s) to update the rows. You might only see a marginal improvement when using two threads/connections instead of one.
[Edit] Also watch out for database triggers/procedures: they can impact performance in a bad manner.

Maybe you could try to lower isolation level. If it helps you can dig more. It should speed up also execution in multi threaded environment.
If you are using annotations you can achieve this by
#Transactional(isolation=Isolation.READ_UNCOMMITTED)
on top of your transactional class.

This appears to be a timeout on the database side. I'd guess that the database is the limiting factor, so adding threads in your application doesn't help.
If you want to use threads to speed things up, I'd suggest using only two threads. While one thread reads from the other database, the second thread writes to the MySQL database.
Note that if both databases are on the same database server, even that won't help. You would need a faster database or a beefier database machine.

hibernate exception: transaction roll back failed

When im running my hibernate project in java swing, it works at first. but when i wait for some time and i recieve error like org.hibernate.TransactionException: rollback failed.. tell me a solution for this.
Here is my error
Aug 16, 2013 10:52:21 AM org.hibernate.engine.jdbc.spi.SqlExceptionHelper logExceptions
WARN: SQL Error: 0, SQLState: 08S01
Aug 16, 2013 10:52:21 AM org.hibernate.engine.jdbc.spi.SqlExceptionHelper logExceptions
ERROR: Communications link failure
The last packet successfully received from the server was 89,371 milliseconds ago.
The last packet sent successfully to the server was 1 milliseconds ago.
Exception in thread "AWT-EventQueue-0" org.hibernate.TransactionException: rollback failed
at org.hibernate.engine.transaction.spi.AbstractTransactionImpl.rollback(AbstractTransactionImpl.java:215) at com.softroniics.queenpharma.services.PurchaseOrderService.showAllPurchase(PurchaseOrderService.java:131)
Here is my hibernate cfg 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.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://queenpharma.db.11583306.hostedresource.com/queenpharma</property>
<property name="connection.username">queenpharma</property>
<property name="connection.password">Queenpharma#1</property>
<property name="connection.pool_size">1</property>
<property name="hbm2ddl.auto">update</property>
<property name="show_sql">true</property>
<property name="connection.autocommit">false</property>
<property name="hibernate.c3p0.max_size">1</property>
<property name="hibernate.c3p0.min_size">0</property>
<property name="hibernate.c3p0.timeout">5000</property>
<property name="hibernate.c3p0.max_statements">1000</property>
<property name="hibernate.c3p0.idle_test_period">300</property>
<property name="hibernate.c3p0.acquire_increment">1</property>
<property name="current_session_context_class">thread</property>
<property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>
<mapping class="com.softroniics.queenpharma.model.LoginModel" />
<mapping class="com.softroniics.queenpharma.model.PurchaseCompanyModel" />
---- and so on------
here is some my code
session = sessionFactory.openSession();
StockModel stockModel = null;
try {
tx = session.beginTransaction();
Iterator<StockModel> iterator = session
.createQuery("FROM StockModel where productid='" + id + "'")
.list().iterator();
if(iterator.hasNext()){
stockModel = iterator.next();
}
} catch (HibernateException e) {
if (tx != null)
tx.rollback();
e.printStackTrace();
} finally {
session.close();

The error code you get SQLState: 08S01 suggests that the host name that you use for the database is incorrect according to Mapping MySQL Error Numbers to JDBC SQLState Codes.
So first please make sure that the database host: queenpharma.db.11583306.hostedresource.com is spelled correctly.
If the error persists please modify your exception handler to catch the exception caused by the rollback statement like below so you are able to understand what caused the rollback in the first place.
Note: you should do this only for troubleshooting this issue. You do not want to shallow any exceptions when in a production environment
} catch (HibernateException e) {
if (tx != null) {
try {
tx.rollback();
} catch(Exception re) {
System.err.println("Error when trying to rollback transaction:"); // use logging framework here
re.printStackTrace();
}
}
System.err.println("Original error when executing query:"); // // use logging framework here
e.printStackTrace();
}

It seems like the issue with Mysql connection time out, Guess there would be default time out for Mysql. Refer this article might help you Hibernate Broken pipe
UPDATE
From the hibernate documents
Hibernate's own connection pooling algorithm is, however, quite
rudimentary. It is intended to help you get started and is not
intended for use in a production system, or even for performance
testing. You should use a third party pool for best performance and
stability. Just replace the hibernate.connection.pool_size property
with connection pool specific settings. This will turn off Hibernate's
internal pool. For example, you might like to use c3p0.
So you no need to specify the hibernate connection pool size property when you are using c3p0 connection pooling

Remember committing and closing the session. It might will be that you do not commit and Hibernate tries a rollback after the connection has already timed out.
It would be helpful to see how you access the DB, please post some code.

PostgreSQL + Hibernate + C3P0 = FATAL: sorry, too many clients already

I have the following code
Configuration config = new Configuration().configure();
config.buildMappings();
serviceRegistry = new ServiceRegistryBuilder().applySettings(config.getProperties()).buildServiceRegistry();
SessionFactory factory = config.buildSessionFactory(serviceRegistry);
Session hibernateSession = factory.openSession();
Transaction tx = hibernateSession.beginTransaction();
ObjectType ot = (ObjectType)hibernateSession.merge(someObj);
tx.commit();
return ot;
hibernate.cfg.xml contains:
<session-factory>
<property name="connection.url">jdbc:postgresql://127.0.0.1:5432/dbase</property>
<property name="hibernate.dialect">org.hibernate.dialect.PostgreSQLDialect</property>
<property name="connection.driver_class">org.postgresql.Driver</property>
<property name="connection.username">username</property>
<property name="connection.password">password</property>
<property name="connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>
<property name="hibernate.c3p0.acquire_increment">1</property>
<property name="hibernate.c3p0.min_size">5</property>
<property name="hibernate.c3p0.max_size">20</property>
<property name="hibernate.c3p0.max_statements">50</property>
<property name="hibernate.c3p0.timeout">300</property>
<property name="hibernate.c3p0.idle_test_period">3000</property>
<property name="hibernate.c3p0.acquireRetryAttempts">1</property>
<property name="hibernate.c3p0.acquireRetryDelay">250</property>
<property name="hibernate.show_sql">true</property>
<property name="hibernate.use_sql_comments">true</property>
<property name="hibernate.transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory</property>
<property name="hibernate.current_session_context_class">thread</property>
<mapping class="...." />
</session-factory>
After a few seconds and some successful inserts, the following exception appears:
org.postgresql.util.PSQLException: FATAL: sorry, too many clients already
at org.postgresql.core.v3.ConnectionFactoryImpl.doAuthentication(ConnectionFactoryImpl.java:291)
at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:108)
at org.postgresql.core.ConnectionFactory.openConnection(ConnectionFactory.java:66)
at org.postgresql.jdbc2.AbstractJdbc2Connection.<init>(AbstractJdbc2Connection.java:125)
at org.postgresql.jdbc3.AbstractJdbc3Connection.<init>(AbstractJdbc3Connection.java:30)
at org.postgresql.jdbc3g.AbstractJdbc3gConnection.<init>(AbstractJdbc3gConnection.java:22)
at org.postgresql.jdbc4.AbstractJdbc4Connection.<init>(AbstractJdbc4Connection.java:30)
at org.postgresql.jdbc4.Jdbc4Connection.<init>(Jdbc4Connection.java:24)
at org.postgresql.Driver.makeConnection(Driver.java:393)
at org.postgresql.Driver.connect(Driver.java:267)
at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:135)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
12:24:19.151 [ Thread-160] WARN internal.JdbcServicesImpl - HHH000342: Could not obtain connection to query metadata : Connections could not be acquired from the underlying database!
12:24:19.151 [ Thread-160] INFO dialect.Dialect - HHH000400: Using dialect: org.hibernate.dialect.PostgreSQLDialect
12:24:19.151 [ Thread-160] INFO internal.LobCreatorBuilder - HHH000422: Disabling contextual LOB creation as connection was null
12:24:19.151 [ Thread-160] INFO internal.TransactionFactoryInitiator - HHH000268: Transaction strategy: org.hibernate.engine.transaction.internal.jdbc.JdbcTransactionFactory
12:24:19.151 [ Thread-160] INFO ast.ASTQueryTranslatorFactory - HHH000397: Using ASTQueryTranslatorFactory
12:24:19.151 [ Thread-160] INFO hbm2ddl.SchemaUpdate - HHH000228: Running hbm2ddl schema update
12:24:19.151 [ Thread-160] INFO hbm2ddl.SchemaUpdate - HHH000102: Fetching database metadata
12:24:19.211 [Runner$PoolThread-#0] WARN resourcepool.BasicResourcePool - com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask#ee4084 -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (1). Last acquisition attempt exception:
org.postgresql.util.PSQLException: FATAL: sorry, too many clients already
at org.postgresql.core.v3.ConnectionFactoryImpl.doAuthentication(ConnectionFactoryImpl.java:291)
It seems that the hibernate doesn't realse the connection. But hibernateSession.close() causes exception Session is closed because tx.commit() is called.

I'm not quite sure what's going on here, but I'd recommend you not set hibernate.c3p0.acquireRetryAttempts to 1. First, that renders your next setting, hibernate.c3p0.acquireRetryDelay irrelevant -- that sets the length of time between retry attempts, but if there is only one attempt (ok, the param name is misleading, it sets the total number of tries), there are no retries. The effect of your settings is simply to have the pool try to fetch a Connection whenever a client comes in, then throw an Exception to clients immediately if that fails. It doesn't at all limit the number of Connections the pool will try to acquire (unless you set breakOnAcquireFailure to true, in which case, with your settings, any failure to acquire a Connection would invalidate the whole pool).
I share sola's concern about your lack of reliable resource cleanup. If, under your settings, commit() means close() (and you are not allowed to call close explicitly? that seems bad), then it is commit that should be in the finally block (but commit in a finally block also seems bad, sometimes you don't want to commit). Whatever the issue with close/commit, with the code you have, occasional Exceptions between openSession and commit will lead to Connection leaks.
But that should not be the cause of your too-many-open-Connections problem. If you leak Connections, you'll find that the Connection pool eventually freezes (as maxPoolSize Connectiosn are checked out forever due to the leaks). You'd only have 25 open Connections. Something else is going on. Try reviewing your logs. Is more than one Connection pool somehow being initialized? (c3p0 dumps config information at INFO level on pool init, so if multiple pools are getting opened, you should see multiple messages. alternatively, you can inspect running c3p0 pools via JMX, to see whether/why more than 25 Connections have been opened.)
Good luck!

I found the cause why c3p0 behaved in this way.The issue was quite trivial...
This part of code:
Configuration config = new Configuration().configure();
config.buildMappings();
serviceRegistry = new ServiceRegistryBuilder().applySettings(config.getProperties()).buildServiceRegistry();
SessionFactory factory = config.buildSessionFactory(serviceRegistry);
was executed multiple times. Thank you Steve for the tip.

I'm suggesting you to use try-catch-finally block,
in finally kindly close the session
i.e
try {
tx.commit();
} catch (HibernateException e) {
handleException(e);
} finally {
hibernateSession.close();
}
and also,
the max_connections property in postgresql.conf it's 100 by default. Increase it if you need.

Spring JDBCTemplate other MySQL datasource than apache commons?

I am using Spring JDBCTemplate to perform SQL operations on an apache commons datasource (org.apache.commons.dbcp.BasicDataSource) and when the service is up and running to long, i end up getting this exception:
org.springframework.dao.RecoverableDataAccessException: StatementCallback; SQL [SELECT * FROM vendor ORDER BY name]; The last packet successfully received from the server was 64,206,061 milliseconds ago. The last packet sent successfully to the server was 64,206,062 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.; nested exception is com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The last packet successfully received from the server was 64,206,061 milliseconds ago. The last packet sent successfully to the server was 64,206,062 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 org.springframework.jdbc.support.SQLExceptionSubclassTranslator.doTranslate(SQLExceptionSubclassTranslator.java:98)
at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:72)
at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:80)
at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:406)
at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:455)
at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:463)
at com.cable.comcast.neto.nse.taac.dao.VendorDao.getAllVendor(VendorDao.java:25)
at com.cable.comcast.neto.nse.taac.controller.RemoteVendorAccessController.requestAccess(RemoteVendorAccessController.java:78)
I have tried adding the 'autoReconnect=true' to the connection string, but this problem still occurs. Is there another datasource that can be used that will manage the reconnecting for me?

BasicDataSource can manage keeping the connections alive for you. You need to set the following properties :
minEvictableIdleTimeMillis = 120000 // Two minutes
testOnBorrow = true
timeBetweenEvictionRunsMillis = 120000 // Two minutes
minIdle = (some acceptable number of idle connections for your server)
These will configure the data source to keep continually test your connections, and expire and remove them if they become stale. There's a number of other properties on the basic data source that you may want to consider checking into as well to tweak your connection pooling performance. I've run into some strange problems in the past where I was having issues with my database access and it all came down to how the connection pool was configured.

You can try to C3PO:
http://sourceforge.net/projects/c3p0/
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"destroy-method="close">
<property name="user" value="${db.username}"/>
<property name="password" value="${db.password}"/>
<property name="driverClass" value="${db.driverClassName}"/>
<property name="jdbcUrl" value="${db.url}"/>
<property name="initialPoolSize" value="0"/>
<property name="maxPoolSize" value="1"/>
<property name="minPoolSize" value="1"/>
<property name="acquireIncrement" value="1"/>
<property name="acquireRetryAttempts" value="0"/>
<property name="idleConnectionTestPeriod" value="600"/> <!--in seconds-->
</bean>
grettings
pacovr