Conflict with Hibernate's Pool and Mysql?

[Ben Anis]

hello, is there conflict with Hibernate's Pool and Mysql? I have a web application in mysql and I use hibernate for the management of connexion.but after hours of use of the applications I have an exception when connecting:

org.hibernate.exception.GenericJDBCException: Cannot open connection
    at org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:103)
    at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:91)
    at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
    at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:29)
    at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:426)
    at org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:144)
    at org.hibernate.jdbc.JDBCContext.connection(JDBCContext.java:119)
    at org.hibernate.transaction.JDBCTransaction.begin(JDBCTransaction.java:57)
    at org.hibernate.impl.SessionImpl.beginTransaction(SessionImpl.java:1326)
    at big.commun.data.BigObjet.getSession(BigObjet.java:1808)
    at big.commun.auth.BigAuth.getSession(BigAuth.java:69)
    at big.commun.auth.BigAuth.SelectUser(BigAuth.java:159)
    at big.commun.auth.BigAuthAction.processRequest(BigAuthAction.java:46)
    at auth.AuthAction.processRequest(AuthAction.java:22)
    at big.commun.data.BigActionServer.doPost(BigActionServer.java:251)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
    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:175)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
    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:263)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:584)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
    at java.lang.Thread.run(Thread.java:619)
Caused by: java.sql.SQLException: An SQLException was provoked by the following failure: java.lang.InterruptedException
    at com.mchange.v2.sql.SqlUtils.toSQLException(SqlUtils.java:106)
    at com.mchange.v2.sql.SqlUtils.toSQLException(SqlUtils.java:65)
    at com.mchange.v2.sql.SqlUtils.toSQLException(SqlUtils.java:62)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutPooledConnection(C3P0PooledConnectionPool.java:531)
    at com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource.getConnection(AbstractPoolBackedDataSource.java:128)
    at org.hibernate.connection.C3P0ConnectionProvider.getConnection(C3P0ConnectionProvider.java:56)
    at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:423)
    ... 24 more
Caused by: java.lang.InterruptedException
    at java.lang.Object.wait(Native Method)
    at com.mchange.v2.resourcepool.BasicResourcePool.awaitAvailable(BasicResourcePool.java:1315)
    at com.mchange.v2.resourcepool.BasicResourcePool.prelimCheckoutResource(BasicResourcePool.java:557)
    at com.mchange.v2.resourcepool.BasicResourcePool.checkoutResource(BasicResourcePool.java:477)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutPooledConnection(C3P0PooledConnectionPool.java:525)
    ... 27 more

What could be the reason for this error?


This is my hibernate configuration file :

<?xml version='1.0' encoding='UTF-8'?> <!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">


<hibernate-configuration>
<session-factory>
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="show_sql">true</property>
<property name="max_fetch_depth">3</property>
<property name="connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>
<property name="c3p0.acquire_increment">2</property>
<property name="c3p0.idle_test_period">3000</property>
<property name="c3p0.timeout">1800</property>
<property name="c3p0.max_size">25</property>
<property name="c3p0.min_size">3</property>
<property name="c3p0.max_statement">0</property>
<property name="c3p0.preferredTestQuery">select 1;</property>
<property name="c3p0.validate">true</property>
<property name="myeclipse.connection.profile">MysqlS2</property>
<session-factory>
<hibernate-configuration>

Regards.

[Waswani Naresh]

Hi Ben,

Looks like the connection pool is out of DB connections. Reason could be that the connections were not released properly i.e. session objects were not release/closed properly.

Could you please check if the session objects were closed properly after the transactions were over ?

Regards,
Naresh Waswani

[Ben Anis]

Hi Naresh ,
Normally all connections are closed after each transaction.
Regards.

[Ben Anis]

I got even more detailed than:

org.hibernate.exception.GenericJDBCException: Cannot open connection
	at org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:103)
	at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:91)
	at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
	at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:29)
	at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:426)
	at org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:144)
	at org.hibernate.jdbc.JDBCContext.connection(JDBCContext.java:119)
	at org.hibernate.transaction.JDBCTransaction.begin(JDBCTransaction.java:57)
	at org.hibernate.impl.SessionImpl.beginTransaction(SessionImpl.java:1326)
	at big.commun.data.BigObjet.getSession(BigObjet.java:1826)
	at big.commun.auth.BigAuth.getSession(BigAuth.java:68)
	at big.commun.auth.BigAuth.SelectUserPermission(BigAuth.java:142)
	at big.commun.auth.BigAuthAction.processRequest(BigAuthAction.java:58)
	at auth.AuthAction.processRequest(AuthAction.java:22)
	at big.commun.data.BigActionServer.doPost(BigActionServer.java:251)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
	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:175)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
	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:263)
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:584)
	at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
	at java.lang.Thread.run(Thread.java:619)
Caused by: java.sql.SQLException: Connections could not be acquired from the underlying database!
	at com.mchange.v2.sql.SqlUtils.toSQLException(SqlUtils.java:106)
	at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutPooledConnection(C3P0PooledConnectionPool.java:529)
	at com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource.getConnection(AbstractPoolBackedDataSource.java:128)
	at org.hibernate.connection.C3P0ConnectionProvider.getConnection(C3P0ConnectionProvider.java:56)
	at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:423)
	... 24 more
Caused by: com.mchange.v2.resourcepool.CannotAcquireResourceException: A ResourcePool could not acquire a resource from its primary factory or source.
	at com.mchange.v2.resourcepool.BasicResourcePool.awaitAvailable(BasicResourcePool.java:1319)
	at com.mchange.v2.resourcepool.BasicResourcePool.prelimCheckoutResource(BasicResourcePool.java:557)
	at com.mchange.v2.resourcepool.BasicResourcePool.checkoutResource(BasicResourcePool.java:477)
	at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutPooledConnection(C3P0PooledConnectionPool.java:525)

So the cause is :

Caused by: com.mchange.v2.resourcepool.CannotAcquireResourceException: A ResourcePool could not acquire a resource from its primary factory or source.

What explanation given in this case.

[Ben Anis]

For further identified the problem I add this: When it is blocked from the deployed application on the net, if I access the same database but with a deployed application on my computer, I have no problem connecting. So if I open a connection tool database (sql manager), I have no problem to run queries. So it's not a problem transaction not closed.