Database Connections Not Closing

Question

I'm using iBatis for PostgreSQL database access and frequently have problems with connections not being closed. Here is a copy of my sqlMapConfig file:
============================
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE sqlMapConfig
PUBLIC "-//iBATIS.com//DTD SQL Map Config 2.0//EN"
"http://www.ibatis.com/dtd/sql-map-config-2.dtd">
<sqlMapConfig>
<properties resource="ibatis.properties" />
<settings
lazyLoadingEnabled="true"
cacheModelsEnabled="true"
enhancementEnabled="false"
useStatementNamespaces="false"
/>
<transactionManager type="JDBC" commitRequired="true">
<dataSource type="DBCP">
<property name="driverClassName" value="${driver}" />
<property name="url" value="${url}" />
<property name="username" value="${username}" />
<property name="password" value="${password}" />
<property name="maxActive" value="10"/>
<property name="maxIdle" value="5"/>
<property name="maxWait" value="5000"/>
<property name="logAbandoned" value="true"/>
<property name="removeAbandoned" value="true"/>
<property name="removeAbandonedTimeout" value="1"/>
<property name="Driver.logUnclosedConnections" value="true"/>
</dataSource>
</transactionManager>
<sqlMap resource="job-sqlMap.xml" />
</sqlMapConfig>
============================
Due to the logAbandoned and removeAbandoned settings, I get a report in my log file whenever there is a connection that was not properly closed. Here is one of those log entries:
23:22:51.483 (10) Finalizing a Connection that was never closed:
java.lang.Throwable: Connection was created at this point:
at org.postgresql.jdbc2.AbstractJdbc2Connection.<init>(AbstractJdbc2Connection.java:175)
at org.postgresql.jdbc3.AbstractJdbc3Connection.<init>(AbstractJdbc3Connection.java:30)
at org.postgresql.jdbc3.Jdbc3Connection.<init>(Jdbc3Connection.java:24)
at org.postgresql.Driver.makeConnection(Driver.java:393)
at org.postgresql.Driver.connect(Driver.java:267)
at org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:38)
at org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:294)
at org.apache.commons.pool.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:1148)
at org.apache.commons.dbcp.AbandonedObjectPool.borrowObject(AbandonedObjectPool.java:84)
at org.apache.commons.dbcp.PoolingDataSource.getConnection(PoolingDataSource.java:96)
at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:880)
at com.ibatis.sqlmap.engine.transaction.jdbc.JdbcTransaction.init(JdbcTransaction.java:48)
at com.ibatis.sqlmap.engine.transaction.jdbc.JdbcTransaction.getConnection(JdbcTransaction.java:89)
at com.ibatis.sqlmap.engine.mapping.statement.MappedStatement.executeQueryForList(MappedStatement.java:139)
at com.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.queryForList(SqlMapExecutorDelegate.java:567)
at com.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.queryForList(SqlMapExecutorDelegate.java:541)
at com.ibatis.sqlmap.engine.impl.SqlMapSessionImpl.queryForList(SqlMapSessionImpl.java:118)
at com.ibatis.sqlmap.engine.impl.SqlMapClientImpl.queryForList(SqlMapClientImpl.java:94)
at edu.calpoly.lib.multimedia.big.db.AutomaticPeriodUpdateIBatisImplDBHandler.getGamesWithAutomaticUpdatePolicy(AutomaticPeriodUpdateIBatisImplDBHandler.java:154)
at edu.calpoly.lib.multimedia.big.game.AutoUpdateThread.run(AutoUpdateThread.java:155)
The file: AutomaticPeriodUpdateIBatisImplDBHandler.java contains an iBatis call on line # 154:
--> list = sqlMap.queryForList("getGamesWithAutoPolicy", null);
from the map file:
<select id="getGamesWithAutoPolicy" resultClass="java.util.HashMap">
<![CDATA[
SELECT gameid, policy
FROM update_policy
]]>
</select>
Here is the code for the entire method that uses this transaction:
============================
public List getGamesWithAutomaticUpdatePolicy() throws BIGDatabaseFacadeException
List list = new ArrayList();
try
sqlMap.startTransaction();
list = sqlMap.queryForList("getGamesWithAutoPolicy", null);
sqlMap.commitTransaction();
catch(SQLException sqle)
throw new BIGDatabaseFacadeException(sqle);
finally
try
sqlMap.endTransaction();
catch(SQLException sqle)
throw new BIGDatabaseFacadeException(sqle);
return list;
============================
I know that this should be handled as an automatic transaction, but I tried adding the start, commit and end transaction commands in my desperate attempt to fix this problem (but it still didn't help).
Here is my code for creation of sqlMap -
--> sqlMap = SqlMapClientBuilder.buildSqlMapClient(Resources.getResourceAsReader("sqlMaps.xml"));
Except for the fact that occasionally connections are not closed, overall my database access using iBatis works very well.
In the course of trying to fix this problem I've worked to update all my lib files to the latest versions, and here is current status:
My iBatis lib file: ibatis-2.3.4.726.jar
My JDBC driver: postgresql-8.4-701.jdbc3.jar
Required commons files:
commons-dbcp-1.2.2.jar
commons-pool-1.5.3.jar
Note that I tried adding --> commitRequired="true" to the transactionManager in sqlMaps.xml, hoping it might help, but no joy.
Please help me figure out why my database connections often do not close. Thank you very much!

Answer 1

I'm sorry, but I don't understand what you mean by "close the session." I believe iBatis is supposed to take care of all that automatically. My understanding is that all the user does is create the sqlMapClient and then use it along with various map files to query and update the database. iBatis does the rest.