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Java.sql.SQLException: already closed

We have a webapp running on tomcat with MySQL support. At one point, everything was fine, and suddenly we started getting this exceptionjava.sql.SQLException: Already closed.

All stack trace:

DEBUG [org.springframework.jdbc.datasource.DataSourceUtils] Fetching JDBC Connection from DataSource
DEBUG [org.springframework.jdbc.datasource.DataSourceUtils] Returning JDBC Connection to DataSource
DEBUG [org.springframework.jdbc.datasource.DataSourceUtils] Could not close JDBC Connection    
java.sql.SQLException: Already closed.
    at org.apache.commons.dbcp.PoolableConnection.close(PoolableConnection.java:114)
    at org.apache.commons.dbcp.PoolingDataSource$PoolGuardConnectionWrapper.close(PoolingDataSource.java:191)
    at org.springframework.jdbc.datasource.DataSourceUtils.doReleaseConnection(DataSourceUtils.java:333)
    at org.springframework.jdbc.datasource.DataSourceUtils.releaseConnection(DataSourceUtils.java:294)
    at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:405)
    at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:428)
    at com.nokia.analytics.aws.aggregate.service.importer.DBInsert.truncateTable(DBInsert.java:135)
    at com.blah.analytics.aggregate.service.importer.AggregateCollector.pullAndInsert(AggregateCollector.java:85)
    at com.blah.analytics.aggregate.service.importer.AggregateCollector.call(AggregateCollector.java:96)
    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
    at java.util.concurrent.FutureTask.run(FutureTask.java:166)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1146)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:679)

We use org.apache.commons.dbcp.BasicDataSourceas our data source. I searched quite a lot, but to no avail. This does not always happen and therefore is very difficult to reproduce. There seems to be a problem with the db connection pool. Somewhere it was suggested to set this parameter as negative. We do not currently change these parameters (all have default values).

What approach should be followed to avoid this?

EDIT:

The corresponding code is in (DBInsert.java)

133: String sql = "DELETE FROM "+tableName;

134: logger.debug(sql);

135: this.jdbcTemplate.execute(sql);

(133-135 are line numbers that are indicated in the exception)

My data source configuration:

<bean id="bisToolDataSource" class="org.apache.commons.dbcp.BasicDataSource"
        destroy-method="close">
        <property name="driverClassName" value="com.mysql.jdbc.Driver" />
        <property name="url"
            value="${url}/blah_db?verifyServerCertificate=false&amp;useSSL=true&amp;requireSSL=true" />
        <property name="username" value="${uname}" />
        <property name="password" value="${passwd}" />
    </bean>
+5
2

, , testOnBorrow validationQuery , .
:)

+13

NobodyElse, . org.apache.commons.dbcp.BasicDataSource . , . - , , .

: , NobodyElse, testOnBorrow;

( ) - . , , DB ( ). org.springframework.jdbc.datasource.DriverManagerDataSource. , :

<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver" />
        <property name="url"
            value="${url}/blah_db?verifyServerCertificate=false&amp;useSSL=true&amp;requireSSL=true" />
        <property name="username" value="${uname}" />
        <property name="password" value="${passwd}" />
</bean>
+6

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