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Tomcat connection pool issue- Cannot call a method on closed connection

My application is using Spring 2.5.x and deployed on Tomcat server. Some times, I get below error when my db connection is idle:
[TeraJDBC 14.00.00.13] [Error 1095] [SQLState HY000] Cannot call a
method on closed connection
Here is the datasource configuration
<bean id="dataSource" class="org.apache.tomcat.jdbc.pool.DataSource"
destroy-method="close">
<property name="driverClassName" value="com.teradata.jdbc.TeraDriver"/>
<property name="url" >
<util:constant static-field="_DB_HOST"/>
</property>
<property name="username">
<util:constant static-field="_DB_USER"/>
</property>
<property name="password">
<util:constant static-field="_DB_PWD"/>
</property>
<property name="initialSize" value="1" />
<property name="maxActive" value="50" />
</bean>
Is there any configuration I'm missing here?

While all connections used by Spring's JdbcTemplate are closed at the end of each transaction, Tomcat's JDBC Connection Pool never actually returns the real Connection's obtained by the driver. DataSource#getConnection always returns a proxy, such that Connection#close returns the connection to the pool instead of physically closing it.
Therefore, as explained in this answer, the connections are probably closed by the server. Therefore you need to configure the pool to validate the connections, as in the answer cited by Kayaman.
I suspect that your problem is not caused by connection issues, but server policy, so I would set up:
<property name="validationQuery" value="SELECT 66353343" />
<property name="testWhileIdle" value="true" />
<property name="timeBetweenEvictionRunsMillis" value="60000" />
in order to check every 60 seconds if the physical connections are up.

Spring JDBC connections left open

I'm using the following bean to connect to the DB through JDBC:
<bean id="databaseds" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
<property name="driverClassName" value="${jdbc.driverClassName}"/>
<property name="url" value="${jdbc.url}"/>
<property name="removeAbandoned" value="true"/>
<property name="initialSize" value="1" />
<property name="maxActive" value="2" />
<property name="maxIdle" value="0" />
<property name="minEvictableIdleTimeMillis" value="120000" />
</bean>
Using quartz a new class is constructed which takes advantage of Spring JDBC to run SQL statements. What I did notice is that most of the the JDBC connections are still hanging around hours after the quartz job ran and completed. Based on the bean I'm expecting to have NO idle sessions 2-3 minutes after the connection is not being used.
Am I missing anything? I don't want to keep more than 1-2 connections open to the database, the program is not doing any DB intensive work but does run every 30 minutes and if the connections are not reused or closed they pile up.

Tomcat JDBC Conencton Pool + MySQL gives "Broken pipe" problems, even with connection validation

I'm fighting with configuring Tomcat JDBC Connection Pool to achieve reliability. Current issue is that in test environment I have such scanerio in webapp:
day 1: everything works fine
day 2: webapp cannot comunicate with MySQL for several hours, lot of "Broken pipe" in logs
day 3: suprisingly, everything works fine again (without ingerention or restart)
I have configured validationInterval, validationQuery, validationTimeout. This is my data source config:
<bean id="dataSource" class="org.apache.tomcat.jdbc.pool.DataSource"
destroy-method="close">
<property name="driverClassName" value="com.mysql.jdbc.Driver" />
<property name="username" value="${dbUser}" />
<property name="password" value="${dbPass}" />
<property name="url" value="${dbUrl}" />
<property name="defaultAutoCommit" value="false" />
<property name="defaultTransactionIsolation">
<util:constant static-field="java.sql.Connection.TRANSACTION_SERIALIZABLE" />
</property>
<property name="maxActive" value="300" />
<property name="maxIdle" value="25" />
<property name="initialSize" value="5" />
<property name="validationInterval" value="5000" />
<property name="validationQuery" value="SELECT 1"/>
<property name="validationQueryTimeout" value="3" />
<property name="minIdle" value="5" />
<property name="initSQL" value="SET time_zone = '+00:00';" />
</bean>
I don't have autoReconnect=true parameter in connection URL, only UTF8 encoding.
The exact error is:
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException:
The last packet successfully received from the server was 38,700,615
milliseconds ago. The last packet sent successfully to the server was
38,700,615 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.
Caused by: java.net.SocketException: Broken pipe

We had some similar problems with one of our applications and after a lot of digging we added the following properties that solved all our connection problems:
maxAge="180000"
testOnBorrow="true"
testWhileIdle="true"
validationInterval="0" //forces the connection pool to validate each time a connection is given to the application

You need to set 'testOnBorrow' to 'true', and probably 'maxAge' to less than the server's configured 'wait_timeout', as hinted in the message.

Max User Connection issue with Hibernate and Java [duplicate]

This question already has an answer here:
User root already has more than 'max_user_connections' active connections in Hibernate
(1 answer)
Closed 3 years ago.
I am using following code for database connection with Hibernate and Java specified in my applicationcontext file,
<bean id="DataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">
<property name="driverClass" value="com.mysql.jdbc.Driver" />
<property name="jdbcUrl" value="jdbc:mysql://localhost:3306/database?useUnicode=true&characterEncoding=UTF-8" />
<property name="user" value="admin" />
<property name="password" value="pass" />
<property name="maxPoolSize" value="10" />
<property name="maxStatements" value="10" />
<property name="minPoolSize" value="5" />
<property name="initialPoolSize" value="10" />
<property name="maxIdleTime" value="120" />
<property name="numHelperThreads" value="1" />
<property name="preferredTestQuery" value="SELECT 1" />
</bean>
on the server after sometime it gives following error
com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask run
WARNING:
com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask#198c333 --
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 (30).
Last acquisition attempt exception: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: User admin already has more than 'max_user_connections' active connections
can anyone let me know where I m going wrong

It looks like you have a configuration problem with your database. It's likely that your database couldn't let to the same user 10 simultanious connections. Maybe you could try to reduce maxPoolSize and minPoolSize to 1 so you can see your real problem.(Since the exception that you see is just the last exception given)

Take a loot at these urls:
How To Configure DBCP Connection Pool In Hibernate
How To Configure The C3P0 Connection Pool In Hibernate
Hope it helps.

Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException

Getting below exception on my prod server, but it resolves automatically after few hours. What could be the reason for this issue
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The last packet successfully received from the server was234747 milliseconds ago.The last packet sent successfully to the server was 234747 milliseconds ago, which 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.
We have set autoReconnect=true already, From Forums I found that we need enable idle connections test. Please advise
Will it be any unclosed connections in the application causes this exception?
we use Ibatis and below is the Ibatisconfig file
<transactionManager type="JDBC" commitRequired="true">
<dataSource type="SIMPLE">
<property name="JDBC.Driver" value="com.mysql.jdbc.Driver" />
<property name="JDBC.ConnectionURL"
value="<URL>?autoReconnect=true" />
<property name="JDBC.Username" value="<username>" />
<property name="JDBC.Password" value="<password>" />
<property name="JDBC.DefaultAutoCommit" value="false" />
<property name="Pool.TimeToWait" value="100" />
<property name="Pool.PingQuery" value="select 1" />
<property name="Pool.PingEnabled" value="true" />
<property name="Pool.PingConnectionsOlderThan" value="300000" />
<property name="Pool.PingConnectionsNotUsedFor" value="300000" />
</dataSource>
</transactionManager>

Well, in my project I faced the same issue. We use mysql, and if the connection is idle for 8 hours then db goes unavailable. The solution we used was using C3P0 connection pool. Check about this in here.
http://www.mchange.com/projects/c3p0/