Spring MVC & Hibernate stops working after 8 hours - mysql

Question

The following xml config file stops working after 8 hours of inactivity with this Error:
ERROR: Already closed.
25-may-2017 8:45:23 org.apache.catalina.core.StandardWrapperValve invoke
Servlet.service() for servlet [dispatcher] in the context with path [/system] threw exception [Request processing failed; nested exception is org.springframework.transaction.CannotCreateTransactionException: Could not open Hibernate Session for transaction; nested exception is org.hibernate.TransactionException: JDBC begin transaction failed: ] with root cause:
java.net.SocketException: **Software caused connection abort: recv failed**
Below is the Configuration file:
<context:component-scan base-package="es.company.system.persistence" />
<bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="packagesToScan" value="es.mypackage.model"></property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</prop>
<prop key="hibernate.show_sql">false</prop>
</props>
</property>
</bean>
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">
<property name="connection.driver_class" value="com.mysql.jdbc.Driver" />
<property name="connection.url" value="jdbc:mysql://localhost:3306/system" />
<property name="connection.username" value="???" />
<property name="connection.password" value="???" />
<property name="hibernate.c3p0.min_size" value="5" />
<property name="hibernate.c3p0.max_size" value="20" />
<property name="hibernate.c3p0.timeout" value="1800"/>
<property name="hibernate.c3p0.max_statements" value="50" />
<property name="hibernate.c3p0.testConnectionOnCheckout" value="true" />
<property name="hibernate.c3p0.privilegeSpawnedThreads" value="true" />
<property name="hibernate.c3p0.contextClassLoaderSource" value="library" />
</bean>
<bean id="transactionManager"
class="org.springframework.orm.hibernate4.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory" />
</bean>
<bean id="persistenceExceptionTranslationPostProcessor"
class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor" />
<tx:annotation-driven transaction-manager="transactionManager" />
I'm currently using Spring MVC 4.3.8 and Hibernate 4.1.9. with C3P0 conections pool for MySQL. I thought with C3P0 this would be solved, but it's not.
Anyone knows what's wrong?
Thanks!!!

Answer 1

Software caused connection abort: recv failed --
This usually means that there was a network error, such as a TCP timeout.
also set timeout param with default = 0 for hibernate.c3p0.timeout
hibernate.c3p0.timeout – When an idle connection is removed from the
pool (in second). Hibernate default: 0, never expire.
set autoReconnect , hibernate.c3p0.autoReconnect = true or as url connection param : jdbc:mysql://localhost:3306/test?autoReconnect=true
Add < property name="hibernate.c3p0.preferredTestQuery">SELECT 1</property>
and check it log that c3p0 execute it(if not add real select count(1) from real table with limit 1). Also check your network timeout

Answer 2

I have experienced this issues some time google cloud sql where the SQL server breaks all the connection after idle time out of 10 hrs. But in the application we still have the sessionFactory instance and can create sessions but when you actually fire a db query it fails with broken connection exception.
None of the below attempts worked.
1. auto reconnect set in connection url
2. auto reconnect, timeout, validation properties in xml file.
3. Wrote a polling service to make a jdbc call to keep the connection active for every 8 hrs (<10 hrs idle time out period)
4. Closed and opened new sessionFactory for every db operation.
Finally i have created a polling service which will shutdown the sessiongFactory and create a new one.
NOTE: Calling close method on sessionFactory object is not sufficient. You need to explicit set it to null;
This may be a workaround but it saved me from day restart of the application.
I was not using spring just rest service with hibernate.