No JDBC Driver class was specified by property hibernate.connection.driver_class - spring

Question

With this Pom.xml:
<!-- Hibernate resources -->
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>4.2.1.Final</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-c3p0</artifactId>
<version>4.1.6.Final</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>${org.springframework-version}</version>
</dependency>
And With this context xml:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:tx="http://www.springframework.org/schema/tx" xmlns:xsi="http://www.w3.org /2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-3.2.xsd">
<!-- Root Context: defines shared resources visible to all other web components -->
<bean id="transactionManager"
class="org.springframework.orm.hibernate4.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory" />
</bean>
<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/x" />
<property name="user" value="x" />
<property name="password" value="x" />
<!-- these are C3P0 properties -->
<property name="acquireIncrement" value="5" />
<property name="minPoolSize" value="2" />
<property name="maxPoolSize" value="5" />
<property name="maxIdleTime" value="1800" />
</bean>
<bean id="sessionFactory"
class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="dataSource" ref="dataSource"></property>
<property name="packagesToScan" value="src.com.x.model.entities"></property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.hbm2ddl.auto">update</prop>
<!-- configuration pool via c3p0 -->
<prop key="hibernate.connection.provider_class">org.hibernate.service.jdbc.connections.internal.C3P0ConnectionProvider</prop>
<prop key="hibernate.c3p0.acquire_increment">5</prop>
<prop key="hibernate.c3p0.idle_test_period">1800</prop>
<prop key="hibernate.c3p0.max_size">600</prop>
<prop key="hibernate.c3p0.max_statements">50</prop>
<prop key="hibernate.c3p0.min_size">5</prop>
<prop key="hibernate.c3p0.timeout">1800</prop>
</props>
</property>
</bean>
<tx:annotation-driven transaction-manager="transactionManager"
proxy-target-class="true" />
after im starting my server i get the following exception:
WARN : org.hibernate.service.jdbc.connections.internal.C3P0ConnectionProvider - HHH000148: No JDBC Driver class was specified by property hibernate.connection.driver_class
WARN : com.mchange.v2.async.ThreadPoolAsynchronousRunner - com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector#724ccdfe -- APPARENT DEADLOCK!!! Creating emergency threads for unassigned pending tasks!
WARN : com.mchange.v2.async.ThreadPoolAsynchronousRunner - com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector#724ccdfe -- APPARENT DEADLOCK!!! Complete Status:
what am i doing wrong here?
I'm using spring 3 and hibernate 4,
unfortunately i couldn't find this exact same error message in Google so i guess that means trouble
thanks!

Answer 1

You should not mix these versions. Use:
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>4.2.1.Final</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-c3p0</artifactId>
<version>4.2.1.Final</version>
</dependency>
or even better:
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>${hibernateOrmVersion}</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-c3p0</artifactId>
<version>${hibernateOrmVersion}</version>
</dependency>
and define hibernateOrmVersion as a POM property