@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = {"file:src/test/resources/applicationContext.xml"})
@Transactional
@WebAppConfiguration
public class ServiceTest {

private static DataSource ds;

@BeforeClass
public static void setUpConnection(){
    ds = new DataSource();
    ds.setDriverClassName("org.h2.Driver");
    ds.setUrl("jdbc:h2:mem:testDB");
    ds.setUsername("sa");
    ds.setPassword("");
    HibernateConfiguration.dataSourceTest(ds);
}

@AfterClass
public static void cleanConnection(){
    HibernateConfiguration.dataSourceTest(null);
}
}

<beans xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context"
   xmlns:tx="http://www.springframework.org/schema/tx" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
    http://www.springframework.org/schema/context
    http://www.springframework.org/schema/context/spring-context-3.0.xsd
    http://www.springframework.org/schema/tx
    http://www.springframework.org/schema/tx/spring-tx-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd">

<bean id="entityManagerFactory"
      class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
    <property name="persistenceXmlLocation" value="classpath:persistence.xml" />
    <property name="persistenceUnitName" value="testingSetup" />
    <property name="dataSource" ref="dataSource" />
    <property name="jpaVendorAdapter">
        <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"/>
    </property>
</bean>

<context:component-scan base-package="com.adistec" />
<context:annotation-config/>

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
         version="2.0">
<persistence-unit name="testingSetup" transaction-type="RESOURCE_LOCAL">
    <provider>org.hibernate.ejb.HibernatePersistence</provider>
    <properties>
        <property name="hibernate.connection.driver_class" value="org.h2.Driver" />
        <property name="hibernate.connection.url" value="jdbc:h2:mem:testDB;DB_CLOSE_DELAY=-1;MODE=MySQL" />
        <property name="hibernate.connection.username" value="sa" />
        <property name="hibernate.connection.password" value="" />
        <property name="hibernate.dialect" value="org.hibernate.dialect.H2Dialect" />
        <property name="hibernate.archive.autodetection" value="class, hbm"/>
        <property name="hibernate.show_sql" value="false"/>
        <property name="hibernate.hbm2ddl.auto" value="create"/>
    </properties>
</persistence-unit>

@Entity
public class MailConfig {
  @Id
  @GeneratedValue(strategy = GenerationType.IDENTITY)
  Long id;
  @Column
  String host;
}