Using HSQL database with Hibernate

Step-1

Add dependency inside the pom.xml

<!-- Dependency for hibernate -->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>4.2.4.Final</version>
        </dependency>

        <!-- Dependency for HSQL Database -->
        <dependency>
            <groupId>org.hsqldb</groupId>
            <artifactId>hsqldb</artifactId>
            <version>2.2.9</version>
        </dependency>
    </dependencies>



Step-2

<!-- Hibernate 4 with spring 3.x -->
    <bean id="librarySessionFactory"
        class="org.springframework.orm.hibernate4.LocalSessionFactoryBean" scope="singleton">
        <property name="dataSource" ref="libraryDataSource" />
        <property name="packagesToScan">
            <list>
                <value>com.usc.dao.entity</value>
            </list>
        </property>
        <property name="hibernateProperties">
            <props>
                 <prop key="hibernate.dialect">org.hibernate.dialect.HSQLDialect</prop>
                <prop key="hibernate.show_sql">true</prop>
                <!-- below key is important use this key = hibernate.hbm2ddl.auto not
                    hbm2ddl.auto -->
                <prop key="hibernate.generate_statistics">true</prop>
                <prop key="hibernate.hbm2ddl.auto">update</prop>
            </props>
        </property>
    </bean>


Step-3
Define the datasource



<context:property-placeholder location="/WEB-INF/context/persistence-mysql.properties" /> 
    <bean id="libraryDataSource"
        class="org.springframework.jdbc.datasource.DriverManagerDataSource" scope="singleton">
        <property name="driverClassName" value="${db.driverclassname}" />
        <property name="url" value="${db.url}" />
        <property name="username" value="${db.username}" />
        <property name="password" value="${db.password}" />
    </bean>

Step-4
"/WEB-INF/context/persistence-mysql.properties

################Comment###############
#db.driverclassname=com.mysql.jdbc.Driver
#db.url=jdbc:mysql://localhost:3306/library_db?createDatabaseIfNotExist=true
#db.username=root
#db.password=root
########Setting for HSQL##################
db.driverclassname=org.hsqldb.jdbc.JDBCDriver
db.url=jdbc:hsqldb:mem:library_db?createDatabaseIfNotExist=true
db.username=sa
db.password=
 

Step-5
Define Spring Transaction Manager

<!--
       @Transactional
     -->
    <tx:annotation-driven proxy-target-class="true"
        transaction-manager="transactionManager" />

    <bean id="transactionManager"
        class="org.springframework.orm.hibernate4.HibernateTransactionManager">
        <property name="sessionFactory" ref="librarySessionFactory"></property>
    </bean> 


Step-6
Applying transaction manager in dao layer 

/**
 *
 * @author usc
 *
 */
@Repository("IUserDao")
@Transactional(propagation=Propagation.REQUIRED)
public class IUserDao  extends AbstractDaoImpl<UserEntity,Integer> implements UserDao {

}


AbstractDaoImpl.java

/**
 * @author usc
 * @param <E>
 * @param <I>
 */
public abstract class AbstractDaoImpl<E, I extends Serializable> implements AbstractDao<E, I> {

    private Class<E> entityClass;

    protected AbstractDaoImpl(Class<E> entityClass) {
        this.entityClass = entityClass;
    }

    @Autowired
    @Qualifier("librarySessionFactory")
    private SessionFactory psessionFactory;

    public Session getCurrentSession() {
        return psessionFactory.getCurrentSession();
    }
}