Generic DAO layer and configuration of Transaction Manager, SessionFactory in Hibernate for PostgreSQL

AbstractDao.java

package com.bytestree.dao;

import java.io.Serializable;
import java.lang.reflect.ParameterizedType;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;

@SuppressWarnings("unchecked")
public abstract class AbstractDao<E> implements EntityDao<E> {

	private final Class<E> entityClass;

	public AbstractDao() {
		this.entityClass = (Class<E>) ((ParameterizedType) this.getClass().getGenericSuperclass())
				.getActualTypeArguments()[0];
	}
	
	@Autowired
	private SessionFactory sessionFactory;

	protected Session getSession() {
		return this.sessionFactory.getCurrentSession();
	}

	@Override
	public E findById(final Serializable id) {
		return (E) getSession().get(entityClass, id);
	}

	@Override
	public void save(E entity) {
		getSession().saveOrUpdate(entity);
	}
	 
}

dao-context.xml

<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"
	xsi:schemaLocation="
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.2.xsd">


	<tx:annotation-driven transaction-manager="txManager" />

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

	<bean id="sessionFactory"
		class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
		<property name="hibernateProperties">
			<props>
				<prop key="hibernate.dialect">${hibernate.dialect}</prop>
				<prop key="hibernate.show_sql">${hibernate.showsql}</prop>
				<prop key="hibernate.jdbc.batch_size">${hibernate.batch.size}</prop>
			</props>
		</property>
		<property name="dataSource" ref="dataSource" />
		<property name="packagesToScan">
			<list>
				<value>com.bytestree.model</value>
			</list>
		</property>
	</bean>

	<bean id="dataSource"
		class="org.springframework.jdbc.datasource.DriverManagerDataSource">
		<property name="driverClassName" value="${datasource.driver}" />
		<property name="url" value="${datasource.url}" />
		<property name="username" value="${datasource.username}" />
		<property name="password" value="${datasource.password}" />
	</bean>
</beans>

UserDaoImpl.java

package com.bytestree.dao;

import org.springframework.stereotype.Repository;

import com.bytestree.model.Users;

@Repository("userDao")
public class UserDaoImpl extends AbstractDao<Users> implements UserDao {


}

Refer Spring Security 4 with Hibernate for complete example.