org.hibernate.QueryException: The collection was unreferenced - spring

Question

Please find the java class xml files.
package com.example;
import java.util.List;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class TestHibernateFilter {
#SuppressWarnings("unchecked")
public static void main(String... strings) {
ApplicationContext context = new ClassPathXmlApplicationContext("sravan.xml");
SessionFactory factory = context.getBean(SessionFactory.class);
Session session = factory.openSession();
Family family = (Family)session.get(Family.class, 1);
//Set<Person> persons = family.getMembers();
//System.out.println("persons "+persons);
List<Person> entityList = session.createFilter(family.getMembers(), "where id > :id").setInteger("id", 0).list();
List<String> entityNames = session.createFilter(entityList, "select firstName").list();
System.out.println("names are "+entityNames);
}
}
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mongo="http://www.springframework.org/schema/data/mongo"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/data/mongo http://www.springframework.org/schema/data/mongo/spring-mongo-1.2.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<tx:annotation-driven transaction-manager="transactionManager"/>
<context:annotation-config />
<context:component-scan base-package="com.example" />
<bean id="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory"></property>
</bean>
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.p6spy.engine.spy.P6SpyDriver" />
<property name="url" value="jdbc:mysql://localhost/sravan"/>
<property name="username" value="root" />
<property name="password" value="root" />
</bean>
<bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="packagesToScan" value="com.example"></property>
<property name="dataSource" ref="dataSource"></property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.current_session_context_class">thread</prop>
<prop key="show_sql">true</prop>
<prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>
<prop key="hibernate.hbm2ddl.auto">update</prop>
</props>
</property>
</bean>
</beans>
if i run main method am getting org.hibernate.QueryException: The collection was unreferenced exception. am i missing any configuration?? and explain me about exception