/** Implements the getter for + cards : Set(CustomerCard)
    */
   @OneToMany(targetEntity=CustomerCard.class, cascade=CascadeType.ALL,
         mappedBy ="owner" , fetch = FetchType.EAGER)
   public Set getCards() {
      if ( f_cards != null ) {
//         return Collections.unmodifiableSet(f_cards);
         return this.f_cards;
      } else {
         return null;
      }
   }
   

/** Implements the getter for owner customer
    */
   @ManyToOne(cascade=CascadeType.ALL , fetch = FetchType.EAGER)
   @JoinColumn(name="CUSTOMER_ID", nullable=false)
   public Customer getOwner() {
      return f_owner;
   }

org.hibernate.PropertyAccessException: exception setting property value with CGLIB (set hibernate.cglib.use_reflection_optimizer=false for more info) setter of example.Customer.setCards
   at org.hibernate.tuple.PojoEntityTuplizer.setPropertyValuesWithOptimizer(PojoEntityTuplizer.java:215)
   at org.hibernate.tuple.PojoEntityTuplizer.setPropertyValues(PojoEntityTuplizer.java:185)
   at org.hibernate.persister.entity.AbstractEntityPersister.setPropertyValues(AbstractEntityPersister.java:3231)
   at org.hibernate.engine.TwoPhaseLoad.initializeEntity(TwoPhaseLoad.java:126)
   at org.hibernate.loader.Loader.initializeEntitiesAndCollections(Loader.java:842)
   at org.hibernate.loader.Loader.doQuery(Loader.java:717)
   at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:223)
   at org.hibernate.loader.Loader.loadEntity(Loader.java:1782)
   at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:93)
   at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:81)
   at org.hibernate.persister.entity.AbstractEntityPersister.load(AbstractEntityPersister.java:2729)
   at org.hibernate.event.def.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:365)
   at org.hibernate.event.def.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:346)
   at org.hibernate.event.def.DefaultLoadEventListener.load(DefaultLoadEventListener.java:123)
   at org.hibernate.event.def.DefaultLoadEventListener.proxyOrLoad(DefaultLoadEventListener.java:177)
   at org.hibernate.event.def.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:87)
   at org.hibernate.impl.SessionImpl.fireLoad(SessionImpl.java:809)
   at org.hibernate.impl.SessionImpl.get(SessionImpl.java:749)
   at org.hibernate.impl.SessionImpl.get(SessionImpl.java:742)
   at org.hibernate.ejb.AbstractEntityManagerImpl.find(AbstractEntityManagerImpl.java:105)
   at bussiness.Business.showAllCustomers(Business.java:140)
   at bussiness.Business.printMenuProcess(Business.java:117)
   at bussiness.Business.main(Business.java:56)
Caused by: net.sf.cglib.beans.BulkBeanException: illegal access to loading collection
   at example.Customer$$BulkBeanByCGLIB$$e917e276.setPropertyValues(<generated>)
   at org.hibernate.tuple.PojoEntityTuplizer.setPropertyValuesWithOptimizer(PojoEntityTuplizer.java:212)
   ... 22 more
Caused by: org.hibernate.LazyInitializationException: illegal access to loading collection
   at org.hibernate.collection.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:341)
   at org.hibernate.collection.AbstractPersistentCollection.read(AbstractPersistentCollection.java:86)
   at org.hibernate.collection.PersistentSet.iterator(PersistentSet.java:138)
   at example.Customer.setCards(Customer.java:109)
   ... 24 more

<?xml version="1.0" encoding="UTF-8"?>
<entity-manager>
    <name>context</name>
    <class>example.Customer</class>
    <class>example.CustomerCard</class>


    <properties>
        <property name="hibernate.connection.url" value="jdbc:mysql://localhost:3306/onetomany"/>
        <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>
        <property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver"/>
        <property name="hibernate.connection.password" value=""/>
        <property name="hibernate.connection.username" value="Xinhua"/>
        <property name="hibernate.cglib.use_reflection_optimizer" value= "false"/>

    </properties>
</entity-manager>