package com.foo.persist;

import java.util.Set;

public class Parent {

   private Long internalId;
   private String parentId;
   private Set<ContactIssue> contactIssueSet;
   private Integer version;
   
   public Long getInternalId() {
      return internalId;
   }
   public void setInternalId(Long internalId) {
      this.internalId = internalId;
   }
   public String getParentId() {
      return parentId;
   }
   public void setParentId(String parentId) {
      this.parentId = parentId;
   }
   
   public Integer getVersion() {
      return version;
   }
   public void setVersion(Integer version) {
      this.version = version;
   }
   public Set<ContactIssue> getContactIssueSet() {
      return contactIssueSet;
   }
   public void setContactIssueSet(Set<ContactIssue> contactIssueSet) {
      this.contactIssueSet = contactIssueSet;
   }
   
}

package com.foo.persist;

import java.io.Serializable;
import java.util.Date;

public class ContactIssue implements Serializable {

   /**
    *
    */
   private static final long serialVersionUID = 1L;

   private Contact contact;

   private Date dateTime;

   private Parent parent;

   private Integer version;

   public Contact getContact() {
      return contact;
   }

   public void setContact(Contact contact) {
      this.contact = contact;
   }

   public Date getDateTime() {
      return dateTime;
   }

   public void setDateTime(Date dateTime) {
      this.dateTime = dateTime;
   }

   public Parent getParent() {
      return parent;
   }

   public void setParent(Parent parent) {
      this.parent = parent;
   }

   public Integer getVersion() {
      return version;
   }

   public void setVersion(Integer version) {
      this.version = version;
   }

}

package com.foo.persist;

public class Contact {

   private Long internalId;

   private String name;

   private Integer version;

   public Long getInternalId() {
      return internalId;
   }

   public void setInternalId(Long internalId) {
      this.internalId = internalId;
   }

   public String getName() {
      return name;
   }

   public void setName(String name) {
      this.name = name;
   }

   public Integer getVersion() {
      return version;
   }

   public void setVersion(Integer version) {
      this.version = version;
   }

}

package com.foo.test;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.sql.SQLException;
import java.util.Date;
import java.util.HashSet;

import org.dbunit.DatabaseUnitException;
import org.hibernate.Session;
import org.hibernate.Transaction;

import com.foo.persist.Contact;
import com.foo.persist.ContactIssue;
import com.foo.persist.Parent;
import com.foo.util.HibernateSessionFactory;

public class Test {

   /**
    * @param args
    * @throws IOException
    * @throws FileNotFoundException
    * @throws SQLException
    * @throws DatabaseUnitException
    */
   @SuppressWarnings("unchecked")
   public static void main(String[] args) throws FileNotFoundException, IOException, DatabaseUnitException, SQLException {
      
      Parent lParent = new Parent();
      lParent.setParentId("PARENT1");
      HashSet<ContactIssue> lContactIssueSet = new HashSet<ContactIssue>();
      ContactIssue lContactIssue = new ContactIssue();
      Contact lContact = new Contact();
      lContact.setName("CONTACT1");
      lContactIssue.setContact(lContact);
      lContactIssue.setDateTime(new Date());
      lContactIssue.setParent(lParent);
      lContactIssueSet.add(lContactIssue);
      lParent.setContactIssueSet(lContactIssueSet);
      
      Session lSession = HibernateSessionFactory.getSession();
      Transaction t = lSession.beginTransaction();
      lSession.merge(lParent);
      t.commit();
      HibernateSessionFactory.closeSession();
   }
}

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
        "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
        "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping package="com.foo.persist">

   <class name="Parent" table="PAR_PARENT" lazy="true">
      <id column="PAR_UID" name="internalId" type="long">
         <generator class="native" />
      </id>

      <version name="version" column="PAR_VERSION" />

      <property column="PAR_ID" name="parentId" type="string"
         length="32">
      </property>

      <set name="contactIssueSet" inverse="false" cascade="all, delete-orphan">
         <key column="COI_PAR_UID"/>
         <one-to-many class="ContactIssue"/>
      </set>
      
   </class>

</hibernate-mapping>

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
        "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
        "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping package="com.foo.persist">

   <class name="ContactIssue" table="COI_CONTACT_ISSUE" lazy="true">
      <composite-id>
         <key-many-to-one
            name="contact"
            class="Contact"
         >
            <column name="COI_CON_UID" not-null="true" />
         </key-many-to-one>
         <key-property
            name="dateTime"
            type="java.util.Date"
          >
            <column name="COI_TIMESTAMP" not-null="true" />
         </key-property>
      </composite-id>
      
      <version name="version" column="COI_VERSION" />
      
      <many-to-one
         column="COI_PAR_UID"
         name="parent"
         class="Parent"      
      />

   </class>

</hibernate-mapping>

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
        "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
        "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping package="com.foo.persist">

   <class name="Contact" table="CON_CONTACT" lazy="true">
      <id column="CON_UID" name="internalId" type="long">
         <generator class="native" />
      </id>
      
      <version name="version" column="CON_VERSION" />
      
      <property name="name" column="CON_NAME" type="string" length="32"/>

   </class>

</hibernate-mapping>