package ir.khorasancustoms.g2g.persistance;

public class User {
  // <editor-fold defaultstate="collapsed" desc="FIELDS"> 
  private long id;
  private String username;
  private String password;
  private String email;
  private String telNo;
  private String mobileNo;
  private String firstName;
  private String lastName;
  private UserGroup group;
  // </editor-fold>
 
  // <editor-fold defaultstate="collapsed" desc="CONSTRUCTORS"> 
  public User() {
  }

  public User(long id, String username, String password) {
    this.id = id;
    this.username = username;
    this.password = password;
  }

  public User(String username, String password) {
    this.username = username;
    this.password = password;
  }
  // </editor-fold>
 
  // <editor-fold defaultstate="collapsed" desc="GETTERS & SETTERS"> 
  public String getEmail() {
    return email;
  }

  public void setEmail(String email) {
    this.email = email;
  }

  public String getFirstName() {
    return firstName;
  }

  public void setFirstName(String firstName) {
    this.firstName = firstName;
  }

  public UserGroup getGroup() {
    return group;
  }

  public void setGroup(UserGroup group) {
    this.group = group;
  }

  public long getId() {
    return id;
  }

  public void setId(long id) {
    this.id = id;
  }

  public String getLastName() {
    return lastName;
  }

  public void setLastName(String lastName) {
    this.lastName = lastName;
  }

  public String getMobileNo() {
    return mobileNo;
  }

  public void setMobileNo(String mobileNo) {
    this.mobileNo = mobileNo;
  }

  public String getPassword() {
    return password;
  }

  public void setPassword(String password) {
    this.password = password;
  }

  public String getTelNo() {
    return telNo;
  }

  public void setTelNo(String telNo) {
    this.telNo = telNo;
  }

  public String getUsername() {
    return username;
  }

  public void setUsername(String username) {
    this.username = username;
  }   
  // </editor-fold>
}

package ir.khorasancustoms.g2g.persistance;

import java.util.HashSet;
import java.util.Set;

public class UserGroup {
  // <editor-fold defaultstate="collapsed" desc="FIELDS">
  private long id;
  private String title;
  private String description;
  private Set<User> users = new HashSet<User>();
  // </editor-fold>

  // <editor-fold defaultstate="collapsed" desc="CONSTRUCTORS">
  public UserGroup() {
  }

  public UserGroup(String title) {
    this.title = title;
  }

  public UserGroup(long id, String title) {
    this.id = id;
    this.title = title;
  }

  public UserGroup(String title, String description) {
    this.title = title;
    this.description = description;
  }

  public UserGroup(long id, String title, String description) {
    this.id = id;
    this.title = title;
    this.description = description;
  }
  // </editor-fold>

  // <editor-fold defaultstate="collapsed" desc="GETTERS & SETTERS">
  public long getId() {
    return id;
  }

  public void setId(long id) {
    this.id = id;
  }

  public String getDescription() {
    return description;
  }

  public void setDescription(String description) {
    this.description = description;
  }

  public String getTitle() {
    return title;
  }

  public void setTitle(String title) {
    this.title = title;
  }

  public Set<User> getUsers() {
    return users;
  }

  public void setUsers(Set<User> users) {
    this.users = users;
  }   
  // </editor-fold>
}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
  <class name="ir.khorasancustoms.g2g.persistance.User" table="TBL_USER">
    <id column="USR_ID" type="big_integer" name="id">
      <generator class="sequence"/>     
    </id>
    <property name="username" type="string" column="USERNAME" length="50"/>
    <property name="password" type="string" column="PASSWORD" length="200"/>
    <property name="email" type="string" column="EMAIL" length="200"/>
    <property name="telNo" type="string" column="TEL_NUM" length="50"/>
    <property name="mobileNo" type="string" column="MOB_NUM" length="50"/>
    <property name="firstName" type="string" column="FIRST_NAME" length="50"/>
    <property name="lastName" type="string" column="LAST_NAME" length="50"/>
    <many-to-one name="group" column="UGP_ID" not-null="true" class="UserGroup"/>
  </class> 
</hibernate-mapping>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
  <class name="ir.khorasancustoms.g2g.persistance.UserGroup" table="TBL_USER_GROUP">
    <id column="UGP_ID" name="id" type="big_integer">
      <generator class="sequence"/>
    </id>
    <property column="GROUP_TITLE" length="50" name="title" type="string"/>
    <property column="GROUP_DESC" length="250" name="description" type="string"/>
    <set name="users">
      <key column="UGP_ID" not-null="true"/>
      <one-to-many class="User"/>
    </set>
  </class>
</hibernate-mapping>

import ir.khorasancustoms.g2g.persistance.UserGroup;
import org.hibernate.Session;
import org.hibernate.SessionFactory;

public class Test {
  public static void main(String[] args) {   
    SessionFactory factory = HibUtil.getSessionFactory();
    Session session = factory.getCurrentSession();
    session.beginTransaction();
   
    UserGroup userGroup = (UserGroup) session.load(UserGroup.class, 1);
   
    session.getTransaction();
    session.close();
  }
}