<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE hibernate-mapping 
    PUBLIC "-//Hibernate/Hibernate Mapping DTD//EN" 
    "http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">

<hibernate-mapping> 
 <class name="com.candidjava.hibernate.Book" table="Book_Sub">
     <id name="id"  type="int" column="id">
       <generator class="increment"/>
     </id>
		<property name="title" type="string" column="title"/>
        <property name="author"  type="string" column="author"/>
		<property name="cost"  type="double" column="cost"/>

  <joined-subclass name="com.candidjava.hibernate.SpecialEditionBook"  table="Special_Sub">
    <key column="id"/>
    <property name="newfeatures" type="string" column="features"/>
  </joined-subclass>

  <joined-subclass name="com.candidjava.hibernate.InternationalBook"   table="International_sub">
    <key column="id"/>
    <property name="languages" type="string" column="languages"/>
    <property name="region" type="int" column="region"/>
  </joined-subclass>

  </class>
</hibernate-mapping>

public Book getBook(int id) {
		Book sd = null;
		try {
			Session s = getSession();

			sd = (Book) s.get(Book.class, id);

		} catch (HibernateException e) {
			System.out.println(e.getMessage());
		}
		return sd;
	}

BookDao ms=new BookDao();
		
		Book b=ms.getBook(2);
		
		System.out.println(b.getAuthor());
		System.out.println(b.getTitle());
		System.out.println(b.getCost());
		
		if(b instanceof InternationalBook)
		{
			InternationalBook ib=(InternationalBook) b;
			System.out.println(ib.getLanguages());
			System.out.println(ib.getRegion());
		}
		if(b instanceof SpecialEditionBook)
		{
			SpecialEditionBook sb=(SpecialEditionBook) b;
			System.out.println(sb.getNewfeatures());
			
		}

package com.candidjava.hibernate;

public class Book {
	int id;
	String title;
	String author;

	double cost;

	public Book() {
	}

	public Book(String title, String author, double cost) {
		this.title = title;
		this.author = author;

		this.cost = cost;
	}

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

	public int getId() {
		return id;
	}

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

	public String getTitle() {
		return title;
	}

	public void setAuthor(String author) {
		this.author = author;
	}

	public String getAuthor() {
		return author;
	}

	public void setCost(double cost) {
		this.cost = cost;
	}

	public double getCost() {
		return cost;
	}
}

package com.candidjava.hibernate;

public class InternationalBook extends Book {

	private String languages;
	private int region;

	public InternationalBook() {
	}

	public InternationalBook(String title, String author, double cost,
			String language, int region) {
		super(title, author, cost);

		languages = language;
		this.region = region;
	}

	public void setLanguages(String s) {
		languages = s;
	}

	public String getLanguages() {
		return languages;
	}

	public void setRegion(int i) {
		region = i;
	}

	public int getRegion() {
		return region;
	}
}

package com.candidjava.hibernate;

public class SpecialEditionBook extends Book {

	private String newfeatures;

	public SpecialEditionBook() {
	}

	public SpecialEditionBook(String title, String author, double cost,
			String features) {
		super(title, author, cost);

		newfeatures = features;
	}

	public void setNewfeatures(String s) {
		newfeatures = s;
	}

	public String getNewfeatures() {
		return newfeatures;
	}
}

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