List Collection componets based object mapping in Hibernate 4.x

In Hibernate you can also map a collection of component based objects by making object Embeddable  . like in following example we have Product and one product can have multiple image and image can have further its attribute like image name ,width length . so we put all image object in collection and map to it a single product object .

here we have

Product.java

package in.jk.list.component.maping;

import java.util.List;

 

import javax.persistence.CollectionTable;

import javax.persistence.ElementCollection;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.OrderColumn;
import javax.persistence.Table;

@Entity

@Table(name="Products")

public class Product {

 

@Id

 

private int productId;

private String productName;
private String price;

@ElementCollection
@CollectionTable(name="Prodcut_Images")
@OrderColumn(name="product_image_index")
private List<ProductImage> productImageList;

public int getProductId() {
return productId;
}

public void setProductId(int productId) {

this.productId = productId;

}

public String getProductName() {

return productName;
}

public void setProductName(String productName) {

this.productName = productName;
}

public String getPrice() {

return price;
}

public void setPrice(String price) {

this.price = price;
}

public List<ProductImage> getProductImageList() {

return productImageList;
}

public void setProductImageList(List<ProductImage> productImageList) {

this.productImageList = productImageList;

}
}


ProductImage.java

package in.jk.list.component.maping;

import javax.persistence.Embeddable;

 

@Embeddable

public class ProductImage {

 

private String imageName;

private int length;
private int width;

public String getImageName() {
return imageName;
}

public void setImageName(String imageName) {

this.imageName = imageName;
}

public int getLength() {

eturn length;
}

public void setLength(int length) {

this.length = length;

}

public int getWidth() {

return width;
}

public void setWidth(int width) {

this.width = width;


}
}

Hibernate.cfg.xml

<?xml version = "1.0" encoding = "utf-8"?>

<!DOCTYPE hibernate-configuration SYSTEM

"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>

<session-factory>

<property name="hibernate.show_sql">true</property>

<property name="hbm2ddl.auto">update</property>
<property name="hibernate.dialect">org.hibernate.dialect.ProgressDialect</property>
<property name="hibernate.connection.driver_class">org.postgresql.Driver</property>
<!-- Assume hibernate is the database name -->

<property name="hibernate.connection.url">jdbc:postgresql://localhost/hibernate</property>

<property name="hibernate.connection.username">postgres</property>
<property name="hibernate.connection.password">postgres</property>
<mapping class="in.jk.list.component.maping.Product" />

</session-factory>

</hibernate-configuration>

 

HibernateTest .java

package in.jk.list.component.maping;

 

import java.util.ArrayList;

import java.util.List;

import org.hibernate.Session;

import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;

public class HibernateTest {

public static void main(String[] args) {

Configuration configuration = new Configuration();configuration.configure("hibernate.cfg.xml")

ServiceRegistry serviceRegistry = new ServiceRegistryBuilder().applySettings(configuration.getProperties())

.buildServiceRegistry();

SessionFactory sessionFactory = configuration.buildSessionFactory(serviceRegistry);

 

Session session = sessionFactory.openSession();

Transaction transaction = session.beginTransaction();


 

Product product1 = new Product();

product1.setProductId(1);

product1.setProductName("Mobile");
product1.setPrice("20000");

ProductImage productImage1 = new ProductImage();

productImage1.setImageName("Mob1");

productImage1.setLength(12);
productImage1.setWidth(58);

ProductImage productImage2 = new ProductImage();

 

productImage2.setImageName("Mob2");

productImage2.setLength(18);
productImage2.setWidth(48);

ProductImage productImage3 = new ProductImage();

productImage3.setImageName("Mob3");

productImage3.setLength(23);
productImage3.setWidth(89);

List<ProductImage> imageList = new ArrayList<ProductImage>();

imageList.add(productImage1);

imageList.add(productImage2);
mageList.add(productImage3);
product1.setProductImageList(imageList);

session.persist(product1);

transaction.commit();

 

session.flush();

session.close();
System.out.println("Saved.............");
 

 

}
}
 In Database Products table data looks like this .......
 

 
 
 
Product_image table with Prodcuct Image Data