One to many relationship in hibernate

Question

I am very much new to hibernate,
for testing purpose I am using JPA annotations and hibernate.
While testing one to many relationship , I got a problem
I have a PurchaseOrder class and OrderLine class having one to many relationship.
package orderpackage;
import java.util.ArrayList;
import java.util.List;
import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToMany;
@Entity
public class PurchaseOrder {
  @Id
  @GeneratedValue(strategy=GenerationType.AUTO)
  private int id;
  @OneToMany(cascade=CascadeType.ALL,mappedBy="order")
  private List <OrderLine> orderLine = new ArrayList<OrderLine>();
  public PurchaseOrder(String orderName) {
  this.orderName = orderName;
  public List<OrderLine> getOrderLine() {
  return orderLine;
  public void setOrderLine(List<OrderLine> orderLine) {
  this.orderLine = orderLine;
  private String orderName;
  public int getId() {
  return id;
  public void setId(int id) {
  this.id = id;
  public String getOrderName() {
  return orderName;
  public void setOrderName(String orderName) {
  this.orderName = orderName;
OrderLine.java
package orderpackage;
import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
@Entity
public class OrderLine {
  @Id
  @GeneratedValue(strategy=GenerationType.AUTO)
  private int id;
  private String itemName;
  private int qty;
  @ManyToOne(cascade=CascadeType.ALL)
  private PurchaseOrder order;
  public OrderLine(String itemName, int qty) {
  this.itemName = itemName;
  this.qty = qty;
  public PurchaseOrder getOrder() {
  return order;
  public void setOrder(PurchaseOrder order) {
  this.order = order;
  public int getId() {
  return id;
  public void setId(int id) {
  this.id = id;
  public String getItemName() {
  return itemName;
  public void setItemName(String itemName) {
  this.itemName = itemName;
  public int getQty() {
  return qty;
  public void setQty(int qty) {
  this.qty = qty;
     OrderTest.java
package orderpackage;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
public class OrderTest {
  public static void main(String[] args) {
  PurchaseOrder order = new PurchaseOrder("order no 1");
  OrderLine orderLine1 = new OrderLine("item1",25);
  OrderLine orderLine2 = new OrderLine("item2",28);
  OrderLine orderLine3 = new OrderLine("item3",38);
  OrderLine orderLine4 = new OrderLine("item4",48);
  order.getOrderLine().add(orderLine1);
  order.getOrderLine().add(orderLine2);
  order.getOrderLine().add(orderLine3);
  order.getOrderLine().add(orderLine4);
  SessionFactory sessionFactory = new Configuration().configure().buildSessionFactory();
  Session session = sessionFactory.openSession();
  session.beginTransaction();
  session.persist(order);
  session.getTransaction().commit();
  session.close();
I can see Order and Order Line are get persisted but Order Line table don't have order_id populated automatically. Please help me out.

Answer 1

That is because you're not setting it, obviously. Nowhere in your code are you actually populating the order property of the orderlines.