<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping>
  <class name="foo.Order" table="t_order">
    <id name="orderId" column="order_id" type="int" unsaved-value="0" access="field" >
      <generator class="identity" />
    </id>
    <set name="orderLines" cascade="all-delete-orphan" access="field" inverse="true" fetch="select">
      <key column="order_id" />
      <one-to-many class="foo.OrderLine" />
    </set>
  </class>
  <class name="foo.OrderLine" table="order_line">
    <id name="lineId" column="order_line_id" type="int" unsaved-value="0" access="field" >
      <generator class="identity" />
    </id>
    <many-to-one name="order" column="order_id" class="foo.Order" />
    <property name="articleId" column="article_id" type="string" />
  </class>
</hibernate-mapping>

package foo;

import java.util.*;

public class Order {

  private int orderId;

  public int getOrderId() {
    return orderId;
  }

  private Set<OrderLine> orderLines = new HashSet<OrderLine>();

  public Set<OrderLine> getLines() {
    return Collections.unmodifiableSet(orderLines);
  }

  public void addLine(OrderLine orderLine){
    orderLine.setOrder(this);
    this.orderLines.add(orderLine);
  }
 
  public String toString() {
    return "" + getOrderId() + " - " + getLines();
  }
}

package foo;

public class OrderLine {

  private int lineId = 0;
 
  private Order order;
 
  private String articleId;

 
  public int getLineId() {
    return lineId;
  }

  public Order getOrder() {
    return order;
  } 

  public String getArticleId() {
    return articleId;
  }

  public void setOrder(Order order) {
    this.order = order;
  }

  public void setArticleId(String articleId) {
    this.articleId = articleId;
  }
 
  public String toString() {
    return "[" + getLineId() + ":" + getArticleId() + "]";
  }
}

package foo;

import org.hibernate.test.TestCase;
import org.hibernate.Session;
import org.hibernate.Criteria;
import org.hibernate.criterion.CriteriaSpecification;
import org.hibernate.criterion.Expression;
import org.hibernate.sql.JoinFragment;

import java.util.List;

public class SubcriteriaTest extends TestCase {
 
  public SubcriteriaTest(String s) {
    super(s);
  }

  protected String getBaseForMappings() {
    return "foo/";
  }

  protected String[] getMappings() {
    return new String[] { "Order.hbm.xml" };
  }

  public void testSubcriteria() {
    Session s = openSession();
    s.getTransaction().begin();
   
    // Order with one mathing line and one non-matching
    Order order = new Order();
    OrderLine line = new OrderLine();
    line.setArticleId("1000");
    order.addLine(line);
    line = new OrderLine();
    line.setArticleId("3000");
    order.addLine(line);
    s.persist(order);
   
    // Order with no lines
    order = new Order();
    s.persist(order);
   
    // Order with non-matching line
    order = new Order();
    line = new OrderLine();
    line.setArticleId("3000");
    order.addLine(line);
    s.persist(order);
   
    s.flush();
    s.clear();
   

    // Get order, to verify persist()
    order = (Order) s.get(Order.class, 1);
    assertEquals("Order 1 has 2 lines", 2, order.getLines().size());
    s.clear(); // (Removing this makes the problem disappear!!!)


    // Search orders with specified article
    List orders = findOrders(s, "3000", "3000");
    assertEquals(2, orders.size());
    order = (Order) orders.get(0);
    assertEquals("Order 1 has 2 lines", 2, order.getLines().size()); // FAILS! Only contains matching line
   

    // Search order with no lines, or 
    orders = findOrders(s, null, "1000");
    assertEquals(2, orders.size());
    order = (Order) orders.get(1);
    assertTrue("No lines on order no 2", order.getLines().isEmpty());
    order = (Order) orders.get(0);
    assertEquals("Order 1 has 2 lines", 2, order.getLines().size()); // FAILS! Only contains matching line

    s.close();
  }
 
  /**
   * Find orders by criteria in search form.
   * @param articleIdFrom Start of selection interval. If not provided, include orders
   * with no lines.
   * @param articleIdto End of selection interval.
   */
  private List findOrders(Session s, String articleIdFrom, String articleIdto) {
    Criteria criteria = s.createCriteria(Order.class);
    // criteria.setFetchMode("orderLines", FetchMode.SELECT); // Note: Does not help
    // Note: JoinFragment.LEFT_OUTER_JOIN must be used to include orders with no lines
    Criteria linesCritera = criteria.createCriteria("orderLines", JoinFragment.LEFT_OUTER_JOIN);

    /* Same result:
    criteria.createAlias("orderLines", "lines", JoinFragment.LEFT_OUTER_JOIN);
    */
   
    if(! isBlank(articleIdFrom) || ! isBlank(articleIdto)) {
      if(! isBlank(articleIdFrom)) {
        linesCritera.add(Expression.ge("articleId", articleIdFrom)); // >=
        if(! isBlank(articleIdto)) // To also
          linesCritera.add(Expression.le("articleId", articleIdto)); // <=
      }
      else if(! isBlank(articleIdto)) { // Only to
        linesCritera.add(Expression.or(
          Expression.isNull("articleId"),          // Allow null
          Expression.le("articleId", articleIdto)) // <=
        );
      }
    }
   
    criteria.setResultTransformer(CriteriaSpecification.DISTINCT_ROOT_ENTITY); // Needed b.o. left join

    return criteria.list();
   
  }
 
  private static boolean isBlank(String s) {
    return s == null || s.trim().length() == 0;
  }
}