Hibernate Fetching Update (#607)

* BAEL-212
Contains:
1. Hibernate Criteria Query Classes
2. Hibernate Criteria Query Test

* Updating the config file and the HibernateUtil class

* Hibernate Criteria Queries Example

* Hibernate Fetching : Eager Loading vs Lazy Loading

* Hibernate Criteria Query files

* Hibernate Eager Loading and Lazy Loading Changes

* Latest Changes on Fetching

* Fetching Changes

* Latest Changes

* Latest Changes

* Undoing the changes

core-java-8/src/test/java/com/baeldung/completablefuture/CompletableFutureTest.java

@@ -206,4 +206,4 @@ public class CompletableFutureTest {
 
     }
 
-}
+}

spring-hibernate4/src/main/java/com/baeldung/hibernate/fetching/model/OrderDetail.java

@@ -3,80 +3,71 @@ package com.baeldung.hibernate.fetching.model;
 import java.io.Serializable;
 import java.sql.Date;
 
-public class OrderDetail implements Serializable {
+public class OrderDetail implements Serializable{
-
-    private static final long serialVersionUID = 1L;
-    private Long orderId;
-    private Date orderDate;
-    private String orderDesc;
-    private User user;
-
-    public OrderDetail() {
-
-    }
-
-    public OrderDetail(Date orderDate, String orderDesc) {
-        super();
-        this.orderDate = orderDate;
-        this.orderDesc = orderDesc;
-    }
-
-    public Date getOrderDate() {
-        return orderDate;
-    }
-
-    public void setOrderDate(Date orderDate) {
-        this.orderDate = orderDate;
-    }
-
-    public String getOrderDesc() {
-        return orderDesc;
-    }
-
-    public void setOrderDesc(String orderDesc) {
-        this.orderDesc = orderDesc;
-    }
-
-    public User getUser() {
-        return user;
-    }
-
-    public void setUser(User user) {
-        this.user = user;
-    }
-
-    @Override
-    public int hashCode() {
-        final int prime = 31;
-        int result = 1;
-        result = prime * result + ((orderId == null) ? 0 : orderId.hashCode());
-        return result;
-    }
-
-    @Override
-    public boolean equals(Object obj) {
-        if (this == obj)
-            return true;
-        if (obj == null)
-            return false;
-        if (getClass() != obj.getClass())
-            return false;
-        OrderDetail other = (OrderDetail) obj;
-        if (orderId == null) {
-            if (other.orderId != null)
-                return false;
-        } else if (!orderId.equals(other.orderId))
-            return false;
-
-        return true;
-    }
-
-    public Long getOrderId() {
-        return orderId;
-    }
-
-    public void setOrderId(Long orderId) {
-        this.orderId = orderId;
-    }
 
+	private static final long serialVersionUID = 1L;
+	private Long orderId;
+	private Date orderDate;
+	private String orderDesc;
+	private User user;
+	
+	public OrderDetail(){	
+	}
+		
+	public OrderDetail(Date orderDate, String orderDesc) {
+		super();
+		this.orderDate = orderDate;
+		this.orderDesc = orderDesc;
+	}
+	
+	public Date getOrderDate() {
+		return orderDate;
+	}
+	public void setOrderDate(Date orderDate) {
+		this.orderDate = orderDate;
+	}
+	public String getOrderDesc() {
+		return orderDesc;
+	}
+	public void setOrderDesc(String orderDesc) {
+		this.orderDesc = orderDesc;
+	}
+	public User getUser() {
+		return user;
+	}
+	public void setUser(User user) {
+		this.user = user;
+	}
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		result = prime * result + ((orderId == null) ? 0 : orderId.hashCode());
+		return result;
+	}
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj)
+			return true;
+		if (obj == null)
+			return false;
+		if (getClass() != obj.getClass())
+			return false;
+		OrderDetail other = (OrderDetail) obj;
+		if (orderId == null) {
+			if (other.orderId != null)
+				return false;
+		} else if (!orderId.equals(other.orderId))
+			return false;
+		
+		return true;
+	}
+	public Long getOrderId() {
+		return orderId;
+	}
+	public void setOrderId(Long orderId) {
+		this.orderId = orderId;
+	}
 }
+
+

spring-hibernate4/src/main/java/com/baeldung/hibernate/fetching/model/User.java

@@ -17,12 +17,11 @@ public class User implements Serializable {
     }
 
     public User(final Long userId, final String userName, final String firstName, final String lastName) {
-        super();
+	super();
-        this.userId = userId;
+	this.userId = userId;
-        this.userName = userName;
+	this.userName = userName;
-        this.firstName = firstName;
+	this.firstName = firstName;
-        this.lastName = lastName;
+	this.lastName = lastName;
-
     }
 
     @Override

spring-hibernate4/src/main/java/com/baeldung/hibernate/fetching/util/HibernateUtil.java

@@ -1,24 +1,27 @@
 package com.baeldung.hibernate.fetching.util;
 
 import org.hibernate.Session;
+import org.hibernate.SessionFactory;
 import org.hibernate.cfg.Configuration;
 
 public class HibernateUtil {
 
-    @SuppressWarnings("deprecation")
+	@SuppressWarnings("deprecation")
-    public static Session getHibernateSession(String fetchMethod) {
+	public static Session getHibernateSession(String fetchMethod) {
-        //two config files are there
+		//two config files are there
-        //one with lazy loading enabled
+		//one with lazy loading enabled 
-        //another lazy = false
+		//another lazy = false
-
+		SessionFactory sf = null;
-        final String configFileName = "lazy".equals(fetchMethod) ?
+		if ("lazy".equals(fetchMethod)) {
-          "fetchingLazy.cfg.xml" :
+			sf = new Configuration().configure("fetchingLazy.cfg.xml").buildSessionFactory();
-          "fetching.cfg.xml";
+		} else {
-
+			sf = new Configuration().configure("fetching.cfg.xml").buildSessionFactory();
-        return new Configuration()
+		}
-          .configure(configFileName)
+		
-          .buildSessionFactory().openSession();
+		// fetching.cfg.xml is used for this example
-    }
+		final Session session = sf.openSession();
+		return session;
+	}
 
     public static Session getHibernateSession() {
         return new Configuration()

spring-hibernate4/src/main/java/com/baeldung/hibernate/fetching/view/FetchingAppView.java

@@ -18,93 +18,94 @@ import com.baeldung.hibernate.fetching.model.User;
 
 public class FetchingAppView {
 
-    public FetchingAppView() {
+	public FetchingAppView(){
+		
+	}
+	
+	//lazily loaded 
+	public Set<OrderDetail> lazyLoaded(){
+		final Session sessionLazy = HibernateUtil.getHibernateSession("lazy");
+		List<User> users = sessionLazy.createQuery("From User").list();
+		User userLazyLoaded = new User();
+		userLazyLoaded = users.get(3); 
+		//since data is lazyloaded so data won't be initialized
+		Set<OrderDetail> orderDetailSet = userLazyLoaded.getOrderDetail();
+		return (orderDetailSet);	
+	}
+	
+	//eagerly loaded
+	public Set<OrderDetail> eagerLoaded(){
+		final Session sessionEager = HibernateUtil.getHibernateSession();
+		//data should be loaded in the following line
+		//also note the queries generated
+		List<User> users =sessionEager.createQuery("From User").list();
+		User userEagerLoaded = new User();
+		userEagerLoaded = users.get(3); 
+		Set<OrderDetail> orderDetailSet = userEagerLoaded.getOrderDetail();
+		return orderDetailSet;	
+	}
+	
+	
+	//creates test data
+	//call this method to create the data in the database
+	public void createTestData() {
 
-    }
+		final Session session = HibernateUtil.getHibernateSession();
+		Transaction tx = null;
+		tx = session.beginTransaction();
+		final User user1 = new User();
+		final User user2 = new User();
+		final User user3 = new User();
+				
+		user1.setFirstName("Priyam");
+		user1.setLastName("Banerjee");
+		user1.setUserName("priyambanerjee");
+		session.save(user1);
+		
+		user2.setFirstName("Navneeta");
+		user2.setLastName("Mukherjee");
+		user2.setUserName("nmukh");
+		session.save(user2);
+		
+		user3.setFirstName("Molly");
+		user3.setLastName("Banerjee");
+		user3.setUserName("mollyb");
+		session.save(user3);
 
-    public boolean lazyLoaded() {
+		final OrderDetail order1 = new OrderDetail();
-        final Session sessionLazy = HibernateUtil.getHibernateSession("lazy");
+		final OrderDetail order2 = new OrderDetail();
-        List<User> users = sessionLazy.createQuery("From User").list();
+		final OrderDetail order3 = new OrderDetail();
-        User userLazyLoaded = users.get(3);
+		final OrderDetail order4 = new OrderDetail();
-        //since data is lazyloaded so data won't be initialized
+		final OrderDetail order5 = new OrderDetail();
-        Set<OrderDetail> orderDetailSet = userLazyLoaded.getOrderDetail();
 
-        return (Hibernate.isInitialized(orderDetailSet));
+		order1.setOrderDesc("First Order");
-    }
+		order1.setOrderDate(new Date(2014, 10, 12));
+		order1.setUser(user1);
+		
+		order2.setOrderDesc("Second Order");
+		order2.setOrderDate(new Date(2016, 10, 25));
+		order2.setUser(user1);
+		
+		order3.setOrderDesc("Third Order");
+		order3.setOrderDate(new Date(2015, 2, 17));
+		order3.setUser(user2);
+		
+		order4.setOrderDesc("Fourth Order");
+		order4.setOrderDate(new Date(2014, 10, 1));
+		order4.setUser(user2);
+		
+		order5.setOrderDesc("Fifth Order");
+		order5.setOrderDate(new Date(2014, 9, 11));
+		order5.setUser(user3);
+		
+		session.saveOrUpdate(order1);
+		session.saveOrUpdate(order2);
+		session.saveOrUpdate(order3);
+		session.saveOrUpdate(order4);
+		session.saveOrUpdate(order5);
 
-    public boolean eagerLoaded() {
+		tx.commit();
-        final Session sessionEager = HibernateUtil.getHibernateSession();
+		session.close();
-        //data should be loaded in the following line
-        //also note the queries generated
-        List<User> users = sessionEager.createQuery("From User").list();
-        User userEagerLoaded = users.get(3);
-        Set<OrderDetail> orderDetailSet = userEagerLoaded.getOrderDetail();
 
-        return (Hibernate.isInitialized(orderDetailSet));
+	}
-    }
-
-
-    //creates test data
-    //call this method to create the data in the database
-    public void createTestData() {
-
-        final Session session = HibernateUtil.getHibernateSession();
-        Transaction tx = session.beginTransaction();
-
-        final User user1 = new User();
-        final User user2 = new User();
-        final User user3 = new User();
-
-        user1.setFirstName("Priyam");
-        user1.setLastName("Banerjee");
-        user1.setUserName("priyambanerjee");
-        session.save(user1);
-
-        user2.setFirstName("Navneeta");
-        user2.setLastName("Mukherjee");
-        user2.setUserName("nmukh");
-        session.save(user2);
-
-        user3.setFirstName("Molly");
-        user3.setLastName("Banerjee");
-        user3.setUserName("mollyb");
-        session.save(user3);
-
-        final OrderDetail order1 = new OrderDetail();
-        final OrderDetail order2 = new OrderDetail();
-        final OrderDetail order3 = new OrderDetail();
-        final OrderDetail order4 = new OrderDetail();
-        final OrderDetail order5 = new OrderDetail();
-
-        order1.setOrderDesc("First Order");
-        order1.setOrderDate(new Date(2014, 10, 12));
-        order1.setUser(user1);
-
-        order2.setOrderDesc("Second Order");
-        order2.setOrderDate(new Date(2016, 10, 25));
-        order2.setUser(user1);
-
-        order3.setOrderDesc("Third Order");
-        order3.setOrderDate(new Date(2015, 2, 17));
-        order3.setUser(user2);
-
-        order4.setOrderDesc("Fourth Order");
-        order4.setOrderDate(new Date(2014, 10, 1));
-        order4.setUser(user2);
-
-        order5.setOrderDesc("Fifth Order");
-        order5.setOrderDate(new Date(2014, 9, 11));
-        order5.setUser(user3);
-
-
-        session.saveOrUpdate(order1);
-        session.saveOrUpdate(order2);
-        session.saveOrUpdate(order3);
-        session.saveOrUpdate(order4);
-        session.saveOrUpdate(order5);
-
-        // session.saveOrUpdate(user1);
-        tx.commit();
-        session.close();
-    }
 }

spring-hibernate4/src/test/java/com/baeldung/hibernate/fetching/HibernateFetchingTest.java

@@ -1,24 +1,43 @@
 package com.baeldung.hibernate.fetching;
 
 import static org.junit.Assert.*;
+import java.util.Set;
 
+import org.hibernate.Hibernate;
+import org.junit.Before;
 import org.junit.Test;
 
+import com.baeldung.hibernate.fetching.model.OrderDetail;
+
 import com.baeldung.hibernate.fetching.view.FetchingAppView;
 
 public class HibernateFetchingTest {
 
+
+	//this loads sample data in the database
+	@Before 
+	public void addFecthingTestData(){
+		FetchingAppView fav = new FetchingAppView();
+		fav.createTestData();
+	}
+	
+	//testLazyFetching() tests the lazy loading
+	//Since it lazily loaded so orderDetalSetLazy won't
+	//be initialized
 	@Test
 	public void testLazyFetching() {
 		FetchingAppView fav = new FetchingAppView();
-		fav.createTestData();
+		Set<OrderDetail> orderDetalSetLazy = fav.lazyLoaded();
-		assertFalse(fav.lazyLoaded());
+		assertFalse(Hibernate.isInitialized(orderDetalSetLazy));
 	}
-
+	
+	//testEagerFetching() tests the eager loading
+	//Since it eagerly loaded so orderDetalSetLazy would
+	//be initialized
 	@Test
 	public void testEagerFetching() {
 		FetchingAppView fav = new FetchingAppView();
-		assertTrue(fav.eagerLoaded());
+		Set<OrderDetail> orderDetalSetEager = fav.eagerLoaded();
+		assertTrue(Hibernate.isInitialized(orderDetalSetEager));
 	}
-
 }