HHH-5465 - HQL left join fetch of an element collection following a left join fetch of a one-to-one relationship causes NullPointerException (testcase)

hibernate-core/src/test/java/org/hibernate/test/collection/set/hhh8206/Contact.java

@@ -0,0 +1,97 @@
+package org.hibernate.test.collection.set.hhh8206;
+
+import java.io.Serializable;
+import java.util.HashSet;
+import java.util.Set;
+import javax.persistence.Basic;
+import javax.persistence.CollectionTable;
+import javax.persistence.ElementCollection;
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.ManyToMany;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
+
+@Entity
+@Table(name="contact")
+public class Contact implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+    private Long id;
+    private String name;
+    private Set<EmailAddress> emailAddresses = new HashSet<EmailAddress>();
+    private Set<EmailAddress> emailAddresses2 = new HashSet<EmailAddress>();
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    @Basic
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    @ElementCollection
+    @CollectionTable(name = "user_email_addresses2", joinColumns = @JoinColumn(name = "user_id", referencedColumnName = "id"))
+    public Set<EmailAddress> getEmailAddresses2() {
+        return emailAddresses2;
+    }
+
+    public void setEmailAddresses2(Set<EmailAddress> emailAddresses2) {
+        this.emailAddresses2 = emailAddresses2;
+    }
+
+    @ElementCollection
+    @CollectionTable(name = "user_email_addresses", joinColumns = @JoinColumn(name = "user_id", referencedColumnName = "id"))
+    public Set<EmailAddress> getEmailAddresses() {
+        return emailAddresses;
+    }
+
+    public void setEmailAddresses(Set<EmailAddress> emailAddresses) {
+        this.emailAddresses = emailAddresses;
+    }
+
+    @Override
+    public int hashCode() {
+        int hash = 0;
+        hash += (id != null ? id.hashCode() : 0);
+        return hash;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj == null) {
+            return false;
+        }
+        if (!(obj instanceof Contact)) {
+            return false;
+        }
+        final Contact other = (Contact) obj;
+        if (this.id == null || other.id == null) {
+            return this == obj;
+        }
+        if(!this.id.equals(other.id)) {
+            return this == obj;
+        }
+        return true;
+    }
+
+    @Override
+    public String toString() {
+        return "com.clevercure.web.hibernateissuecache.User[ id=" + id + " ]";
+    }
+}

hibernate-core/src/test/java/org/hibernate/test/collection/set/hhh8206/EmailAddress.java

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+package org.hibernate.test.collection.set.hhh8206;
+
+import java.io.Serializable;
+import java.util.Set;
+import javax.persistence.*;
+
+@Embeddable
+public class EmailAddress implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+    private String email;
+
+    public EmailAddress() {
+    }
+
+    public EmailAddress(String email) {
+        this.email = email;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+    @Override
+    public int hashCode() {
+        int hash = 0;
+        hash += (email != null ? email.hashCode() : 0);
+        return hash;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj == null) {
+            return false;
+        }
+        if (!(obj instanceof EmailAddress)) {
+            return false;
+        }
+        final EmailAddress other = (EmailAddress) obj;
+        if (this.email == null || other.email == null) {
+            return this == obj;
+        }
+        if(!this.email.equals(other.email)) {
+            return this == obj;
+        }
+        return true;
+    }
+
+    @Override
+    public String toString() {
+        return "com.clevercure.web.hibernateissuecache.EmailAddress[ email=" + email + " ]";
+    }
+}

hibernate-core/src/test/java/org/hibernate/test/collection/set/hhh8206/JoinFetchElementCollectionTest.java

@@ -0,0 +1,61 @@
+package org.hibernate.test.collection.set.hhh8206;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Set;
+
+import org.hibernate.Session;
+import org.hibernate.testing.junit4.BaseCoreFunctionalTestCase;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class JoinFetchElementCollectionTest extends BaseCoreFunctionalTestCase {
+	@Override
+	protected Class<?>[] getAnnotatedClasses() {
+		return new Class[] {Contact.class, EmailAddress.class, User.class};
+	}
+	
+	@Test
+	public void test(){
+        Set<EmailAddress> emailAddresses = new HashSet<EmailAddress>();
+        emailAddresses.add(new EmailAddress("test1@test.com"));
+        emailAddresses.add(new EmailAddress("test2@test.com"));
+        emailAddresses.add(new EmailAddress("test3@test.com"));
+        
+		{
+			// Session 1: Insert a user with email addresses but no emailAddresses2
+			Session session = openSession();
+			session.beginTransaction();
+			
+			User user = new User();
+	        user.setName("john");
+	        Contact contact = new Contact();
+	        contact.setName("John Doe");
+	        contact.setEmailAddresses(emailAddresses);
+	        contact = (Contact) session.merge(contact);
+	        user.setContact(contact);
+	        user = (User) session.merge(user);
+
+			session.getTransaction().commit();
+			session.close();
+		}
+		{
+			// Session 2: Retrieve the user object and check if the sets have the expected values
+			Session session = openSession();
+			session.beginTransaction();
+			User user = (User) session.createQuery("SELECT user "
+					+ "FROM User user "
+					+ "LEFT OUTER JOIN FETCH user.contact "
+					+ "LEFT OUTER JOIN FETCH user.contact.emailAddresses2 "
+					+ "LEFT OUTER JOIN FETCH user.contact.emailAddresses")
+					.uniqueResult();
+			session.getTransaction().commit();
+			session.close();
+
+			Assert.assertEquals(emailAddresses, user.getContact().getEmailAddresses());
+			Assert.assertTrue(user.getContact().getEmailAddresses2().isEmpty());
+		}
+		
+	}
+
+}

hibernate-core/src/test/java/org/hibernate/test/collection/set/hhh8206/User.java

@@ -0,0 +1,87 @@
+package org.hibernate.test.collection.set.hhh8206;
+
+import java.io.Serializable;
+import java.util.HashSet;
+import java.util.Set;
+import javax.persistence.Basic;
+import javax.persistence.CollectionTable;
+import javax.persistence.ElementCollection;
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.ManyToMany;
+import javax.persistence.ManyToOne;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
+
+@Entity
+@Table(name="users")
+public class User implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+    private Long id;
+    private String name;
+    private Contact contact;
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    @Basic
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    @ManyToOne(optional = true)
+    @JoinColumn(name = "contact_id", nullable = true, unique = true)
+    public Contact getContact() {
+            return contact;
+    }
+
+    public void setContact(Contact contact) {
+            this.contact = contact;
+    }
+
+    @Override
+    public int hashCode() {
+        int hash = 0;
+        hash += (id != null ? id.hashCode() : 0);
+        return hash;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj == null) {
+            return false;
+        }
+        if (!(obj instanceof User)) {
+            return false;
+        }
+        final User other = (User) obj;
+        if (this.id == null || other.id == null) {
+            return this == obj;
+        }
+        if(!this.id.equals(other.id)) {
+            return this == obj;
+        }
+        return true;
+    }
+
+    @Override
+    public String toString() {
+        return "com.clevercure.web.hibernateissuecache.User[ id=" + id + " ]";
+    }
+}