HHH-9897 - @onetomany association with @JoinFormula throws NPE

(cherry picked from commit 53dfed4)

Author: sebersole

hibernate-core/src/main/java/org/hibernate/cfg/Ejb3Column.java

@@ -182,7 +182,7 @@ public void setUnique(boolean unique) {
 	}
 
 	public boolean isNullable() {
-		return mappingColumn.isNullable();
+		return isFormula() ? true : mappingColumn.isNullable();
 	}
 
 	public String getDefaultValue() {

hibernate-core/src/test/java/org/hibernate/test/annotations/formula/JoinColumnOrFormulaTest.java

@@ -0,0 +1,87 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.test.annotations.formula;
+
+import java.util.HashSet;
+import java.util.Set;
+import javax.persistence.Column;
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
+
+import org.hibernate.SessionFactory;
+import org.hibernate.annotations.JoinColumnOrFormula;
+import org.hibernate.annotations.JoinColumnsOrFormulas;
+import org.hibernate.annotations.JoinFormula;
+import org.hibernate.boot.Metadata;
+import org.hibernate.boot.MetadataSources;
+import org.hibernate.boot.registry.StandardServiceRegistry;
+import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
+
+import org.hibernate.testing.FailureExpected;
+import org.hibernate.testing.TestForIssue;
+import org.hibernate.testing.junit4.BaseUnitTestCase;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+/**
+ * @author Steve Ebersole
+ */
+public class JoinColumnOrFormulaTest extends BaseUnitTestCase {
+	private StandardServiceRegistry ssr;
+
+	@Before
+	public void before() {
+		ssr = new StandardServiceRegistryBuilder().build();
+	}
+
+	@After
+	public void after() {
+		if ( ssr != null ) {
+			StandardServiceRegistryBuilder.destroy( ssr );
+		}
+	}
+
+	@Test
+	@TestForIssue( jiraKey = "HHH-9897" )
+	@FailureExpected( jiraKey = "HHH-9897" )
+	public void testUseOfJoinColumnOrFormula() {
+		Metadata metadata = new MetadataSources()
+				.addAnnotatedClass( A.class )
+				.addAnnotatedClass( D.class )
+				.buildMetadata();
+
+		// Binding to the mapping model works after the simple change for HHH-9897
+		// But building the SessionFactory fails in the collection persister trying to
+		// use the formula (it expects Columns too)
+		metadata.buildSessionFactory().close();
+	}
+
+	@Entity( name = "A" )
+	@Table( name = "A" )
+	public static class A {
+		@Id
+		@Column( name = "idA")
+		public Integer id;
+
+		@OneToMany
+		@JoinColumnsOrFormulas({
+				@JoinColumnOrFormula(formula = @JoinFormula(value = "idA", referencedColumnName = "idA"))
+		})
+		Set<D> ds = new HashSet<D>();
+	}
+
+	@Entity( name = "D" )
+	@Table( name = "D" )
+	public static class D {
+		@Id
+		@Column( name = "idA")
+		public Integer idA;
+	}
+}