bidrectional foregin key one to one

spring-hibernate4/src/main/java/org/baeldung/spring/persistence/model/Child.java

@@ -3,11 +3,9 @@ package org.baeldung.spring.persistence.model;
 import java.io.Serializable;
 
 import javax.persistence.Entity;
-import javax.persistence.FetchType;
 import javax.persistence.GeneratedValue;
 import javax.persistence.Id;
 import javax.persistence.OneToOne;
-import javax.persistence.PrimaryKeyJoinColumn;
 
 @Entity
 public class Child implements Serializable {
@@ -16,8 +14,7 @@ public class Child implements Serializable {
     @GeneratedValue
     private long id;
 
-    @OneToOne(fetch = FetchType.LAZY)
-    @PrimaryKeyJoinColumn
+    @OneToOne(mappedBy = "child")
     private Parent parent;
 
     public Child() {
@@ -34,7 +31,6 @@ public class Child implements Serializable {
         this.id = id;
     }
 
-    @OneToOne(mappedBy = "child")
     public Parent getParent() {
         return parent;
     }

spring-hibernate4/src/main/java/org/baeldung/spring/persistence/model/Parent.java

@@ -16,6 +16,8 @@ public class Parent implements Serializable {
     @GeneratedValue
     private long id;
 
+    @OneToOne(cascade = CascadeType.ALL)
+    @JoinColumn(name = "child_fk")
     private Child child;
 
     public Parent() {
@@ -38,8 +40,6 @@ public class Parent implements Serializable {
         this.id = id;
     }
 
-    @OneToOne(cascade = CascadeType.ALL)
-    @JoinColumn(name = "child_fk")
     public Child getChild() {
         return child;
     }

spring-hibernate4/src/test/java/org/baeldung/spring/persistence/service/ParentServicePersistenceIntegrationTest.java

@@ -28,7 +28,7 @@ public class ParentServicePersistenceIntegrationTest {
     }
 
     @Test
-    public final void whenEntityIsCreated_thenNoExceptions() {
+    public final void whenOneToOneEntitiesAreCreated_thenNoExceptions() {
         final Child childEntity = new Child();
         childService.create(childEntity);
 
@@ -42,4 +42,15 @@ public class ParentServicePersistenceIntegrationTest {
         System.out.println("Parent - child = " + service.findOne(parentEntity.getId()).getChild());
     }
 
+    @Test
+    public final void whenChildIsDeleted_thenDataException() {
+        final Child childEntity = new Child();
+        childService.create(childEntity);
+
+        final Parent parentEntity = new Parent(childEntity);
+        service.create(parentEntity);
+
+        childService.delete(childEntity);
+    }
+
 }