fixes NullPointerException with entities using transient fields in detached mode

spring-data-neo4j/src/main/java/org/springframework/data/neo4j/fieldaccess/DetachedEntityState.java

@@ -43,8 +43,8 @@ public class DetachedEntityState<ENTITY extends GraphBacked<STATE>, STATE> imple
     private final Map<Field, ExistingValue> dirty = new HashMap<Field, ExistingValue>();
     protected final EntityState<ENTITY,STATE> delegate;
     private final static Log log = LogFactory.getLog(DetachedEntityState.class);
-    private GraphDatabaseContext graphDatabaseContext;
-    private Neo4JPersistentEntity<ENTITY> persistentEntity;
+    private final GraphDatabaseContext graphDatabaseContext;
+    private final Neo4JPersistentEntity<ENTITY> persistentEntity;
 
     public DetachedEntityState(final EntityState<ENTITY, STATE> delegate, GraphDatabaseContext graphDatabaseContext) {
         this.delegate = delegate;
@@ -134,7 +134,13 @@ private boolean mustCheckConcurrentModification() {
     }
     @Override
     public Object setValue(final Field field, final Object newVal) {
-        return setValue(property(field),newVal);
+    	Neo4JPersistentProperty property = property(field);
+    	if (property == null) {
+    		// The property maybe null if it is a transient field
+    		return newVal;
+    	}
+
+        return setValue(property, newVal);
     }
 
     private Neo4JPersistentProperty property(Field field) {
@@ -146,7 +152,6 @@ public Object setValue(final Neo4JPersistentProperty property, final Object newV
         if (isDetached()) {
             final Field field = property.getField();
             if (!isDirty(field) && isWritable(field)) {
-                Object existingValue;
                 if (hasPersistentState()) {
                     addDirty(field, unwrap(delegate.getValue(field)), true);
                 }

spring-data-neo4j/src/main/java/org/springframework/data/neo4j/fieldaccess/OneToNRelationshipEntityFieldAccessorFactory.java

@@ -30,6 +30,11 @@
 import org.springframework.data.neo4j.support.GraphBackedEntityIterableWrapper;
 import org.springframework.data.neo4j.support.GraphDatabaseContext;
 
+import java.util.HashSet;
+import java.util.Set;
+
+import static org.springframework.data.neo4j.support.DoReturn.doReturn;
+
 public class OneToNRelationshipEntityFieldAccessorFactory implements FieldAccessorFactory<NodeBacked> {
 
 	private GraphDatabaseContext graphDatabaseContext;

spring-data-neo4j/src/test/java/org/springframework/data/neo4j/support/PropertyTest.java

@@ -70,7 +70,13 @@ public void testGetPropertyEnum() {
         p.getPersistentState().setProperty("personality", "EXTROVERT");
         assertEquals("Did not deserialize property value properly.", Personality.EXTROVERT, p.getPersonality());
     }
-
+    @Test
+    @Transactional
+    public void testSetTransientPropertyFieldInDetachedMode() {
+        Person p = new Person("Michael", 35);
+        p.setThought("food"); // caused a NullPointerException
+    }
+
     @Test(expected = NotFoundException.class)
     @Transactional
     public void testSetTransientPropertyFieldNotManaged() {