Remove getEnum-API.

This removes the new API on the AnnotationInfo. This API was very well done and tested, but it increases our surface again and we don’t want that. It’s needed in two places and it’s ok to duplicate it the instantiation there.

There’s one signifacant change we’re we check whether the attribute is an enum or not.  For comparision: #644

core/src/main/java/org/neo4j/ogm/metadata/AnnotationInfo.java

@@ -26,6 +26,7 @@
 
 import org.apache.commons.lang3.StringUtils;
 import org.neo4j.ogm.annotation.ValueFor;
+import org.neo4j.ogm.support.ClassUtils;
 
 /**
  * @author Vince Bickers
@@ -41,7 +42,7 @@ private static String convert(Method element, Object value) {
             return String.valueOf(value);
         } else if (returnType.equals(Class.class)) {
             return ((Class) value).getName();
-        } else if (Enum.class.isAssignableFrom(returnType)) {
+        } else if (ClassUtils.isEnum(returnType)) {
             return ((Enum<?>) value).name();
         } else {
             final String result = value.toString();
@@ -105,27 +106,10 @@ public Annotation getAnnotation() {
     }
 
     public String get(String key, String defaultValue) {
-        elements.putIfAbsent(key, defaultValue);
-        return get(key);
+        return elements.computeIfAbsent(key, k -> defaultValue);
     }
 
     public String get(String key) {
         return elements.get(key);
     }
-
-    @SuppressWarnings("unchecked")
-    public <T extends Enum<T>> T getEnum(String key, T defaultValue) {
-        elements.putIfAbsent(key, defaultValue.name());
-        return (T) getEnum(defaultValue.getClass(), key);
-    }
-
-    public <T extends Enum<T>> T getEnum(Class<T> enumType, String key) {
-        String currentValue = elements.get(key);
-        if (currentValue == null) {
-            return null;
-        }
-
-        return T.valueOf(enumType, currentValue);
-    }
-
 }

core/src/main/java/org/neo4j/ogm/metadata/FieldInfo.java

@@ -227,7 +227,7 @@ public Direction relationshipDirectionOrDefault(Direction defaultDirection) {
             if (annotationInfo == null) {
                 return defaultDirection;
             }
-            return annotationInfo.getEnum(Relationship.DIRECTION, defaultDirection);
+            return Direction.valueOf(annotationInfo.get(Relationship.DIRECTION, defaultDirection.name()));
         }
         throw new RuntimeException("relationship direction call invalid");
     }

core/src/main/java/org/neo4j/ogm/metadata/schema/Relationship.java

@@ -18,6 +18,8 @@
  */
 package org.neo4j.ogm.metadata.schema;
 
+import org.neo4j.ogm.annotation.Relationship.Direction;
+
 /**
  * Relationship in a {@link Schema}
  *
@@ -35,7 +37,7 @@ public interface Relationship {
      *
      * @return direction
      */
-    org.neo4j.ogm.annotation.Relationship.Direction direction(Node node);
+    Direction direction(Node node);
 
     /**
      * Return start node of this relationship

core/src/main/java/org/neo4j/ogm/session/delegates/SessionDelegate.java

@@ -24,7 +24,7 @@
 import org.neo4j.ogm.annotation.EndNode;
 import org.neo4j.ogm.annotation.Property;
 import org.neo4j.ogm.annotation.Relationship;
-import org.neo4j.ogm.annotation.Relationship.*;
+import org.neo4j.ogm.annotation.Relationship.Direction;
 import org.neo4j.ogm.annotation.StartNode;
 import org.neo4j.ogm.cypher.Filter;
 import org.neo4j.ogm.cypher.FilterWithRelationship;
@@ -112,7 +112,9 @@ private void updateRelationship(FilterWithRelationship filter, FieldInfo fieldIn
             AnnotationInfo annotation = fieldInfo.getAnnotations().get(Relationship.class);
             if (annotation != null) {
                 filter.setRelationshipType(annotation.get(Relationship.TYPE, relationshipType));
-                filter.setRelationshipDirection(annotation.getEnum(Relationship.DIRECTION, Direction.UNDIRECTED));
+                Direction direction = Direction
+                    .valueOf(annotation.get(Relationship.DIRECTION, Direction.UNDIRECTED.name()));
+                filter.setRelationshipDirection(direction);
             }
             if (fieldInfo.getAnnotations().get(StartNode.class) != null) {
                 filter.setRelationshipDirection(Direction.OUTGOING);