Forgot to add files

src/app/core/cache/models/normalized-dspace-object-factory.ts

+import { NormalizedDSpaceObject } from "./normalized-dspace-object.model";
+import { NormalizedBitstream } from "./normalized-bitstream.model";
+import { NormalizedBundle } from "./normalized-bundle.model";
+import { NormalizedItem } from "./normalized-item.model";
+import { NormalizedCollection } from "./normalized-collection.model";
+import { GenericConstructor } from "../../shared/generic-constructor";
+import { NormalizedDSOType } from "./normalized-dspace-object-type";
+
+export class NormalizedDSOFactory {
+  public static getConstructor(type: NormalizedDSOType): GenericConstructor<NormalizedDSpaceObject> {
+      switch (type) {
+      case NormalizedDSOType.NormalizedBitstream: {
+        return NormalizedBitstream
+        }
+      case NormalizedDSOType.NormalizedBundle: {
+        return NormalizedBundle
+        }
+      case NormalizedDSOType.NormalizedItem: {
+        return NormalizedItem
+        }
+      case NormalizedDSOType.NormalizedCollection: {
+        return NormalizedCollection
+        }
+        default: {
+          return undefined;
+        }
+      }
+  }
+}

src/app/core/cache/models/normalized-dspace-object-type.ts

+export enum NormalizedDSOType {
+  NormalizedBitstream,
+  NormalizedBundle,
+  NormalizedItem,
+  NormalizedCollection
+}