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diff --git a/src/com/android/car/messenger/core/interfaces/AppFactory.java b/src/com/android/car/messenger/core/interfaces/AppFactory.java
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+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.car.messenger.core.interfaces;
+
+import android.content.Context;
+import android.content.SharedPreferences;
+
+import androidx.annotation.NonNull;
+
+/**
+ * The AppFactory provides singleton instances to be used throughout the app.
+ *
+ * <p>The Factory implementation points to the UI core library interfaces.
+ *
+ * <p>Once the Factory implementation is initialized with {@link #setInstance(AppFactory)}, the
+ * library interface implementations can be accessed anywhere throughout the application.
+ */
+public abstract class AppFactory {
+    @NonNull private static AppFactory sInstance;
+    protected static boolean sRegistered;
+    protected static boolean sInitialized;
+
+    /** Returns the Factory instance for the Application. */
+    @NonNull
+    public static AppFactory get() {
+        return sInstance;
+    }
+
+    /**
+     * Sets the Factory instance.
+     *
+     * <p>This is called when the application starts, in onCreate of the custom Application class
+     */
+    protected static void setInstance(@NonNull final AppFactory factory) {
+        // Not allowed to call this after real application initialization is complete
+        if (sRegistered && sInitialized) {
+            return;
+        }
+        sInstance = factory;
+    }
+
+    /** Returns context most appropriate for UI context-requiring tasks. */
+    @NonNull
+    public abstract Context getContext();
+
+    /**
+     * Perhaps the single most important methods to implement, this provides the data source for the
+     * app.
+     */
+    @NonNull
+    public abstract DataModel getDataModel();
+
+    /** Returns the shared preference instance for the app */
+    @NonNull
+    public abstract SharedPreferences getSharedPreferences();
+}