Add example for inMemory room database

Author: anandgaurav10

app/src/main/java/com/sample/MainActivity.java

@@ -125,6 +125,18 @@ protected void onCreate(Bundle savedInstanceState) {
             userDBHelper.insertUser(userList);
         }
 
+        // Room inMemory database
+        if (userDBHelper.countInMemory() == 0) {
+            List<User> userList = new ArrayList<>();
+            for (int i = 0; i < 20; i++) {
+                User user = new User();
+                user.id = (long) (i + 1);
+                user.name = "in_memory_user_" + i;
+                userList.add(user);
+            }
+            userDBHelper.insertUserInMemory(userList);
+        }
+
         Utils.setCustomDatabaseFiles(getApplicationContext());
     }
 

app/src/main/java/com/sample/database/room/UserDBHelper.java

@@ -12,19 +12,29 @@
 public class UserDBHelper {
 
     private final AppDatabase appDatabase;
+    private final AppDatabase inMemoryAppDatabase;
 
     public UserDBHelper(Context context) {
         appDatabase = Room.databaseBuilder(context, AppDatabase.class, "User-Database")
                 .allowMainThreadQueries()
                 .build();
+        inMemoryAppDatabase = Room.inMemoryDatabaseBuilder(context, AppDatabase.class).build();
     }
 
     public void insertUser(List<User> userList) {
         appDatabase.userDao().insertAll(userList);
     }
 
+    public void insertUserInMemory(List<User> userList) {
+        inMemoryAppDatabase.userDao().insertAll(userList);
+    }
+
     public int count() {
         return appDatabase.userDao().loadAll().size();
     }
 
+    public int countInMemory() {
+        return inMemoryAppDatabase.userDao().loadAll().size();
+    }
+
 }