package SubscribedUserDatabase; import android.arch.persistence.room.Database; import android.arch.persistence.room.Room; import android.arch.persistence.room.RoomDatabase; import android.content.Context; @Database(entities = {SubscribedUserData.class}, version = 1) public abstract class SubscribedUserRoomDatabase extends RoomDatabase { private static SubscribedUserRoomDatabase INSTANCE; public abstract SubscribedUserDao subscribedUserDao(); public static SubscribedUserRoomDatabase getDatabase(final Context context) { if(INSTANCE == null) { synchronized (SubscribedUserRoomDatabase.class) { if(INSTANCE == null) { INSTANCE = Room.databaseBuilder(context.getApplicationContext(), SubscribedUserRoomDatabase.class, "subscribed_users") .build(); } } } return INSTANCE; } }