Android Sqlite Multi Threading Save Data With Dbflow + Retrofit

I'm using DBFlow to save into the database and Retrofit to call my web service. My retrofit class is the same class as my Database table. But I have a problem when 2 threads or mor

Solution 1:

What you are doing here is the first "dont' do" in the docs of DBFlow. What you should use here is a transaction to store the data. This locks the database for an exclusive batch operation and should be a lot faster than iterating over all you models and save them one by one.

Basically, you want to use FastStoreModelTransaction.saveBuilder() here which basically does a INSERT OR UPDATE.

Usage would be like that:

publicvoidonResponse(Call<AdminPictures> call, Response<AdminPictures> response) {
    AdminPicturesapResponse= response.body();
    final List<PictureInfos> pictureInfos = apResponse.getPicturesList();

    FastStoreModelTransactiontransaction= FastStoreModelTransaction.saveBuilder(FlowManager.getModelAdapter(PictureInfos.class))
        .addAll(pictureInfos)
        .build();

    database.executeTransaction(transaction);
}

Please note that this would automatically runs in the background, so no need to wrap it in an extra thread. If you need a listener on the storing process, use the ProcessModelTransaction instead.

Solution 2:

Reading database can be done in parallel without interrupting each other, but writing in to database should be done in a synchronized way if you have keys.

You should write the save within a synchronized method. Synchronize will allow only one thread to do changes at a time.

Note: By default android SQLiteDatabase Object is safe for multithreading. DBFlow is also. Make sure you are using the same instances of helpers in multiple threads.

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