Replace exist field from json that not content this field?

POJO:

public class Offer extends RealmObject {
    @PrimaryKey
    private int id;
    private String name;
    private boolean downloaded;
}

I update field “download” by true like this (click special button in my app):

public static void update(final int offerId, final boolean downloaded) {
        Realm realm = Realm.getDefaultInstance();
        try {
            realm.executeTransaction(new Realm.Transaction() {
                @Override
                public void execute(Realm realm) {
                    Offer offer = realm.where(Offer.class).equalTo(Offer.ID, offerId).findFirst();
                    offer.setDownloaded(downloaded);
                }
            });
        } finally {
            realm.close();
        }
    }

OK. It’s work. Now field download = true. And I need this field not change any more!

But then incoming json like this (in this json no field “download”)

[
  {
    "id": 1,
    "name": "my name"
  },
  {
    "id": 2,
    "name": "my name2"
  }
  ]

I update Offer like this :

public static void updateOffers(final List<Offer> offersList) {
    Realm realm = Realm.getDefaultInstance();
    try {
        realm.executeTransaction(new Realm.Transaction() {
            @Override
            public void execute(Realm realm) {
                RealmList<Offer> offersRealmList = new RealmList<>();
                offersRealmList.addAll(offersList);
                realm.copyToRealmOrUpdate(offersRealmList);
            }
        });
    } finally {
        realm.close();
    }
}

And after this update all fields “download” again = FALSE!!!

Questions: 1.This is a normal of Realm to replace exist field? (In json no this field) 2.How avoid to replace filed “download”?

[beeender]

yes, that would be a fine solution for now.

We have an issue to track this #2288

[alexei-28]

Note: When client click button(download) field Offer.download = true and MUST never change!

So as result here my solution:

public class Store extends RealmObject {
    @PrimaryKey
    private int id;
    private String name;
    private RealmList<Offer> offers = new RealmList<>();
}


public class Offer extends RealmObject {
    @PrimaryKey
    private int id;
    private String name;
    private boolean downloaded;
}

Get all offers with download = true;

public static List<Offer> getoffersList(boolean downloaded) {
        Realm realm = Realm.getDefaultInstance();
        try {
            List<Offer> offersList = new ArrayList<>();
            RealmResults<Offer> realmResults = realm.where(Offer.class).equalTo(Offer.DOWNLOADED ,true).findAll();
            offersList.addAll(realm.copyFromRealm(realmResults));
            return offersList;
        } finally {
            realm.close();
        }
    }

Algorithm:

1. offersDownloadTrueList - Get all offers with download = true
2. Iterate list of stores and find offers that exist in list offersDownloadTrueList
3. Replace field download by value true (by default it’s value is false)
4. update Realm with cnanged newStoresList

newStoresList - create from incoming Json (without field “download”)

Here implementation:

 public static void updateStores(final List<Store> newStoresList) {
             Realm realm = Realm.getDefaultInstance();
        try {
            realm.executeTransaction(new Realm.Transaction() {
                @Override
                public void execute(Realm realm) {
                    List<Offer> offersDownloadTrueList = OfferService.getoffersList(true);
                    for (Store store : newStoresList) {
                        List<Offer> newOffersList = store.getOffers();
                        for (Offer newOffer : newOffersList) {
                            if (offersDownloadTrueList.contains(newOffer)) {
                                Debug.d(TAG, "execute: Found_offer_with field 'download' =  true,  offerId = " + newOffer.getId());
                                newOffer.setDownloaded(true);
                            }
                        }
                    }

                    RealmList<Store> storesRealmList = new RealmList<>();
                    storesRealmList.addAll(newStoresList);
                    realm.copyToRealmOrUpdate(storesRealmList);
                }
            });
        } finally {
            realm.close();
        }
}

And now in Realm offers that has field download = true not change. OK. It’s work. Fine.

The question is: Is this a best solution?