Realm-java: RealmList<Date> has invalid size value

[kumien]

I have used RealmList for Date object and I have faced a problem with size value. In my case in debbuger I can see only 4 items but size() method shows 5. Because of that loop isn't working correctly.

Please look on attached screenshot.

Version of Realm and tooling

Realm version(s): 4.0.0-RC1

Realm sync feature enabled: no

Android Studio version: 2.3.3

Which Android version and device: 6.0

[Zhuinden]

Any chance that the date at index 4 is null?

Or does it throw IndexOutOfBoundsException?

Can you please verify getStartDates().get(4) in debugger?

[kumien]

It is null.

[cmelchior]

But if there is a null item at index[4], size() == 5 is correct? We have unit tests showing this behaviour: https://github.com/realm/realm-java/blob/master/realm/realm-library/src/androidTest/java/io/realm/ManagedRealmListForValueTests.java#L474

[Zhuinden]

@kumien are you sure you never manually inserted null as a parameter in that list?

@cmelchior I didn't realize you can store nulls in primitive lists, is it possible to make a primitive list store only non-null values with @Required?

[beeender]

@Zhuinden Yes, by using @Required, the primitive list will only store non-null values.

[kumien]

Whole object was parsed from json and there wasn't null value. Even if I will add null value to list then it should be visible in the list. Otherwise size() method has to inform how much items we have in the list.

[cmelchior]

Not sure what you mean by it being "visible in the list"? The Android debugger apparently doesn't show null values in lists (I don't know if that is a setting somewhere), but that isn't Java's problem. If you call list.get(4) you correctly get null back, making the size 5.

But if there is a bug in how we import list data we want to get that fixed as soon as possible. Do you have the data and import code that shows this happening?

[Zhuinden]

Android debugger doesn't show null as last element of list automatically, I ran into this before while debugging FragmentManager-related things where instead of just removing the fragment, they set its index to null.

[cmelchior]

null values are hidden by default. Really strange default setting if you ask me 😞

[cmelchior]

@kumien I assume the above answered your question, if not feel free to reopen.