```try myObject theField catch t Throwable log error theFiel

Question

```try myObject theField catch t Throwable log error theField is null ```

horse_badorties · Answer

can you provide the declaration of your data class please

horse_badorties · Answer

```data class Foo val name String val myFoo = Foo null ``` does not compile there is no way of getting a Foo with a null name the compiler prevents that

ribesg · Answer

There are multiple obvious ways to have null values in non null fields

horse_badorties · Answer

show me one slightly smiling face

ribesg · Answer

I guess the most obvious one is reflection

ribesg · Answer

In my specific case it s Moshi

ribesg · Answer

Retrofit with a MoshiConverter

horse_badorties · Answer

ok so we are talking about Interop issues

ribesg · Answer

Most things running on the JVM do not care about nullability

horse_badorties · Answer

I wasn t aware you were talking about kotlin only

ribesg · Answer

You can t do much with Kotlin only stuck out tongue

horse_badorties · Answer

ok I just did a quick test with a simple static Java method that returns a null String reference `myObject theField = JavaTester returnNull ` throws an `IllegalStateException`

horse_badorties · Answer

oops one moment slightly smiling face

horse_badorties · Answer

reflection might work though

ribesg · Answer

You need either reflection or the Java part stating it doesn t return null using annotations while still returning null

ribesg · Answer

A simple Java method returning a `String` is considered to return a `String ` to a Kotlin caller

horse_badorties · Answer

exactly

ribesg · Answer

Now if you put ` NotNull` on your Java method and still return null Kotlin is lost

horse_badorties · Answer

which NotNull exactly There are many

ribesg · Answer

Any of those understood by the Kotlin compiler I guess

horse_badorties · Answer

I tried org jetbrains annotations NotNull

ribesg · Answer

Which should be the same as the ones understood by IDEA by default

horse_badorties · Answer

still IllegalStateException

ribesg · Answer

The Java part needs to be compiled separately

horse_badorties · Answer

org jetbrains annotations NotNull is the IDEA default yeah

ribesg · Answer

It needs to be a compiled library

horse_badorties · Answer

ok I see

ribesg · Answer

If it s your own file that you compile at the same time then it knows

ribesg · Answer

Another problem is that you really never know how all the alibraries you use work they may use reflection and you don t know it

ribesg · Answer

My problem on the Kotlin side is that Kotlin never checks for that null This object held a null value for days in the RAM then at some point somebody did an action which passed this value to a method which doesn t take nulls and boom It should have failed earlier It was very hard to trace

horse_badorties · Answer

I see You might want to ask again in the channel and provide a little more background