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Why a Non-Null Kotlin Property Is Null When the Base Class Init Calls an Open Function

October 5, 2026 by Arsam

Syntax-highlighted code on a dark screen, illustrating why a non-null Kotlin property is null during base class init

A non-null Kotlin property is null when a base class init calls an open function. Why the subclass fields are unset, why it compiles, and the fix.

Categories Bug-Squash Interview, OOP/SOLID Interview Tags android, interview-prep, kotlin, null-safety, oop-solid, technical-interview Leave a comment

Why Your Kotlin Data Class’s equals() Ignores the Parent Class

September 27, 2026September 24, 2026 by Arsam

Close-up of colorful source code on a computer monitor

The Kotlin data class equals check ignores a parent class’s properties, by design. Why, the hashCode trap in the obvious fix, a correct override and the interview answer.

Categories Bug-Squash Interview, OOP/SOLID Interview Tags android, data-class, equals-hashcode, interview-prep, kotlin, oop-solid, technical-interview 1 Comment

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