Is it possible to get a NullPointerException in Kotlin?

Yes, it is possible. Despite the strict type system and nullable types (?), a NullPointerException can occur in the following cases:

• Calling Java code without null-safety annotations: If a Java method returns null, and this method is called in Kotlin without an explicit null check, Kotlin may throw a NullPointerException when trying to access members of this object.

• Using the !! operator (non-null asserted call): This operator explicitly indicates that the value cannot be null. If it is null, a NullPointerException will be thrown.

  // Example of using the "!!" operator
  var nullableString: String? = null
  val nonNullString: String = nullableString!! // Will throw NullPointerException
  

• Uninitialized lateinit var: If a variable declared with the lateinit keyword is used before initialization, an UninitializedPropertyAccessException will be thrown, which is a subclass of RuntimeException and is similar in nature to NullPointerException.

• Violation of the @NonNull contract in Java code: If a Java method annotated with @NonNull actually returns null, calling it from Kotlin may result in a NullPointerException.

• Interoperability issues with C/C++: Kotlin code interacting with native code via JNI. Errors in native code or incorrect pointer handling can lead to crashes or NullPointerException in the JVM.