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Android

Tim Kuzmin
Tim Kuzmin
7,812 Points
Posted by Tim Kuzmin
Tim Kuzmin
7,812 Points

Immutable vs Final. Kotlin vs Java.

Hello! Thanks for this course - it's cool c: Are we using mutable and immutable terms correctly here? In Java, this means means something like this: "Mutable objects have fields that can be changed, immutable objects have no fields that can be changed after the object is created.". Does "immutable" means Javas "final" or not? Why do we call some properties "immutable" (if they just "read-only")? Can we change inside properties in val properties?

1 Answer

Tawanda Mukungureyi
Tawanda Mukungureyi
7,361 Points
Tawanda Mukungureyi
Tawanda Mukungureyi
7,361 Points

Hie, note that 'immutable' is applicable to objects only whilst 'final' keyword is applied to variables

Tim Kuzmin
Tim Kuzmin
7,812 Points
Tim Kuzmin
Tim Kuzmin
7,812 Points

to variables of this object, right?

Actually I think I got it, but in video we'd say that val means immutable(if I correctly understood). I think that it's not right. Val is read-only - val property can contain mutable object too. May be author meant something like: "this property now immutable", but that also wrong - we use term "immutable" when we speak about objects.

Are you agree with this?