Deep copy of list with objects in Kotlin

Question

I am new to kotlin and I am trying to make a copy of a list of objects.The problem I am having is that when I change items in the new copy, the old list gets changed as well

Answer 1

This is not related to kotlin, when you are adding the objects from the old list to the new one, it add the reference to them (no createing a new object ), whats mean it just copying the address in the memory to the new list.

To fix this problem you should create a new instance for each object. you can create a copy constructor, for example:

constructor(otherA: ClassA) {
    this.prop1 = otherA.prop1
    this.prop2 = otherA.prop2
    ...
} 

and then add them one by one to the new list:

list1.forEach { list2.add(Class(it)) }