Kotlin compare two lists - if ids match overwrite it [closed] - kotlin

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I have two lists of Object. Both objects have an id val. I need to check both lists by the id val, if the id is the same take the object from list B and overwrite it in list A. Is there a simple up to date way to achieve this outcome in kotlin?
Ive been searching through the kotlin docs and other comparing list questions on here but I havent found anything in the docs or on here that matches my usecase

Answer 1

Not sure about how efficient this is but it works...
Sample Class
data class SomeClass(val id: Int, val someString: String) {
}
fun transformList(firstList: List<SomeClass>, secondList: List<SomeClass>): List<SomeClass> {
return firstList.map { firstClass ->
val tempItem = secondList.firstOrNull { it.id == firstClass.id }
tempItem ?: firstClass
}
}
basically, the function takes both the lists and compares each item with each other, and returns items from list 2 if the id is the same.
fun main() {
val listOne = listOf<SomeClass>(
SomeClass(0, "I am 0, from list 1"),
SomeClass(1, "I am 1, from list 1"),
)
val listTwo = listOf<SomeClass>(
SomeClass(0, "I am 0, from list 2"),
SomeClass(1, "I am 1, from list 2"),
)
println(transformList(listOne, listTwo))
}
Output
[SomeClass(id=0, someString=I am 0, from list 2), SomeClass(id=1, someString=I am 1, from list 2)]