Kotlin List iterator()
Syntax & Examples

Syntax of List.iterator()

The syntax of List.iterator() function is:

abstract fun iterator(): Iterator<E>

This iterator() function of List returns an iterator over the elements of this object.

✐ Examples

1 Example

In this example,

We create a list named list1 containing the elements 'a', 'b', 'c'.
We obtain an iterator over list1 using the List iterator() function.
We iterate over the elements using a while loop, checking if the iterator has more elements with hasNext() and retrieving each element with next().
Each element is printed to standard output using the println function.

Kotlin Program

fun main(args: Array<String>) {
    val list1 = listOf("a", "b", "c")
    val iterator = list1.iterator()
    while (iterator.hasNext()) {
        val element = iterator.next()
        println(element)
    }
}

Output

a
b
c

2 Example

In this example,

We create a list named list2 containing the integers 10, 20, 30.
We obtain an iterator over list2 using the List iterator() function.
We iterate over the elements using a for loop, which internally uses the iterator to access each element.
Each element is printed to standard output using the println function.

Kotlin Program

fun main(args: Array<String>) {
    val list2 = listOf(10, 20, 30)
    val iterator = list2.iterator()
    for (item in iterator) {
        println(item)
    }
}

Output

10
20
30

Summary

In this Kotlin tutorial, we learned about iterator() function of List: the syntax and few working examples with output and detailed explanation for each example.