Array
<![CDATA[
fun main(args: Array<String>) {
// Elements : 32 0 0 54 0
// Index : 0 1 2 3 4
var myArray = Array<Int>(5) { 0 } // Mutable. Fixed Size.
myArray[0] = 32
myArray[3] = 54
myArray[1] = 11
for (element in myArray) { // Using individual elements (Objects)
println(element)
}
println()
for (Index in 0..myArray.size - 1) {
println(myArray[index])
}
}
]]>
Collection
List
<![CDATA[
fun main(args: Array<String>) {
// Elements :
// Index : 0 1 2 3 4
// var list = mutableListOf<String>() // Mutable, No Fixed Size, Can Add or Remove Elements
// var list = arrayListOf<String>() // Mutable, No Fixed Size, Can Add or Remove Elements
var list = ArrayList<String>() // Mutable, No Fixed Size, Can Add or Remove Elements
list.add("Yogi") // 0
list.add("Manmohan") // 1
list.add("Vajpayee") // 2
// list.remove("Manmohan")
// list.add("Vajpayee")
list[1] = "Modi"
for (element in list) { // Using individual elements (Objects)
println(element)
}
}
]]>
listOf
Inmutable, Fixed Size, Read ONLY
mutableListOf, arrayListOf, ArrayList
Mutable, READ and WRITE both, No Fixed Size
Map
<![CDATA[
// Map Tutorial: Key-Value pair
// var myMap = HashMap<Int, String>() // Mutable, READ and WRITE both, No Fixed Size
// var myMap = mutableMapOf<Int, String>() // Mutable, READ and WRITE both, No Fixed Size
var myMap = hashMapOf<Int, String>() // Mutable, READ and WRITE both, No Fixed Size
myMap.put(4, "Yogi")
myMap.put(43, "Manmohan")
myMap.put(7, "Vajpayee")
myMap.put(43, "Modi")
for (key in myMap.keys) {
println("Element at $key = ${myMap[key]}") // myMap.get(key)
}
]]>
mapOf
Inmutable, Fixed Size, Read ONLY
HashMap, mutableMapOf, hashMapOf
Mutable, READ and WRITE both, No Fixed Size
Set
<![CDATA[
fun main(args: Array<String>) {
// "Set" contains unique elements
// "HashSet" also contains unique elements but sequence is not guaranteed in output
var mySet = mutableSetOf<Int>( 2, 54, 3, 1, 0, 9, 9, 9, 8) // Mutable Set, READ and WRITE both
// var mySet = hashSetOf<Int>( 2, 54, 3, 1, 0, 9, 9, 9, 8) // Mutable Set, READ and WRITE both
mySet.remove(54)
mySet.add(100)
for (element in mySet) {
println(element)
}
}
]]>
setOf -> contains unique elements
Inmutable, Fixed Size, Read ONLY
Set -> contains unique elements
HashSet -> also contains unique elements but sequence is not guaranteed in output
Mutable, READ and WRITE both, No Fixed Size