We can use the remove method to remove an entry from the HashMap.
fun remove(key: K): V?
The key of the entry to be removed from the HashMap is passed as an argument.
If the HashMap contains an entry for the provided argument then the value of the entry is returned. Otherwise, null is returned.
The code below demonstrates how to remove an entry from the HashMap:
fun main() {//create a new LinkedHashMap which can have String type as key, and int type as valuevar map : HashMap<String, Int> = HashMap<String, Int> ()// add two entriesmap.put("one", 1)map.put("two", 2)map.put("three", 3)println("The map is : $map")var oldValue = map.remove("one");println("\nmap.remove('one') : ${oldValue}")println("The map is : $map")oldValue = map.remove("four");println("\nmap.remove('four') : ${oldValue}")println("The map is : $map")}
Line 3: We create a new HashMap object with the name map.
Lines 5 to 7: We add three entries to the map {one=1,two=2,three=3}, using the put method.
Line 11: We use the remove method with one as an argument. This method checks for the entry with the key one. In our map, there is one entry with a key - one so that entry is removed and the value associated with the key is returned. Now the map is {two=2, three=3}.
Line 15: We use the remove method with four as an argument. This method checks for the entry with the key four. In our map, there is no entry with a key four. So null is returned. The map remains unchanged.