HashMap

Question

what we can achieve using getOrDefault method ? This question arises so many times in my mind and i have searched a lot on google but unable to understand it properly. so please explain it to me ....!

Map<Long, Integer> map = new HashMap<>();
for (long num : nums) {
map.put(num, map.getOrDefault(num, 0) + 1);
}

Answer 1

getOrDefault method returns provided default value if key doesn't match in Map.

if num not exist in nums then 0 will be return

Answer 2

getOrDefault method have two param,
- the Key searched, if exists return value of this key
- default value, if Key searched don't be find return default value

Exemple :

HashMap<String, Integer> map
= new HashMap<>();
map.put("a", 100);
map.put("b", 200);
map.put("c", 300);
map.put("d", 400);

int exOne = map.getOrDefault("b", 500); // exOne = 200
int exTwo = map.getOrDefault("y", 500); //.exTwo = 500

Answer 3

I thought you got it figured out ...

https://www.sololearn.com/Discuss/3072359/?ref=app

Answer 4

Ipang i forgot it 🙂