Question

Map<Integer, String> map = new HashMap<Integer, String>();

How do I get the size/length of matching value’s at the String?

example:

1 , Red
2 , Red
3 , Blue
4 , Blue
5 , Red

Size of the String of RED = 3

Answer 1

Use .values() to get a collection containing all the values of the hash map, and then use Collections.frequency() to count the number of objects in the collection.

return Collections.frequency(map.values(), "red");