Count Characters

import java.util.Map;
import java.util.HashMap;
class Main {
    public static void main(String[] args) {
        countChar("banana");
    }
    public static void countChar(String s){
        Map<Character, Integer> charMap = new HashMap<>();
        for(char a : s.toCharArray()){
            if(!charMap.containsKey(a)){
                charMap.put(a,1);
            }
            else{
                charMap.put(a, charMap.get(a) + 1);
            }
        }
        System.out.println(charMap.toString());
    }
}