Java HashMap replaceAll()

Java HashMap [Java HashMap] Java HashMap

replaceAll() hashMap

replaceAll() 

hashmap.replaceAll(Bifunction<K, V> function)

hashmap HashMap

  • function -

HashMap

replaceAll()

import java.util.HashMap;

class Main {
    public static void main(String[] args) {
        // HashMap
        HashMap<Integer, String> sites = new HashMap<>();

        // HashMap
        sites.put(1, "Google");
        sites.put(2, "Runoob");
        sites.put(3, "Taobao");
        System.out.println("sites HashMap: " + sites);

        //
        sites.replaceAll((key, value) -> value.toUpperCase());
        System.out.println("Updated HashMap: " + sites);
    }
}

sites HashMap: {1=Google, 2=Runoob, 3=Taobao}
Updated HashMap: {1=GOOGLE, 2=RUNOOB, 3=TAOBAO}

(key, value) -> value.toUpperCase() lambda HashMap Java Lambda

import java.util.HashMap;

class Main {
    public static void main(String[] args) {
        // HashMap
        HashMap<Integer, Integer> numbers = new HashMap<>();

        // iHashMap
        numbers.put(5, 0);
        numbers.put(8, 1);
        numbers.put(9, 2);
        System.out.println("HashMap: " + numbers);

        // key
        numbers.replaceAll((key, value) -> key * key);;
        System.out.println("Updated HashMap: " + numbers);
    }
}

HashMap: {5=0, 8=1, 9=2}
Updated HashMap: {5=25, 8=64, 9=81}

Java HashMap [Java HashMap] Java HashMap