public class Pair<K, V> {
    private K key;
    private V value;

    public Pair(K key, V value) {
        this.key = key;
        this.value = value;
    }

    public K getKey() {
        return this.key;
    }

    public V getValue() {
        return this.value;
    }

    public static void main(String[] args) {
        Pair<Integer, String> p1 = new Pair<>(123, "Generics");
        Integer key = p1.getKey();
        String value = p1.getValue();
        System.out.println("Key: " + key);
        System.out.println("Value: " + value);
    }
}