find element in java hashmap

/**
 * @author lautturi.com 
 * Java example: java search value in a hashmap 
 */

import java.util.*;
import java.util.concurrent.ConcurrentHashMap;

public class Lautturi {

	public static void main(String[] args){
		
		ConcurrentHashMap<String, Integer> numbers = new ConcurrentHashMap<>();
        numbers.put("One", 1);
        numbers.put("Two", 2);
        numbers.put("Three", 3);
        System.out.println("ConcurrentHashMap: " + numbers);

        // Using search()
        String key = numbers.search(4, (k, v) -> {return v == 3 ? k: null;});
        System.out.println("Searched value: " + key);
	}
}

output:

ConcurrentHashMap: {One=1, Two=2, Three=3}
Searched value: Three