Java Hashmap get a list of keys

/**
 * @author lautturi.com 
 * Java example: get the keys from hashmap and put them into a list in java
 */

import java.util.*;

public class Lautturi {

	public static void main(String[] args) {

		Map<Integer, String> map = new HashMap<Integer, String>() {{
			put(5,"Apple");
			put(7,"Banana");
			put(12,"Cherry");
			put(33,"Orange");
			put(23,"Lautturi");
	    }};
	    
		List<Integer> list = new ArrayList<Integer>(map.keySet());

	    System.out.println("List of keys: " + list);
	
	}
}

output:

List of keys: [33, 5, 7, 23, 12]