Program: How to get all keys from Hashtable?

Below example shows how to get list of keys. keySet() method returns Set object will all keys.

package com.java2novice.hashtable;

import java.util.Hashtable;
import java.util.Set;

public class MyHashtableKeys {

	public static void main(String a[]){
		Hashtable<String, String> hm = new Hashtable<String, String>();
		//add key-value pair to Hashtable
		hm.put("first", "FIRST INSERTED");
		hm.put("second", "SECOND INSERTED");
		hm.put("third","THIRD INSERTED");
		System.out.println(hm);
		Set<String> keys = hm.keySet();
		for(String key: keys){
			System.out.println(key);
		}
	}
}

{third=THIRD INSERTED, second=SECOND INSERTED, first=FIRST INSERTED}
third
second
first