Java TreeMap get head sub map by key value

import java.util.SortedMap;
import java.util.TreeMap;

public class Main {

  public static void main(String[] args) {
    TreeMap<String, String> treeMap = new TreeMap<String,String>();
    treeMap.put("1", "CSS");
    treeMap.put("3", "Java");
    treeMap.put("2", "HTML");
    treeMap.put("5", "Five");
    treeMap.put("4", "Four");

    System.out.println(treeMap);/*  www. ja  v  a2s.  c  o  m*/
    
    SortedMap<String, String> sortedMap = treeMap.headMap("2");
    System.out.println(sortedMap);
  }
}