Get Head Map from TreeMap in Java

/* ww w .  j  a v  a2  s .  com*/
import java.util.Map;
import java.util.TreeMap;

public class Main {
  public static void main(String[] a) {

    TreeMap map = new TreeMap();
    map.put("key1", "value1");
    map.put("key2", "value2");
    map.put("key3", "value3");

    Map map2 = map.headMap("key2");
    System.out.println(map2);
  }
}