Java Collection Tutorial - Java NavigableMap.headMap(K toKey)


NavigableMap.headMap(K toKey) has the following syntax.

SortedMap < K , V > headMap(K toKey)


In the following code shows how to use NavigableMap.headMap(K toKey) method.

/*ww w . j  av  a 2  s. c o m*/
import java.util.NavigableMap;
import java.util.TreeMap;

public class Main {
  public static void main(String[] args) {
    NavigableMap<Integer, String> map = new TreeMap<Integer, String>();
    map.put(2, "two");
    map.put(1, "one");
    map.put(3, "three");
    System.out.println( map.headMap(1) + "\n");


The code above generates the following result.