Java Collection Tutorial - Java TreeMap.headMap(K toKey, boolean inclusive)








Syntax

TreeMap.headMap(K toKey, boolean inclusive) has the following syntax.

public NavigableMap <K , V> headMap(K toKey,   boolean inclusive)

Example

In the following code shows how to use TreeMap.headMap(K toKey, boolean inclusive) method.

import java.util.NavigableMap;
import java.util.TreeMap;
/*from w ww  . j a  v  a 2  s . co  m*/
public class Main {
   public static void main(String[] args) {
      
      TreeMap<Integer, String>  treemap = new TreeMap<Integer, String> ();
      NavigableMap<Integer, String>  treemapheadincl = new TreeMap<Integer, String> ();
      
      // populating tree map
      treemap.put(2, "two");
      treemap.put(1, "one");
      treemap.put(3, "three");
      treemap.put(6, "six");
      treemap.put(5, "from java2s.com");
      
      // getting head map inclusive 3
      treemapheadincl=treemap.headMap(3,true);
      
      System.out.println("Checking values of the map");
      System.out.println("Value is: "+ treemapheadincl);
   }    
}

The code above generates the following result.