public TreeMap()

public TreeMap()

Constructs a new, empty tree map, using the natural ordering of its keys. All the keys inserted into the TreeMap must implements the Comparable interface.

import java.util.*;

class TreeMapConstructor1{
 public static void main(String args[]){
  TreeMap<Integer, String> myMap;
  myMap = new TreeMap<> ();
  
  /* Insert data to myMap */
  myMap.put(1, "a");
  myMap.put(7, "d");
  myMap.put(2, "b");
  myMap.put(6, "d");
  myMap.put(3, "c");
  myMap.put(5, "d");
  myMap.put(4, "d");
  
  System.out.println("Elements in myMap are");
  System.out.println(myMap);  
 }
}

Output

Elements in myMap are
{1=a, 2=b, 3=c, 4=d, 5=d, 6=d, 7=d}

As you observe the output, TreeMap prints the output in natural ordering of the key, which is integer here.

Prevoius                                                 Next                                                 Home