Sort HashMap based on keys in Java

Firstly, create a HashMap −

HashMap hm = new HashMap();

Add some elements to the HashMap −

hm.put("Shirts", new Integer(700));
hm.put("Trousers", new Integer(600));
hm.put("Jeans", new Integer(1200));
hm.put("Android TV", new Integer(450));
hm.put("Air Purifiers", new Integer(300));
hm.put("Food Processors", new Integer(950));

Now, sort the HashMap based on keys using TreeMap −

Map<String, String> sort = new TreeMap<String, String>(hm);
System.out.println("Sorted Map based on key = "+sort);

The following is an example to sort HasMap based on keys −

Example

 Live Demo

import java.util.*;
public class Demo {
   public static void main(String args[]) {
      HashMap hm = new HashMap();
      hm.put("Shirts", new Integer(700));
      hm.put("Trousers", new Integer(600));
      hm.put("Jeans", new Integer(1200));
      hm.put("Android TV", new Integer(450));
      hm.put("Air Purifiers", new Integer(300));
      hm.put("Food Processors", new Integer(950));
      System.out.println("Map = "+hm);
      Map<String, String> sort = new TreeMap<String, String>(hm);
      System.out.println("Sorted Map based on key = "+sort);
   }
}

Output

Map = {Shirts=700, Food Processors=950, Air Purifiers=300, Jeans=1200, Android TV=450, Trousers=600}
Sorted Map based on key = {Air Purifiers=300, Android TV=450, Food Processors=950, Jeans=1200, Shirts=700, Trousers=600}