HashMap Example Code

import java.util.HashMap;
import java.util.Map;
import java.util.Iterator;
import java.util.Set;

public class HashMapEx {
   public static void main(String args[]) {
      HashMap<Integer, String> hmap = new HashMap<Integer, String>();

      // Adding to HashMap
      hmap.put(12, "Kabir");
      hmap.put(2, "Ravi");
      hmap.put(7, "Luis");
      hmap.put(49, "Peter");
      hmap.put(3, "Aditya");

      // Iterate through HashMap
      Set set = hmap.entrySet();
      Iterator iterator = set.iterator();

      while(iterator.hasNext()) {
         Map.Entry mentry = (Map.Entry)iterator.next();
         System.out.print("Key is: "+ mentry.getKey() + " & Value is: ");
         System.out.println(mentry.getValue());
      }

      // Get a value based on key
      String val = hmap.get(2);
      System.out.println("Value for key 2 is: " + val);

      // Remove on the basis of key
      hmap.remove(3);
      System.out.println("Map after removal of key 3 is:");
      Set set2 = hmap.entrySet();
      Iterator iterator2 = set2.iterator();
      while(iterator2.hasNext()) {
          Map.Entry mentry2 = (Map.Entry)iterator2.next();
          System.out.print("Key is: "+mentry2.getKey() + " & Value is: ");
          System.out.println(mentry2.getValue());
      }
   }
}