Write HashMap Programme to display basic functionaliy -After adding duplicate keys ,remove etc?

package com.JavaInterview.Programs;

import java.util.*;

/**
 * Find Out Factorial of a number
 * 
 * @author:http://javainterviewprograms.blogspot.in/
 * 
 */

public class HashmapTest {

 public static void main (String args[])

 {

  HashMap String,Integer> h= new HashMap String,Integer>();

 

  /*HashMap String,int> h= new HashMap String,int>();compiler error |You can't use

  primitive types as generic arguments in Java*/

  h.put("abc",12);

  h.put("bcd", 13);

 

  System.out.println("hashmap sample"+h);

 

  //adding duplicates keys

  h.put("abc",14);

  System.out.println("After adding duplicates key"+h);

 

  //adding duplicates value

  h.put("cdf",13);

  System.out.println("After adding duplicates value"+h);

 

  //adding duplicates keys again

  h.put("abc",15);

  System.out.println("Again after adding duplicates key"+h);

 

  //fetch by key

  System.out.println("Fetch map by its value"+h.get("abc"));

  System.out.println("Fetch map by its value"+h.get("bcd"));

 

  //HashMap Empty

  System.out.println("Is HashMap empty "+h.isEmpty());

 

  //remove elements

  h.remove("abc");

  System.out.println("After removal "+h);

 }

}

Output :

hashmap sample{abc=12, bcd=13}

After adding duplicates key{abc=14, bcd=13}

After adding duplicates value{abc=14, bcd=13, cdf=13}

Again after adding duplicates key{abc=15, bcd=13, cdf=13}

Fetch map by its value15

Fetch map by its value13

Is HashMap empty false

After removal {bcd=13, cdf=13}