Find duplicate characters in String ?

package com.JavaInterview.Programs;

/**
 * Find Out Duplicate
 * 
 * @author:http://javainterviewprograms.blogspot.in/
 * 
 */

import java.util.*;

import java.util.HashMap;

import java.util.Set;

public class DuplicateCharacters {

 public void findDuplicate(String str)

 {

  char[] charc=str.toCharArray();

  Map<Character,Integer> mapc=new HashMap<Character,Integer>();

  for(Character ch:charc)

  {

   if(mapc.containsKey(ch))

   {

    mapc.put(ch,mapc.get(ch)+1);

   }

   else

   {

    mapc.put(ch,1);

   }

  }

  Set<Map.Entry<Character, Integer>> entrySet=mapc.entrySet();

  System.out.printf("list of duplicates characters in string '%s' %n",str);

  for(Map.Entry<Character, Integer> entry:entrySet)

  {

   if(entry.getValue()>1)

   {

    System.out.printf("%s:%d%n",entry.getKey(),entry.getValue());

   }

  }

 

 }

 public static void main(String args[])

 {

  Scanner input=new Scanner(System.in);

  System.out.println("Please enter the string to find out duplicate Characters :");

  String str=input.next();

  DuplicateCharacters dc=new DuplicateCharacters();

  dc.findDuplicate(str);

 }

}

Output:

Please enter the string to find out duplicate Characters :

papaya

list of duplicates characters in string 'papaya' 

a:3

p:2