Java program to count number of duplicate words in given string

Program

package com.candidjava;

import java.util.HashMap;
import java.util.Set;

public class CountDuplicateWords
{

	static void duplicateWords(String inputString)
	{
		// Splitting inputString into words

		String[] words = inputString.split(" ");

		// Creating one HashMap with words as key and their count as value

		HashMap<String, Integer> wordCount = new HashMap<String, Integer>();

		// Checking each word

		for (String word : words)
		{
			// whether it is present in wordCount

			if (wordCount.containsKey(word.toLowerCase()))
			{
				// If it is present, incrementing it's count by 1

				wordCount.put(word.toLowerCase(), wordCount.get(word.toLowerCase()) + 1);
			}
			else
			{
				// If it is not present, put that word into wordCount with 1 as
				// it's value

				wordCount.put(word.toLowerCase(), 1);
			}
		}

		// Extracting all keys of wordCount

		Set<String> wordsInString = wordCount.keySet();

		// Iterating through all words in wordCount

		for (String word : wordsInString)
		{
			// if word count is greater than 1

			if (wordCount.get(word) > 1)
			{
				// Printing that word and it's count

				System.out.println(word + " : " + wordCount.get(word));
			}
		}
	}

	public static void main(String[] args)
	{
		duplicateWords("Bread butter and bread");

		duplicateWords("Java is java again java");

		duplicateWords("Super Man Bat Man Spider Man");
	}
}

Output

bread : 2

java : 3

man : 3

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