Frequency of Words using HashMap

 package JavaPracticeInterview;

import java.util.HashMap;

import java.util.Map;

import java.util.Map.Entry;

import java.util.Set;

public class Frequency_of_Words {

public static void main(String[] args) {

// TODO Auto-generated method stub

String str ="Hello I am a programmer I am a hello";

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

Map<String, Integer> map = new HashMap<String, Integer>();

for(String s: words) {

Integer count = map.get(s);

if(count==null) {

map.put(s, 1);

}

else  {

map.put(s, ++count);

}

}

Set<Entry<String, Integer>> entrySet = map.entrySet();

for(Entry<String, Integer> entry: entrySet) {

if(entry.getValue()>0) {

System.out.println(entry.getKey() + " " + entry.getValue());

}

}

}

}

o/p:

a 2

Hello 1

programmer 1

I 2

hello 1

am 2