Question

WordFrequencies.java

1. Prepare a text file that contains text to analyze. It could be song lyrics to your favorite song.

2. With your code, you’ll read from the text file and capture the data into a data structure.

3. Using a data structure, write the code to count the appearance of each unique word in the lyrics.

4. Print out a word frequency list.

Example output of the word frequency list:

100: frog

94: dog

43: cog

20: bog

use bufferreader and comment the code

Answer 1

Program:

Output:

Sample Input File contents:

Code for the above screenshot:

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

public class Solution {
public static void main(String []args){
Scanner s = new Scanner(System.in);
//System.out.print("Enter a filename: "); //To make it dynamic by user input file name
String fileName = "input.txt"; //s.nextLine();
  
//Use the below code to find the current directory u are in which will make it easy for your to locate the Student file to run.
//System.out.println(System.getProperty("user.dir"));   
  
countWords(System.getProperty("user.dir"),fileName);
}
  
public static void countWords(String directory, String fileName) {
// Declare the HashMap
HashMap<String, Integer> wordCount = new HashMap();

// Puts together the string that the FileReader will refer to.
String fileNameWithDirectory = directory+ "\\src\\" + fileName;

try {
FileReader reader = new FileReader(fileNameWithDirectory);
BufferedReader br = new BufferedReader(reader);
// The BufferedReader reads the lines
  
String strCurrentLine;
while ((strCurrentLine = br.readLine()) != null) {
// First removes all non-letter characters, then to lowercase, then splits the input,
// \\s+ - matches sequence of one or more whitespace characters.
String[] words = strCurrentLine.replaceAll("[^a-zA-Z ]", "").toLowerCase().split("\\s+");
int freq = 0;

// for loop goes through every word
for (int i = 0; i < words.length; i++) {
// Case if the HashMap already contains the key.
// If so, just increments the value

if (wordCount.containsKey(words[i])) {
int n = wordCount.get(words[i]);
wordCount.put(words[i], ++n);
}
// Otherwise, puts the word into the HashMap
else {
wordCount.put(words[i], 1);
}
}
}
  
for (Map.Entry entry : wordCount.entrySet())
System.out.println(entry.getValue() + ": " + entry.getKey());
  
// Catching the file not found error
// and any other errors
}
catch (FileNotFoundException e) {
System.err.println("File not found.");
}
catch (NullPointerException e) {
System.err.println("File is empty.");
}
catch (Exception e) {
System.err.print(e);
}
}
}