Question

Create a file with a 20 lines of text and name it "lines.txt". Write a program to read this a file "lines.txt" and write the text to a new file, "numbered_lines.txt", that will also have line numbers at the beginning of each line. Example: Input file: "lines.txt" Line one Line two Expected output file: 1 Line one 2 Line two

Answer 1

Answer:

The code has been developed in JAVA as it is the best feasible concept to handle the files.

CODE :

import java.io.*;

public class textEditor { // main class that has the code

    public static void main(String[] args) { // main driver method

       try {

            int count = 0; // count to print the line numbers to the output file

           BufferedReader br = new BufferedReader(new FileReader("lines.txt")); // reading the data from the source text file

           File outfile = new File("numbered_lines.txt"); // creating a file in the output directory

           FileWriter fw = new FileWriter(outfile.getAbsoluteFile()); // initialising the filewriter class to write the data

           BufferedWriter bw = new BufferedWriter(fw); // appending the bufferedwriter to get the data to the output file

           String line; // temporary string value

       

           if (!outfile.exists()) { // if file doesnt exists, then create it

               outfile.createNewFile();

           }

         

           while ((line = br.readLine()) != null){ // iterating over the total line in the source file

               count++;

               bw.write(count +" "+ line); // writing the source data with the line numbers to the output file

               bw.write("\n");

           }        

           bw.close(); // closing the file

           System.out.println("Process Done"); // prompt for the user

       } catch (IOException e) { // catching if any exception is raised

           e.printStackTrace();

       }

   }

}

Explanation: