Java Code to read 3 NUMBERS from each line from a text file into a 2 dimensional

Question

Java Code to read 3 NUMBERS from each line from a text file into a 2 dimensional array and output the multipication value of each line into a new text file

EXAMPLE

INPUT TEXT FILE

1 2 5

3 1 5

...........(Text File should be theoretically infinite)

OUTPUT TEXT FILE

Area for Line 1 is = 10

Area for Line 2 is = 15

.........(Until the Area of the Last line in the text file has been determined)

This should be implemented in a menu driven system LOOP eg

1) Prompt User To Enter Filename

2) Exit Loop

............

Explanation / Answer

Java Program:

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.Scanner;

public class Multiplier {

   public static void main(String args[]) throws IOException {

       int choice;

       // Creating a Scanner instance to take inputs from the user
       Scanner scanner = new Scanner(System.in);
       System.out.println("1) Prompt User To Enter Filename 2) Exit Loop ");
       choice = scanner.nextInt();
       do {
           System.out.println("Provide the path of the input file: ");

           // Input the filename from user
           String filename = scanner.next();
           FileInputStream fis = null;
           BufferedReader reader = null;
           try {
               fis = new FileInputStream(filename);
               reader = new BufferedReader(new InputStreamReader(fis));
           } catch (FileNotFoundException e) {
               throw new RuntimeException(
                       "Did not find the input file. Please provide a valid path name for the input file");
           }
           PrintWriter out;
           System.out.println("Provide the path of the output file: ");

           // Input the output filename from user
           filename = scanner.next();
           out = new PrintWriter(filename);

           String line = null;
           String[] values;
           // Reading each line of file
           while ((line = reader.readLine()) != null) {
               // Split each line to get values
               values = line.split(" ");
               int sum = 1;
               for (int i = 0; i < values.length; i++) {
                   // Convert string to int and perform multiplication
                   sum = sum * Integer.parseInt(values[i]);
               }
               // Write sum to the output file
               out.println(sum);
           }
           fis.close();
           reader.close();
           out.close();
           System.out
                   .println("1) Prompt User To Enter Filename 2) Exit Loop ");
           choice = scanner.nextInt();
       } while (choice != 2);
       scanner.close();
   }

}

--------------------------------------------------------------------------------------------------------------------

Sample Output:

1) Prompt User To Enter Filename
2) Exit Loop

1
Provide the path of the input file:
C:\test\input.txt
Provide the path of the output file:
C:\test\output.txt
1) Prompt User To Enter Filename
2) Exit Loop

2

----------------------------------------------------------------------------------------------------

input.txt:

55 2 33
1 2 3
4 6 10
10 10 10
1 2 -3
8 2 0

output.txt:

3630
6
240
1000
-6
0

Related Questions

Navigate

• Browse (All)
• Browse J
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.