Read index and strings from text file Java

Question

Suppose i have a text file that has a number code and a string label on each line:

0102 Apple Banana Code
0203 Pear Watch Time
0405 Java Computer Pen
0607 Car Bike Drive

How could i print the sum of the non zero numbers in the front and the first two words of each line? Assuming that the numbers are always 4 digits and words are separated by a single space from the number and in between the words. For example I would get:

3 Apple Banana 
5 Pear Watch 
9 Java Computer 
13 Car Bike

I have tried to initialize this but i have no idea where to go from here

FileReader fr = new FileReader(fileName);
BufferedReader inFile = new BufferedReader(fr);
String[][] words = new String[100][];
String line;
int size = 0;
while((line = inFile.readLine()) != null) {
    words[size++] = line.split(" ");
}
inFile.close();

You can use `Intstream`. Please check https://stackoverflow.com/a/67609220/4347350 — karacaoglanb, Apr 30 '22 at 14:54

score 0 · Answer 1 · answered Apr 30 '22 at 19:01

You are close. Refer to below code. Explanations appear after the code.

import java.io.BufferedReader;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;

public class Tester {
    private static void handleLine(String line) {
        String[] parts = line.split(" ");
        int num = handleNumber(parts[0]);
        System.out.printf("%d %s %s%n", num, parts[1], parts[2]);
    }

    private static int handleNumber(String number) {
        char[] digits = number.toCharArray();
        int total = 0;
        for (char digit : digits) {
            total += digit - '0';
        }
        return total;
    }

    public static void main(String[] args) {
        Path path = Path.of("tragedy.txt");
        try (BufferedReader inFile = Files.newBufferedReader(path)) {
            String line = inFile.readLine();
            while (line != null) {
                handleLine(line);
                line = inFile.readLine();
            }
        }
        catch (IOException xIo) {
            xIo.printStackTrace();
        }
    }
}

I use class Files to create a BufferedReader but it is not required. Your code for obtaining a BufferedReader is correct.
I also use try-with-resources to ensure that the file is closed.
You asked how to print the file lines after manipulating them slightly so that is what the above code does.
char is actually a number so to get the actual number value from the char, I subtract the value of the 0 character.

Read index and strings from text file Java

1 Answers1