Java - Sum Numbers From Text File

  1. HOME
  2. Java
  3. File Input Output
  4. Readers and Writers

Description

Sum Numbers From Text File

Demo

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;

public class Main {

  public static void main(String[] args) {

    String fileName = "input.txt";

    try (BufferedReader fileReader = new BufferedReader(new FileReader(fileName));) {
      long sum = 0;

      while (true) {
        String lineRead = fileReader.readLine();
        if (lineRead == null) {
          // End of file is reached
          break;//w  w w.  j ava  2 s.  com
        }
        long num = Integer.parseInt(lineRead);
        sum += num;
      }// end of while

      System.out.println(sum);
    }// end of try block

    catch (IOException ioex) {
      System.err.println("Error");
    }// end of catch block
  }// end of main
}// end of class

Related Exercise