Sum from ArryList when scanning a file?

Question

Java

Good afternoon!
I've been struggling with this problem for three days now. I need to get the sum of the first column. The readable file has an entry like: " 1 Petya Pupkin". THOSE. let's say there will be 300 records with different numbers, and I will need to get the sum of these numbers (assuming that I read them from a file and records will be added to the file).
Example:
A .txt file contains
1 Petya Pupkin
15 Sashka Noviy
9 Bot Add
8 Serega Petrovich
Output SUM (33) (And Names and Surnames are discarded)
Here is the actual code that reads from the file and displays the entire file to the console:

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

    public class Main {
        String line;
        List<User> mass = new ArrayList<User>();

        public void reader(){
            BufferedReader readFromFile = null;
            try {
                readFromFile = new BufferedReader(new FileReader("src//1.txt"));
                while ((line = readFromFile.readLine())!=null){
                    User newUser = new User();
                    newUser.key = line;
                    mass.add(newUser);

                   //User newUser1 = new User();
                    //newUser1.chislo = Integer.parseInt(String.valueOf(newUser));
                    //mass.add(newUser1);
                }
            }catch (IOException e) {
                e.printStackTrace();
            }finally{

                if (readFromFile !=null)
                    try{
                        readFromFile.close();
                    }catch (IOException e) {
                        e.printStackTrace();
                    }

            }
        }

        public static void main(String[] args) throws IOException {
            Main test = new Main();
            test.reader();
            for (User newUser : test.mass)
                System.out.println(newUser.key);

            //Main test1 = new Main();
            //test1.reader();
            //for(User newUser1 : test1.mass)
                //System.out.println(newUser1.chislo);
        }

        private class User {
            public String key;
            public int chislo;
        }
    }

I don't know what to do anymore.

Answer 1

I'll expand bimeg's answer a bit and post the source code from the comments.

public class Reader {
  private List<User> users = new ArrayList<User>();

  public void read(String path) {
    BufferedReader readFromFile = null;
    try {
      readFromFile = new BufferedReader(new FileReader(path));
      String line = null;
      while ((line = readFromFile.readLine()) != null) {
        User newUser = new User(line);
        users.add(newUser);
      }
    } catch (IOException e) {
      e.printStackTrace();
    } finally {

      if (readFromFile != null)
        try {
          readFromFile.close();
        } catch (IOException e) {
          e.printStackTrace();
        }

    }
  }

  public int calculateSum() {
    int sum = 0;
    for (User user : users) {
      sum += user.getKey();
    }
    return sum;
  }

  private class User {
    public int key = 0;
    public String value;

    public User(String line) {
      if (line != null && !line.isEmpty()) {
        String[] entries = line.split("\\s", 2);
        this.key = Integer.valueOf(entries[0]); // можно завернуть в
                            // try {} catch
        this.value = entries[1];
      } else {
        // логируем
      }
    }

    public int getKey() {
      return key;
    }

    public String getValue() {
      return value;
    }
  }

  public static void main(String[] args) {
    Reader reader = new Reader();
    reader.read("src//1.txt");
    System.out.println(reader.calculateSum());
  }
}

Answer 2

private static class User {
    public final String key;
    public final int num;

    public User(String key) {
        this.key = key;
        num = Integer.parseInt(key.split("\\s")[0]);
    }
}