How to open a txt file and read numbers in Java

Question

How can I open a .txt file and read numbers separated by enters or spaces into an array list?

Answer 1

import java.io.*;  
public class DataStreamExample {  
     public static void main(String args[]){    
          try{    
            FileWriter  fin=new FileWriter("testout.txt");    
            BufferedWriter d = new BufferedWriter(fin);
            int a[] = new int[3];
            a[0]=1;
            a[1]=22;
            a[2]=3;
            String s="";
            for(int i=0;i<3;i++)
            {
                s=Integer.toString(a[i]);
                d.write(s);
                d.newLine();
            }

            System.out.println("Success");
            d.close();
            fin.close();    



            FileReader in=new FileReader("testout.txt");
            BufferedReader br=new BufferedReader(in);
            String i="";
            int sum=0;
            while ((i=br.readLine())!= null)
            {
                sum += Integer.parseInt(i);
            }
            System.out.println(sum);
          }catch(Exception e){System.out.println(e);}    
         }    
        }  

OUTPUT:: Success 26

Also, I used array to make it simple.... you can directly take integer input and convert it into string and send it to file. input-convert-Write-Process... its that simple.