Reading double values from a file

Question

I\'m trying to read some numbers (double) from a file and store them in an ArrayList and an array (yes, I need both) with the code below:

try {
    Scanner s         


        

Answer 1

Below is my rendition of your code, adapted to make it run. It immediately explodes with an array indexing exceptions.

So: Can you give us a little more framework? What's different from what I did?

import java.io.File;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Scanner;

public class Zenzen {

   private static ArrayList tmp = new ArrayList();

   private static File file = new File("Zenzen.dat");

   public static void main(String[] args) {

      Scanner scan;
      try {
         scan = new Scanner(file);
         Object[][] tmp2 = new Object[tmp.size() / 2][2];
         int tmp3 = 0;

         while (scan.hasNextDouble()) {
            tmp.add(scan.nextDouble());
            System.out.println(Arrays.deepToString(tmp.toArray())); // debug print
            for (int i = 0; i < tmp.size() / 2; i++) {
               for (int j = 0; j < 2; j++) {
                  tmp2[i][j] = tmp.get(tmp3);
                  tmp3++;
               }
            }
         }

      } catch (FileNotFoundException fnfe) {
         fnfe.printStackTrace();
      }
   }
}

---

[0.0]
[0.0, 0.0]
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 0
    at Zenzen.main(Zenzen.java:26)