Reading Numbers from a Text File : File Reader « File Input Output « Java

Reading Numbers from a Text File


// The buffering makes the program more than 20 times faster.
public class SumFile {

  public static void main(String[] a) throws IOException {

  static void sumfile(String filename) throws IOException {
    Reader r = new BufferedReader(new FileReader(filename));
    StreamTokenizer stok = new StreamTokenizer(r);
    double sum = 0;
    while (stok.ttype != StreamTokenizer.TT_EOF) {
      if (stok.ttype == StreamTokenizer.TT_NUMBER)
        sum += stok.nval;
        System.out.println("Nonnumber: " + stok.sval);
    System.out.println("The file sum is " + sum);


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