/**
 * FileScanner.java
 *
 * @author Jeff Ondich
 * @version 2/18/10
 *
 * Illustrates the use of Scanner and File to read through
 * a file one line at a time, parsing each line as we go.
 *
 * We assume that the text file specified as the single
 * command-line argument consists of lines like this:
 *
 *    Susan 1968
 *    Bob 1945
 *    Esme 2003
 *
 * etc.  That is, a line plus a year.
 */

import java.util.*;
import java.io.*;

public class FileScanner
{
    public static void main(String[] args) throws IOException
    {
        if( args.length != 1 )
        {
            System.out.println("Usage: java FileScanner filetoscan");
            System.exit(1);
        }

        // Read the file one line at a time using fileScanner.
        String fileName = args[0];
        Scanner fileScanner = new Scanner(new File(fileName));
        while( fileScanner.hasNextLine() )
        {
            String line = fileScanner.nextLine();

            // For each line, extract the name and the year-of-birth.
            Scanner lineScanner = new Scanner(line);
            String name = "";
            if( lineScanner.hasNext() )
                name = lineScanner.next();

            int yearOfBirth = 0;
            if( lineScanner.hasNextInt() )
                yearOfBirth = lineScanner.nextInt();
            int age = 2009 - yearOfBirth; // Not a very robust program!

            System.out.println(name + " is " + age + " years old, more or less.");
        }
    } 
}