Beginning programmer: i need help its cake for some of you

Question

ok i have an assignment :
hypothetically i have been given a data file that contains a letter(a,b,or c) and a number separated by a space it tellsme to create a program that will output the average each class of numbers (those w/ an 'a' on the same line, those w/ a 'b' etc etc.... this is all i have been able to get so far.... i'm trying to get this program to work so that it will print me all the numbers and letters on each line so that i know i can separate the info...... any help would be greatly appreciated
import java.io.*;
import java.util.StringTokenizer;
import java.lang.String;
public class HW2
     public static void main(String [] args)throws IOException
          BufferedReader br;
          br= new BufferedReader(new FileReader("filename"));
          String str= br.readLine();
          StringTokenizer st= new StringTokenizer(str);
          char c= st.nextToken.charAt(0);
          while (st.hasMoreTokens())
               System.out.println(st.nextToken());
}

Answer 1

So you need to loop over each line in the file?
You are almost there, the standard code is like this
BufferedReader br = new BufferedReader(new FileReader("filename"));
String str;
// for each line in the file
while ((str = br.readLine()) != null){
  // process the line
  System.out.println(str); 
br.close();Replace the "process the line" comment with code that you do for each line.
Good luck,
evnafets