Java File I/O project

Question

Ok so im taking intermediate java and I remember nil from intro to java. I've got to make a program that reads a text file (the file was provided by the professor), then Ive got to use the stingtokenizer method to break the the file into pieces (using , as the delimiter). Then I have to output to the screen and to a file each student and their information (the file is a list of students and their classes). Theres actually a little more than that but right now thats all im concerned with...got to take it one step at a time.
Right now Im building the read method for my class which should find the file, read the file, and then tokenize it. This is what Ive got so far, but I dont know what to put as a return value I need help understanding the concept of what Im doing.
package homework1;
* @author Joseph Weaver
import java.util.*;
import java.io.*;
public class Inforetrieval {
    public String ReadFile()throws IOException {
        BufferedReader input = new BufferedReader(new FileReader("students.txt"));
        String studentinfo;
        while ((studentinfo = input.readLine()) != null) {
            StringTokenizer line = new StringTokenizer(studentinfo);
            while (line.hasMoreTokens()) {
                System.out.println(line.nextToken());
        input.close();
        return;
}

Answer 1

Does your tokenizer work the way you want it to? It looks like you've got printing to the screen, so you're concerned with writing to a file?
First of all you need to know what exactly you're going to write to a file. Since you're reading from a file it would probably make sense that the files your program generates (writes to) will be formatted differently. One file per student? Figure out or decide what you want to write to a file.
Next, you need to decide what your method ReadFile() should do. It looks like its doing several perhaps unrelated things - not only is it reading a file, but it's also tokenizing the file and printing to the screen. Would you expect a method named ReadFile() to do all that?
I suggest breaking your logic into several methods. Your methods should perform only one thing. Once you've separated your logic into several small methods, it should be clear what their return values should be.
Once you've done this, you could take the results from the tokenize method and pass them on to a method that will print the tokens to the screen and and to a method that will write the tokens to a file.
As you said, there's more to the assignment but this is the part you're working on now. If you divide the logic into methods as suggested, later on if you need to tokenize something or write something to a file, you'll have already written methods to do that.
Or, you could put everything into the main() class and get the assignment done quickly.