Triangle Evaluation Based On Data Found In Text File

For an assignment I need to read an input text file and evaluate the triangle based on the data found in the text file which consists of an unknown number of groups of 3 numbers (Each group representing a different triangle). According to the project specifications I need to have a main method and several other methods. I have the main method set-up to receive data correctly but I am confused as to how I would get the values out of the text file and use them in the main method. For example, if I were to call the computePerimeter method in my main method, how would I make sure I get the correct perimeter for the given data?

Here is the code I have so far:

import java.io.*;
import java.util.Scanner;
public class TriangleEvaluator
{
public static void main(String[] args) throws FileNotFoundException
{
Scanner in = new Scanner(new File("triangleData.txt"));
double s1;
double s2;
double s3;
while (in.hasNextDouble())

[Code] ....