What I am doing here is in one class reading in a file where the first line contains info about the number of rows and columns in a grid to be made in a GUI representation. I made the first class read in the file, and returns a value "e" that I'm trying to pass into the GUI class to make the grid. I'm stuck on this as I've tried to make one class a super, and still can't figure it out.

 * @author unrealj
 * Battleship.java reads in a file defined by the text file 
 * "textfile.txt" and should return a value for the number
 * of rows and columns of the grid, and eventually an arraylist
 * of the ships, designated by the second and or more lines.
import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.FileInputStream;
import java.io.FileReader;
import java.io.InputStreamReader;
import java.io.LineNumberReader;

public abstract class BattleShip extends Board {
	private int e;
	private int se;
	public BattleShip(int e){
		this.e = e;
	public double getE(){
		//Allows the interest to be used by SuperClass
		return e;
		   public static void main(String args[])
		    // Open the file that is the first 
		    // command line parameter
		    FileInputStream fstream = new FileInputStream("textfile.txt");
		    // Get the object of DataInputStream
		    DataInputStream in = new DataInputStream(fstream);
		        BufferedReader br = new BufferedReader(new InputStreamReader(in));
		    String strLine;
		    //Read File Line By Line
		    FileReader fr = new FileReader("textfile.txt");
		    LineNumberReader ln = new LineNumberReader(fr);

		    while (ln.getLineNumber() == 0){

		    String s = ln.readLine();
		    int e = Integer.parseInt(s);


		   while ((strLine = br.readLine()) != null)   {
		      // Print the content on the console
		      System.out.println (strLine);
		    //Close the input stream
		    }catch (Exception e){//Catch exception if any
		      System.err.println("Error: " + e.getMessage());

Here is Board.java

 * @author unrealj
 * Board.java takes in a value from BS.java and
 * creates a GUI grid from it, and creates buttons based on e.
 * The cheat button will show where items in the arraylist are,
 * while the reset button will bring all buttons back to state
 * before the cheat button was placed.

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import java.util.ArrayList;
import javax.swing.*;

public abstract class Board extends JFrame {
    static ArrayList row = new ArrayList();
    static ArrayList column = new ArrayList();

	public Board(int e) {
        // Set the border layout for the frame
        setLayout(new BorderLayout());

     // Create panel1 for the button and
        // use a grid layout
        JPanel panel1 = new JPanel();
        panel1.setLayout(new GridLayout(e,e));
     // create ButtonListener
        ButtonListener listener = new ButtonListener();
        // Add buttons to the panel
        for (int i=1; i<(e*e); i++) {
        		JButton button = new JButton("" + "X" );

        // Create panel2 to hold a text field and panel1
        JPanel panel2 = new JPanel(new BorderLayout());
        panel2.setLayout(new GridLayout(1,2));
        JButton cheat = new JButton("CHEAT");
        JButton resume = new JButton("RESUME");
        add(panel2, BorderLayout.SOUTH);


        // Add panel2 and a button to the frame
        add(panel1, BorderLayout.CENTER);

        // set frame appearance
        setTitle("Battle them Ships!");
        setSize(400, 250);
        setLocation(100, 100);
    } // Board

    class ButtonListener implements ActionListener {
        public void actionPerformed(ActionEvent r) {
        	if (((Component) r.getSource()).getBackground()==Color.WHITE){
        		((Component) r.getSource()).setBackground(Color.BLACK);	
        	else if(((Component) r.getSource()).getBackground()==Color.BLACK){
        		((Component) r.getSource()).setBackground(Color.WHITE);

For tests sake, textfile.txt is

1 2 3 2

Thank you for your help.

Here's an overview of the norml way to structure this kind of code. You already have most of the bits, but in the wrong order!

Make BattleShip a non-abstract class so you can create an instance of it. Don't extend anything, just let it be what it is - the data for a BattleShips game.
Move all the code from main into the constructor for BatteleShip.
Replace what's currently in main with a simple
BattleShip bs = new BattleShip();
Now you have a fully-initialised instance of BattleShip.

In the Board class have an instance variable that references an instance of BattleShip - so methods in the Board class can call methods in the BattleShip game class to query all the values. Pass that instance as a parameter to Board's constructor (instead of int e).

Finally add a second line to main so it now reads:

BattleShip bs = new BattleShip(); // create and initialise a game
new Board(bs); // create a GUI using that game

That's a few steps, but all easy.

Thanks! I got it, I tried to implement the Super, then realized that I never initialized the Board in the main class, and then deleted all the abstract classes.

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