Prog3AssignmentGameOfLife/src/Life.java

import java.util.Arrays;

public class Life implements ILife {

    static String[] board = new String[]{   "*    ",
                                            "*    ",
                                            "*    ",
                                            "     ",
                                            "     " };

    public static void main(String[] args) {
        Life l = new Life(board);
        l = (Life) l.nextGeneration();
    }

    public Life() {
        nukeAll();
    }

    public Life(String[] setup) {
        this();
        for (int y = 0; y < setup.length; y++){
            for (int x = 0; x < setup[y].length(); x++){
                if (setup[y].charAt(x) != ' '){
                    setAlive(x, y);
                }
            }
        }
        printTable(board);
    }

    private void printTable(String[] board) {
        for(int i = 0; i < board.length; i++) System.out.println(Arrays.toString(new String[]{board[i]}));
        System.out.println("________");
    }

    @Override
    public void nukeAll() {    //works
        // TODO Auto-generated method stub
        for (int y = 0; y < board.length; y++){
            for (int x = 0; x < board[y].length(); x++) {
                setDead(x, y);
            }
        }
    }

    @Override
    public void setAlive(int x, int y) {
        // TODO Auto-generated method stub
        board[y] = board[y].substring(0, x) + '*' + board[y].substring(x+1);
    }

    @Override
    public void setDead(int x, int y) {
        // TODO Auto-generated method stub
        board[y] = board[y].substring(0, x) + ' ' + board[y].substring(x+1);
    }

    @Override
    public boolean isAlive(int x, int y) {
        if(board[y].charAt(x) == '*'){
            return true;
        }
        else{
            return false;
        }
    }

    @Override
    public ILife nextGeneration() {

        int alive;
        String[] nextBoard = new String[]{  "     ",
                                            "     ",
                                            "     ",
                                            "     ",
                                            "     " };

        for (int y = 0; y < board.length; y++){
            for (int x = 0; x < board[y].length(); x++){
                alive=aliveNeighbours(x,y);

                //A new Cell is born
                if(!isAlive(x,y) && alive == 3) {
                    nextBoard[y] = nextBoard[y].substring(0, x) + '*' + nextBoard[y].substring(x+1);
                }
                //Cell is lonely and dies or cell is overpopulated and dies
                else if((isAlive(x,y) && (alive < 2)) || (alive > 3)){
                    nextBoard[y] = nextBoard[y].substring(0, x) + ' ' + nextBoard[y].substring(x+1);
                }
                //Cell with two or three living neighbours lives on
                else if(isAlive(x,y) && (alive == 2 || alive == 3)){
                    nextBoard[y] = nextBoard[y].substring(0, x) + board[y].charAt(x) + nextBoard[y].substring(x+1);
                }
            }
        }
        board = nextBoard;
        System.out.println("next Generation");
        printTable(board);
        return null;
    }

    private int aliveNeighbours(int x, int y) {
        int neighbours = 0;

        if(x>0 && y>0){
            if(board[y-1].charAt(x-1) == '*'){
                neighbours++;
            }
        }
        if(x>0){
            if(board[y].charAt(x-1) == '*'){
                neighbours++;
            }
            if(y<4 ){
                if(board[y+1].charAt(x-1) == '*'){
                    neighbours++;
                }
            }
        }

        if(y>0){
            if(board[y-1].charAt(x) == '*'){
                neighbours++;
            }
            if(x<4){
                if(board[y-1].charAt(x+1) == '*'){
                    neighbours++;
                }
            }
        }

        if(x<4){
            if(board[y].charAt(x+1) == '*'){
                neighbours++;
            }
        }
        if(y<4){
            if(board[y+1].charAt(x) == '*'){
                neighbours++;
            }
        }
        if(x<4 && y<4){
            if(board[y+1].charAt(x+1) == '*'){
                neighbours++;
            }
        }
        return neighbours;
    }
}