//------------
// Introduction to Programming Using Java: An Object-Oriented Approach
//	Arnow/Weiss
//------------
import java.awt.*;
import java.awt.event.*;
import java.applet.*;

class LifeDisplay extends Canvas {
    LifeDisplay() {
        setBackground(new Color(0,210,90));
    }
    void displayWorld(boolean [][] world) {
        this.world = world;
        Graphics g = this.getGraphics();
        paintBackground(g);
        paintWorld(g);
    }
    public void update(Graphics g) {
        paintBorder(g);
        paintBackground(g);
        paintWorld(g);
    }
    private void paintBackground(Graphics g) {
        g.setColor(new Color(240,210,0));
        g.fillRect(5,5,this.getSize().
                       width-10,this.getSize().height-10);
    }
    private void paintBorder(Graphics g) {
        g.setColor(new Color(0,0,0));
        g.fillRect(0,0,this.getSize().width,5);
        g.fillRect(0,this.getSize().
                       height-5,this.getSize().width,5);
        g.fillRect(0,0,5,this.getSize().height);
        g.fillRect(this.getSize().
                       width-5,0,5,this.getSize().height);
    }
    private void paintWorld(Graphics g) {
        g.setColor(new Color(30,20,120));
        if (world != null)
           for (int i = 0; i < world.length; i++)
               for (int j = 0; j < world[i].length; j++)
                   paint1Square(g,i,j);
    }
    private void paint1Square(Graphics g, int i, int j) {
        if (world[i][j])
           g.fillRect(5+i*CellWidth, 5+j*CellWidth, 
                      CellWidth, CellWidth);
    }
    boolean[][]        world = null;
    static final int   CellWidth = 3;
}