Flag.java

/*
    Class representing a U.S. flag from the 50's
    (when there were only 48 states).
    Illustrates while loops and use of private methods
    as helpers.
*/

import java.awt.*;
import objectdraw.*;

public class Flag {

    // number of stars per row and column
    private static final int NUM_ROWS_STARS = 6;
    private static final int NUM_COLS_STARS = 8;
    
    // size of stars (really circles!)
    private static final int STAR_DIAM = 6;

    // space btn start of successive stars
    private static final int STAR_JUMP = 8;

    // space btn edge of star field and first star
    private static final int OFFSET = 1;

    // dimensions of star field
    private static final int STAR_FIELD_WIDTH =
        NUM_COLS_STARS * STAR_JUMP+OFFSET;
    private static final int STAR_FIELD_HT =
        NUM_ROWS_STARS * STAR_JUMP+OFFSET;

    // dimensions of flag
    private static final double FLAG_WIDTH =
        2.5 * STAR_FIELD_WIDTH;
    private static final int FLAG_HT = STAR_FIELD_HT*13/7;

    // dimensions of stripes
    private static final double SHORT_STRIPE_WIDTH =
        FLAG_WIDTH - STAR_FIELD_WIDTH;
    private static final int STRIPE_HT = STAR_FIELD_HT/7;

    // number of red stripes of each sort in flag
    private static final int NUM_SHORT_STRIPES = 4;
    private static final int NUM_LONG_STRIPES = 3;

    private DrawingCanvas canvas;    // where to draw

    // Draw a flag at the coordinates point on theCanvas
    public Flag( Location point, DrawingCanvas theCanvas )
    {
        canvas = theCanvas;  // save canvas

        // draw short stripes
        drawStripes(point.getX() + STAR_FIELD_WIDTH,
                    point.getY(),
                    SHORT_STRIPE_WIDTH,
                    NUM_SHORT_STRIPES);

        // draw long stripes
        drawStripes(point.getX(),
                    point.getY()+2 * NUM_SHORT_STRIPES * STRIPE_HT,
                    FLAG_WIDTH+1,
                    NUM_LONG_STRIPES);

        // draw field of stars
        drawStars(point);

        // outline flag
        new FramedRect(point.getX()-1,
                       point.getY()-1,
                       FLAG_WIDTH+1,
                       FLAG_HT+1,
                       canvas);
    }

       // Draw numStripes red stripes starting at (x,y)

    // which are "width" pixels wide.
    private void drawStripes(double x, double y,
                             double width, int numStripes)
    {
        int stripeNum = 0;

        while (stripeNum < numStripes)
        {
             new FilledRect(x, y, width, STRIPE_HT, canvas).setColor(Color.red);
             stripeNum++;
             y = y + 2 * STRIPE_HT;
        }
     }

     // Draw blue background and stars, framed in black,
     // starting at point.
     private void drawStars(Location point)
     {
          // Draw and frame background
          new FilledRect(point, STAR_FIELD_WIDTH, STAR_FIELD_HT, 
                         cavas).setColor(Color.blue);

          new FramedRect(point.getX()-1, point.getY()-1,
                                           STAR_FIELD_WIDTH+1,
                                           STAR_FIELD_HT+1,
                                           canvas);
           int row = 0;
           int col;
           double x;
           double y = point.getY()+OFFSET;

           // draw stars
           while (row < NUM_ROWS_STARS)
           {
                col = 0;
                x = point.getX()+OFFSET;
                while (col < NUM_COLS_STARS)
                {
                      new FilledOval(x,y,STAR_DIAM,
                                     STAR_DIAM,canvas).setColor(Color.white);
                      col++;
                      x = x + STAR_JUMP;
                }
                y = y + STAR_JUMP;
                row++;
            }
     }

}

MakeFlags.java

import objectdraw.*;
import java.awt.*;

// program to draw a Flag upon mouse click.

public class MakeFlags extends WindowController {

    // draws a Flag with upper left at point of click
    public void onMouseClick( Location point )
    {
        new Flag(point, canvas);
    }
}