AreaSubtracting.java Source code

Introduction

Here is the source code for AreaSubtracting.java

Source

import java.awt.BasicStroke;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.geom.Area;
import java.awt.geom.Ellipse2D;
import java.awt.geom.GeneralPath;

import javax.swing.JFrame;
import javax.swing.JPanel;

public class AreaSubtracting extends JPanel {
    DrawingCanvas canvas;

    public AreaSubtracting() {
        canvas = new DrawingCanvas();
        add(canvas);

        canvas.area1 = new Area(canvas.gp);
        canvas.area1.subtract(canvas.area2);
        canvas.repaint();
    }

    public static void main(String arg[]) {
        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.getContentPane().add("Center", new AreaSubtracting());
        frame.pack();
        frame.setSize(new Dimension(400, 300));
        frame.setVisible(true);
    }

    class DrawingCanvas extends Canvas {
        GeneralPath gp;
        Ellipse2D ellipse;
        Area area1, area2;

        public DrawingCanvas() {
            setBackground(Color.white);
            setSize(350, 250); // width and height of canvas
            int w = getWidth();
            int h = getHeight();

            gp = new GeneralPath();
            gp.moveTo(w / 8, h / 2);
            gp.lineTo(w / 2, h / 4);
            gp.lineTo(7 * w / 8, h / 2);
            gp.lineTo(w / 2, 3 * h / 4);
            gp.closePath();
            area1 = new Area(gp); // General path area object

            ellipse = new Ellipse2D.Double(w / 4, h / 4, w / 2, h / 2);
            area2 = new Area(ellipse); // Ellipse area object
        }

        public void paint(Graphics g) {
            Graphics2D g2D = (Graphics2D) g;
            g2D.setStroke(new BasicStroke(2.0f));

            g2D.draw(area1);
            g2D.draw(area2);
        }

    }
}