TArea.java Source code

Introduction

Here is the source code for TArea.java

Source

import java.awt.BasicStroke;
import java.awt.BorderLayout;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Container;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.geom.Area;
import java.awt.geom.Ellipse2D;
import java.awt.geom.GeneralPath;

import javax.swing.ButtonGroup;
import javax.swing.JApplet;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JRadioButton;
import javax.swing.border.TitledBorder;

public class TArea extends JApplet implements ActionListener {
    DrawingCanvas canvas;

    JRadioButton addButton, subtractButton, intersectButton, exclusiveORButton, resetButton;

    public static void main(String[] a) {
        JFrame f = new JFrame();
        TArea area = new TArea();
        area.init();
        f.getContentPane().add(area);
        f.setDefaultCloseOperation(1);
        f.setSize(650, 450);
        f.setVisible(true);
    }

    public void init() {
        Container container = getContentPane();

        JPanel panel = new JPanel();
        panel.setLayout(new GridLayout(2, 2));

        resetButton = new JRadioButton("Reset", true);

        addButton = new JRadioButton("Add");
        subtractButton = new JRadioButton("Subtract");
        intersectButton = new JRadioButton("Intersect");
        exclusiveORButton = new JRadioButton("ExclusiveOR");

        ButtonGroup group = new ButtonGroup();
        group.add(resetButton);
        group.add(addButton);
        group.add(subtractButton);
        group.add(intersectButton);
        group.add(exclusiveORButton);
        group.add(resetButton);

        resetButton.addActionListener(this);
        addButton.addActionListener(this);
        subtractButton.addActionListener(this);
        intersectButton.addActionListener(this);
        exclusiveORButton.addActionListener(this);

        panel.add(addButton);
        panel.add(subtractButton);
        panel.add(intersectButton);
        panel.add(exclusiveORButton);

        container.add(panel, BorderLayout.NORTH);
        container.add(resetButton, BorderLayout.SOUTH);

        canvas = new DrawingCanvas();
        container.add(canvas);
    }

    class DrawingCanvas extends Canvas {
        GeneralPath gp;

        Ellipse2D ellipse;

        Area area1, area2;

        boolean drawFlag = true;

        boolean fillFlag = false;

        public DrawingCanvas() {
            setBackground(Color.white);
            setSize(350, 250);
            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);

            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));

            if (drawFlag) {
                g2D.draw(area1);
                g2D.draw(area2);
            }
            if (fillFlag)
                g2D.fill(area1);
        }
    }

    public void actionPerformed(ActionEvent e) {
        JRadioButton temp = (JRadioButton) e.getSource();

        if (temp.equals(addButton)) {
            canvas.area1 = new Area(canvas.gp);
            canvas.area1.add(canvas.area2);
            canvas.drawFlag = false;
            canvas.fillFlag = true;
            canvas.repaint();
        } else if (temp.equals(subtractButton)) {
            canvas.area1 = new Area(canvas.gp);
            canvas.area1.subtract(canvas.area2);
            canvas.drawFlag = false;
            canvas.fillFlag = true;
            canvas.repaint();
        } else if (temp.equals(intersectButton)) {
            canvas.area1 = new Area(canvas.gp);
            canvas.area1.intersect(canvas.area2);
            canvas.drawFlag = false;
            canvas.fillFlag = true;
            canvas.repaint();
        } else if (temp.equals(exclusiveORButton)) {
            canvas.area1 = new Area(canvas.gp);
            canvas.area1.exclusiveOr(canvas.area2);
            canvas.drawFlag = false;
            canvas.fillFlag = true;
            canvas.repaint();
        } else if (temp.equals(resetButton)) {
            if (canvas.drawFlag == false) {
                canvas.area1 = new Area(canvas.gp);
                canvas.drawFlag = true;
                canvas.fillFlag = false;
                canvas.repaint();
            }
        }
    }
}