Swing Game EyeHandCoordination

Question copied from the book:


(Game: eye-hand coordination) Write a program that displays a circle
of radius 10 pixels filled with a random color at a random location on
a panel, as shown in Figure 16.28c. When you click the circle, it
disappears and a new randomcolor circle is displayed at another random
location. After twenty circles are clicked, display the time spent in
the panel, as shown in Figure 16.28d.

My solution:

```
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class EyeHandCoordination extends JFrame {
private final int CIRCLE_RADIUS = 10;
private final int TOTAL_CIRCLES = 20;
private RandomCirclePanel panel = new RandomCirclePanel();

public EyeHandCoordination() {
add(panel);
}

public static void main(String[] args) {
EyeHandCoordination frame = new EyeHandCoordination();
frame.setTitle("EyeHandCoordination");
frame.setSize(300, 300);
frame.setLocationRelativeTo(null); // Center the frame
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}

private class RandomCirclePanel extends JPanel {
private long startTime;
private long endTime;

private int circleX = 0;
private int circleY = 0;

private int currentCircle = 0;

public RandomCirclePanel() {
startTime = System.currentTimeMillis();

addMouseListener(new MouseAdapter() {
@Override
public void mousePressed(MouseEvent e) {
// Check if in circle
if (inCircle(e.getX(), e.getY()) && currentCircle = TOTAL_CIRCLES) {
g.setColor(Color.BLACK);
endTime = System.currentTimeMillis();
FontMetrics fm = g.getFontMetrics();
String s = "Time spent: " + ((endTime - startTime) / 1000.0) + " seconds";
g.drawString(s, width / 2 - fm.stringW

public boolean inCircle(int mouseX, int mouseY) {
    if (distanceFromCenterOfCircle(mouseX, mouseY) <= CIRCLE_RADIUS) {
        return true;
    }

    return false;
}

Can be

public boolean inCircle(int mouseX, int mouseY) {
    return distanceFromCenterOfCircle(mouseX, mouseY) <= CIRCLE_RADIUS;
}

(int)(Math.random() (getWidth() - CIRCLE_RADIUS 2));

g.setColor(new Color((int)(Math.random() 256), (int)(Math.random() 256), (int)(Math.random() * 256)));

Looks like you could benefit from a function that takes an integer as maximum value... and then returns an integer between 0 and max minus 1.

Which does exist - you'd simply create a new instance of Random and then call randomInstance.nextInt(maxValue).

Lastly, I think you would be better off by renaming the currentCircle variable to amountOfCirclesDisplayed because that's what it really is. currentCircle seems to point to the idea that somewhere, you have a list of circles, and right now, you're working on 1 specific circle. But that's not true, because you HAVE no list of circles and all that really matters is how many you've displayed so far.

StackExchange Code Review Q#139181, answer score: 2