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    <p>The better solution would be providing the <code>Circle</code> with some means to determine what it should do when it moves out of bounds, however, the code is so convoluted I used this instead...</p> <p>Start by adding a <code>getBounds</code> method to your <code>Circle</code> class...</p> <pre><code>public Rectangle getBounds() { int x = centerX - radius; int y = centerY - radius; return new Rectangle(x, y, radius * 2, radius * 2); } </code></pre> <p>This will provide information about how big and where the circle is...</p> <p>Next, in your <code>MoveListener</code>, add a <code>checkBounds</code> method...</p> <pre><code>public void checkBounds(Circle circle) { int height = getHeight(); Rectangle bounds = circle.getBounds(); if (bounds.y + bounds.height &gt; height) { circle.move(0, -(height) + bounds.height); } } </code></pre> <p>This will be used to determine if a given <code>Circle</code> has moved beyond the bounds of the viewable area...</p> <p>Next, in your <code>MoveListener</code>'s <code>actionPerformed</code> method, check each circle...</p> <pre><code>c1.move(0, s); checkBounds(c1); </code></pre> <p>As so on...</p> <p><strong>Updated with quick and fast example</strong></p> <p>So, this is quick and fast example of what I've being trying to get to...</p> <p><img src="https://i.stack.imgur.com/kgQM5.gif" alt="Drop Circles"></p> <p>This uses an <code>ArrayList</code> as the primary container for the <code>Circles</code>, but it wouldn't take much to change it to use an array (in fact, some parts would become easier)....</p> <pre><code>import java.awt.BorderLayout; import java.awt.Color; import java.awt.Dimension; import java.awt.EventQueue; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.Point; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.util.ArrayList; import java.util.List; import java.util.Random; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.Timer; import javax.swing.UIManager; import javax.swing.UnsupportedLookAndFeelException; public class DropCircles { public static void main(String[] args) { new DropCircles(); } public DropCircles() { EventQueue.invokeLater(new Runnable() { @Override public void run() { try { UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) { } JFrame frame = new JFrame("Testing"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setLayout(new BorderLayout()); frame.add(new TestPane()); frame.pack(); frame.setLocationRelativeTo(null); frame.setVisible(true); } }); } public static class TestPane extends JPanel { protected static final int MAX_CIRCLES = 7; private List&lt;Circle&gt; circles; private Random rnd = new Random(); public TestPane() { circles = new ArrayList&lt;&gt;(MAX_CIRCLES); Timer timer = new Timer(40, new ActionListener() { @Override public void actionPerformed(ActionEvent e) { while (circles.size() &lt; MAX_CIRCLES) { circles.add(createCircle()); } List&lt;Circle&gt; purge = new ArrayList&lt;&gt;(MAX_CIRCLES); for (Circle circle : circles) { Point p = circle.getLocation(); p.y += circle.getYDelta(); if (p.y &gt; getHeight()) { purge.add(circle); } else { circle.setLocation(p); } } circles.removeAll(purge); repaint(); } }); timer.start(); } protected Circle createCircle() { int x = rnd.nextInt(getWidth()); int radius = 5 + rnd.nextInt(45); int speed = 1 + rnd.nextInt(8); if (x + radius &gt; getWidth()) { x = getWidth() - radius; } Circle circle = new Circle(radius, new Color(rnd.nextInt(255), rnd.nextInt(255), rnd.nextInt(255))); circle.setLocation(x, 0); circle.setYDelta(speed); return circle; } @Override public Dimension getPreferredSize() { return new Dimension(200, 200); } @Override protected void paintComponent(Graphics g) { super.paintComponent(g); Graphics2D g2d = (Graphics2D) g.create(); for (Circle circle : circles) { circle.paint(g); } g2d.dispose(); } } public static class Circle { private final int radius; private final Color color; private int x; private int y; private int yDelta; public Circle(int radius, Color color) { this.radius = radius; this.color = color; } public void setLocation(int x, int y) { this.x = x; this.y = y; } public void setLocation(Point p) { setLocation(p.x, p.y); } public Point getLocation() { return new Point(x, y); } public void setYDelta(int yDelta) { this.yDelta = yDelta; } public int getYDelta() { return yDelta; } public void paint(Graphics g) { g.setColor(color); g.fillOval(x, y, radius, radius); } } } </code></pre> <p>Basically what happens is, as a <code>Circle</code> leaves the viewable area, it is removed from the "list" and on the next tick (of the <code>Timer</code>), a new <code>Circle</code> is created to ensure that there is always seven circles on the screen (or there abouts).</p> <p>If you were to use an array. You could simply create a new <code>Circle</code> in the movement loop at the index position of the current <code>Circle</code>, effectivly replacing it...</p>
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    1. POhow can i draw a circle again if it goes too far on a JPanel
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    1. COthanks for the help but would it also work if I found the Y value of a moving circle and made a new circle appear at the top when the Y value was higher than the height of JPanel.
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    2. COThe concept is the same, but the problem you know have, is you don't which circle you are dealing with...so how to replace it in the array, but you seem to have abandoned the array, so your in double trouble...
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    3. COcant I find the Y value of the first circle I make which is called c1 so that when it goes too far I just make a new one. I tried using the array but it got a bit too complicated when I had to find the Y value of any of the random circles because I want a new random circle to appear at the top where the old circle was. So if one circle starts on the middle of the screen when it goes down to far a new circle will appear on the same x value
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