Here is my main code:
package main;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Panel extends JPanel{
public Thread update;
public YourPaddle pa;
public EnemyPaddle ea;
public static int fps;
public static long lasttimechecked = System.nanoTime();
public static int frames = 0;
public Panel(){
addKeyListener(new TAdapter());
setFocusable(true);
setBackground(Color.BLACK);
setDoubleBuffered(true);
pa = new YourPaddle();
update = new Thread(){
public void run(){
for (int i = 0; i < 2; ) {
pa.gor();
try{
ea.gorg();
}catch(Exception e){
}
repaint();
try {
Thread.sleep(2);
}catch(Exception e){
}
frames++;
if (System.nanoTime() - lasttimechecked >= 1000000000){
fps = frames;
frames = 0;
lasttimechecked = System.nanoTime();
}
}
}
};
update.start();
}
public void paint(Graphics g){
super.paint(g);
g.setColor(Color.white);
g.drawLine(300, 10, 300, 340);
g.drawImage(pa.i, 20, pa.getY(), this);
g.drawImage(ea.i, 550, ea.getYy(), this);
g.drawString("FPS: " + fps + " Y: " + pa.getY(), 10,17);
Toolkit.getDefaultToolkit().sync();
g.dispose();
}
private class TAdapter extends KeyAdapter {
public void keyReleased(KeyEvent e) {
pa.keyReleased(e);
ea.keyReleased(e);
}
public void keyPressed(KeyEvent e) {
pa.keyPressed(e);
ea.keyReleased(e);
}
}
}
Here s the thing basically, the4 game is pong and there is one paddle named pa in this class. The pa paddle works, but i copied the same thing into another class but renamed all of the methods. When i run the program, pa paddle works but the enemypaddle(ea) gives me an error Saying the method is a null pointer exception. Here s the stack trace:
Exception in thread "Thread-2" java.lang.NullPointerException
at main.Panel$1.run(Panel.java:31)
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at main.Panel.paint(Panel.java:61)
at javax.swing.JComponent.paintChildren(Unknown Source)
at javax.swing.JComponent.paint(Unknown Source)
at javax.swing.JComponent.paintChildren(Unknown Source)
at javax.swing.JComponent.paint(Unknown Source)
at javax.swing.JLayeredPane.paint(Unknown Source)
at javax.swing.JComponent.paintChildren(Unknown Source)
at javax.swing.JComponent.paintToOffscreen(Unknown Source)
at javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(Unknown Source)
at javax.swing.RepaintManager$PaintManager.paint(Unknown Source)
at javax.swing.RepaintManager.paint(Unknown Source)
at javax.swing.JComponent.paint(Unknown Source)
at java.awt.GraphicsCallback$PaintCallback.run(Unknown Source)
at sun.awt.SunGraphicsCallback.runOneComponent(Unknown Source)
at sun.awt.SunGraphicsCallback.runComponents(Unknown Source)
at java.awt.Container.paint(Unknown Source)
at java.awt.Window.paint(Unknown Source)
at javax.swing.RepaintManager$3.run(Unknown Source)
at javax.swing.RepaintManager$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at javax.swing.RepaintManager.paintDirtyRegions(Unknown Source)
at javax.swing.RepaintManager.paintDirtyRegions(Unknown Source)
at javax.swing.RepaintManager.prePaintDirtyRegions(Unknown Source)
at javax.swing.RepaintManager.access$1000(Unknown Source)
at javax.swing.RepaintManager$ProcessingRunnable.run(Unknown Source)
at java.awt.event.InvocationEvent.dispatch(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$200(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
Can anyone say why only one paddle wont work? it s the same thing...
