Mängder av körfel i Java

Exception in thread "AWT-EventQueue-0" java.lang.ClassCastException
        at javax.swing.LayoutComparator.compare(Unknown Source)
        at javax.swing.LayoutComparator.compare(Unknown Source)
        at java.util.TimSort.binarySort(Unknown Source)
        at java.util.TimSort.sort(Unknown Source)
        at java.util.TimSort.sort(Unknown Source)
        at java.util.Arrays.sort(Unknown Source)
        at java.util.Collections.sort(Unknown Source)
        at javax.swing.SortingFocusTraversalPolicy.enumerateAndSortCycle(Unknown Source)
        at javax.swing.SortingFocusTraversalPolicy.getFocusTraversalCycle(Unknown Source)
        at javax.swing.SortingFocusTraversalPolicy.getFirstComponent(Unknown Source)
        at javax.swing.LayoutFocusTraversalPolicy.getFirstComponent(Unknown Source)
        at javax.swing.SortingFocusTraversalPolicy.getDefaultComponent(Unknown Source)
        at java.awt.FocusTraversalPolicy.getInitialComponent(Unknown Source)
        at java.awt.DefaultKeyboardFocusManager.dispatchEvent(Unknown Source)
        at java.awt.Component.dispatchEventImpl(Unknown Source)
        at java.awt.Container.dispatchEventImpl(Unknown Source)
        at java.awt.Window.dispatchEventImpl(Unknown Source)
        at java.awt.Component.dispatchEvent(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.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
        at java.awt.EventQueue$4.run(Unknown Source)
        at java.awt.EventQueue$4.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.SequencedEvent.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.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
        at java.awt.EventQueue$4.run(Unknown Source)
        at java.awt.EventQueue$4.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)

import se.lth.cs.pt.dots.events.DotWindow;
import se.lth.cs.pt.dots.Color;
import se.lth.cs.pt.dots.events.GameEvent;
import se.lth.cs.pt.io.Keyboard;
import java.util.*;


class Snake {
    
    public static void main(String[] args) {
        new Snake().run();
    }
    
    DotWindow w;
    Runner runner;
    List<int[]> tail = new LinkedList<int[]>();
    int tailLength;
    
    
    void run() {
	setup();
	
	int tickCount = 0;
	dance: while (true) {
	    GameEvent event = w.getNextEvent();
	    switch (event.getKind()) {
	    case GameEvent.TICK:
		tickCount++;
		if(tickCount%10==0) {
		    tailLength++;
		}
		System.out.println("TICK");
		manageTail(runner.getPos());
		runner.forward();
		if (youHitSomething()) {
		    paintRed(runner.getPos());
		    break dance;
		}
		paintRed(runner.getPos());
		break;
	    case GameEvent.KEY_PRESSED:
		switch (event.getKey()) {
		case 'a':
		    System.out.println("VÄNSTER");
		    runner.turnLeft();
		    break;
		case 'd':
		    System.out.println("HÖGER");
		    runner.turnRight();
		    break;
		}
	    }
	    
	}
    }
    
    void manageTail(int[] input) {
	tail.addFirst(input);
	paintBlue(tail.get(0));
	paintWhite(tail.getLast());
	tail.removeLast();
    }

    void paintTail() {
	for (int[] coordinate : tail) {
	    paintBlue(coordinate);
	}
	//paintWhite(tail.get(tailLength-1));
    }
    

    boolean youHitSomething() {
	if (!w.getDot(runner.getPos()[0], runner.getPos()[1]).equals(Color.WHITE)) {
	    return true;
	}
	return false;
    }

    void paintRed(int[] input) {
	w.setDot(input[0], input[1], Color.RED);
    }

    void paintBlue(int[] input) {
	w.setDot(input[0], input[1], Color.BLUE);
    }

    void paintWhite(int[] input) {
	w.setDot(input[0], input[1], Color.WHITE);
    }
    
    void setup() {
	int size = Keyboard.nextInt("Ange storlek! ");
	int speed = 100;
	w = new DotWindow(size, size, 10);
	w.setAutoUpdate(false);
	for (int k = 0; k<size; k++) {
	    w.setDot(k, 0, Color.BLACK);
	    w.setDot(k, size-1, Color.BLACK);
	    w.setDot(0, k, Color.BLACK);
	    w.setDot(size-1, k, Color.BLACK);
	}
	runner = new Runner(size);
	w.setDot(runner.getX(), runner.getY(), Color.RED);
	w.timeStep(speed);
	w.checkKeys(true, false, false);
	w.update();
	w.setAutoUpdate(true);
    }
}

    
class Runner {
    private int xPos;
    private int yPos;
    private int direction;
    private int[] coordinates = new int[2];

    public Runner (int size) {
	xPos = size/2;
	yPos = size/2;
	direction = 1;
	updateCoordinates();   
    }
    
    public int getX () {
	return xPos;
    }
    
    public int getY () {
	return yPos;
    }

    public int[] getPos() {
	return coordinates;
    }
    
    public void turnRight () {
	if (direction==1) {
	    direction=4;
	} else {
	    direction--;
	}		
    }
    
    public void turnLeft () {
	if (direction==4) {
	    direction=1;
	} else {
	    direction++;
	}
    }

    public void forward () {
	switch (direction) {
	case 1:
	    xPos++;
	    break;
	case 2:
	    yPos--;
	    break;
	case 3:
	    xPos--;
	    break;
	case 4:
	    yPos++;
	    break;
	}
	updateCoordinates();
    }

    private void updateCoordinates() {
	coordinates[0] = xPos;
	coordinates[1] = yPos;
    }
}