Exception in thread "main" java.lang.NullPointerException

The full problem:

Exception in thread "main" java.lang.NullPointerException
at javax.swing.ImageIcon.<init>(ImageIcon.java:181)
at rtype.Craft.<init>(Craft.java:19)
at rtype.Board.<init>(Board.java:27)
at rtype.RType.<init>(RType.java:9)
at rtype.RType.main(RType.java:20)

My Code:

Code :

Craft.Java
package rtype;
 
import java.awt.Image;
import java.awt.event.KeyEvent;
 
import javax.swing.ImageIcon;
 
public class Craft {
 
	private String craft = "/users/gregorystedman/images/craft.png";
 
	private int dx;
	private int dy;
	private int x;
	private int y;
	private Image image;
 
	public Craft() {
		ImageIcon ii = new ImageIcon(this.getClass().getResource(craft));
		image = ii.getImage();
		x = 40;
		y = 60;
	}
 
	public void move() {
		x += dx;
		y += dy;
	}
 
	public int getX() {
		return x;
	}
 
	public int getY() {
		return y;
	}
 
	public Image getImage() {
		return image;
	}
 
	public void keyPressed(KeyEvent e) {
 
		int key = e.getKeyCode();
 
		if (key == KeyEvent.VK_LEFT) {
			dx = -1;
		}
 
		if (key == KeyEvent.VK_RIGHT) {
			dx = 1;
		}
 
		if (key == KeyEvent.VK_UP) {
			dy = -1;
		}
 
		if (key == KeyEvent.VK_DOWN) {
			dy = 1;
		}
	}
 
	public void keyReleased(KeyEvent e) {
		int key = e.getKeyCode();
 
		if (key == KeyEvent.VK_LEFT) {
			dx = 0;
		}
 
		if (key == KeyEvent.VK_RIGHT) {
			dx = 0;
		}
 
		if (key == KeyEvent.VK_UP) {
			dy = 0;
		}
 
		if (key == KeyEvent.VK_DOWN) {
			dy = 0;
		}
	}
}

Code :

Board.java
 
package rtype;
 
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
 
import javax.swing.JPanel;
import javax.swing.Timer;
 
public class Board extends JPanel implements ActionListener {
 
	private Timer timer;
	private Craft craft;
 
	public Board() {
 
		addKeyListener(new TAdapter());
		setFocusable(true);
		setBackground(Color.BLACK);
		setDoubleBuffered(true);
 
		craft = new Craft();
 
		timer = new Timer(5, this);
		timer.start();
	}
 
	public void paint(Graphics g) {
		super.paint(g);
 
		Graphics2D g2d = (Graphics2D)g;
		g2d.drawImage(craft.getImage(), craft.getX(), craft.getY(), this);
 
		Toolkit.getDefaultToolkit().sync();
		g.dispose();
	}
 
	public void actionPerformed(ActionEvent e) {
		craft.move();
		repaint();
	}
 
	private class TAdapter extends KeyAdapter {
		public void keyReleased(KeyEvent e) {
			craft.keyReleased(e);
		}
 
		public void keyPressed(KeyEvent e) {
			craft.keyPressed(e);
		}
	}
}

Code :

RType.java
 
package rtype;
 
import javax.swing.JFrame;
 
public class RType extends JFrame {
 
	public RType() {
 
		add(new Board());
 
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setSize(400, 300);
		setLocationRelativeTo(null);
		setTitle("R - Type");
		setResizable(false);
		setVisible(true);
	}
 
	public static void main(String[] args) {
		new RType();
	}
}