ImageIcon调试测试的NullPointerException

Question

运行此程序时，我会收到此错误代码：

   java.lang.NullPointerException
    at javax.swing.ImageIcon.<init>(ImageIcon.java:217)
    at DebugMe.<init>(DebugMe.java:16)
    at DebugMe.main(DebugMe.java:31)

但是编译器本身没有抛出任何错误。 ＆＃34; debug.jpeg＆＃34; image也在程序运行的同一文件夹中。

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

public class DebugMe extends JFrame
{
    private String message = "Congratulations, the program is working again.";
    Image debug = new ImageIcon(this.getClass().getResource("debug.jpeg")).getImage();
    int x; //Initialized x

    /**
     * Constructor for objects of class DebugMe
     */
    public DebugMe()
    {
        x = 0;
        setSize(500, 500);
        setVisible(true); //Lowercase t on true
    }

    public static void main(String[] args)
    {
        DebugMe myDebugMe = new DebugMe(); //capitalized me in Debugme
        int x;
    }

    public void paint(Graphics g)
    {
        super.paint(g);
        g.drawString("message", 100, 100);
        g.drawImage(debug, 100, 200, Color.BLUE, this);
    }
}