Hello folks, I recently started learning Java and bought a book to look at some examples. When I copied this example program out of the book I get a null pointer exception. Most of the other programs worked perfectly this is the only one iv had a problem with so far. At first i thought it was because I didn't have an image called bug1.gif in the same folder as my java files however that was not the case.

The error I get is
Exception in thread "main" java.lang.NullPointerException
at javax.swing.ImageIcon.(init)(ImageIcon.java:167)
at LabelFrame.(init)(LabelFrame.java:23)
at LabelTest.main(LabelTest.java:7)

import java.awt.FlowLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.SwingConstants;
import javax.swing.Icon;
import javax.swing.ImageIcon;

public class LabelFrame extends JFrame
{
	private JLabel label1;
	private JLabel label2; // ImageIcon
	private JLabel label3;

	public LabelFrame()
	{
		super("Testing JLabel");
		setLayout(new FlowLayout());

		label1 = new JLabel("Label with Text");
		label1.setToolTipText("This is label1");
		add(label1);

		Icon bug = new ImageIcon(getClass().getResource("bug.gif"));
		label2 = new JLabel("Label with text and icon",bug,SwingConstants.LEFT);
		label2.setToolTipText("This is label2");
		add(label2);

		label3 = new JLabel();
		label3.setText("Label with icon and text at bottom");
		label3.setIcon(bug);
		label3.setHorizontalTextPosition(SwingConstants.CENTER);
		label3.setVerticalTextPosition(SwingConstants.BOTTOM);
		label3.setToolTipText("This is label3");
		add(label3);
	}
}
import javax.swing.JFrame;

public class LabelTest
{
	public static void main(String args[])
	{
		LabelFrame labelFrame = new LabelFrame();
		labelFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		labelFrame.setSize(275,180);
		labelFrame.setVisible(true);
	}
}

Hi.
At first glance it seem that the error is caused by this instruction:

ImageIcon(getClass().getResource("bug.gif"));

Can you please tell where you put the "bug.gif" file?

I have all the files stored together in the same folder (LabelTest, LabelFrame, bug1.gif)

If it is so it should work; please check spelling.

The gif file is named "bug.gif" or "bug1.gif"?

If it is so it should work; please check spelling.

The gif file is named "bug.gif" or "bug1.gif"?

ah that was it, changed it to bug.gif and it works, thank you so much for the help

This article has been dead for over six months. Start a new discussion instead.