NoClassDefFoundError

[Jon Camilleri]

Any idea why the code here is returning an error, when trying to compile it from the command line?

Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.
...

>javac GridBagLayout.java
javac: file not found: GridBagLayout.java
Usage: javac <options> <source files>
use -help for a list of possible options

>javac GridBagLayoutDemo.java

>java GridBagLayoutDemo.java
Exception in thread "main" java.lang.NoClassDefFoundError: GridBagLayoutDemo/java
Caused by: java.lang.ClassNotFoundException: GridBagLayoutDemo.java
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
Could not find the main class: GridBagLayoutDemo.java. Program will exit.

Basically, I was trying to understand whether changing the GridBagConstraints would have a visual impact on the display:

...
pane.add(button, c);

	button = new JButton("5");
	c.fill = GridBagConstraints.HORIZONTAL;  ... change to GridBagConstraints.NORTHEAST; ?
...

[Steve Fahlbusch]

Well the first thing would be that your java command is referencing your source file.

[Wim Vanni]

package layout;

/*
 * GridBagLayoutDemo.java requires no other files.
 */

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

public class GridBagLayoutDemo {
//...

The fact that the class is part a of a package 'layout' translates into a folder structure that you don't seem to follow.
...
Just noticed Steve is responding in the same way. That probably means I'm not awfully wrong in my answer

Cheers
Wim