what does this error message mean?

[eric lee]

when i run javac Hello.java,it compile ok,no error message but when i run java Hello,it shows
Exception in thread "main"
java.lang.NoClassDefFoundError:Hello
what wrong?
my code below:
------------------------------------------------
class Hello {
public static void main (String[] in) {
System.out.print("Hello World!");
}
}

[Neil Laurance]

What is your CLASSPATH environment variable?
If this variable is unset, java will look in the current directory for your class file. If the CLASSPATH is set, you must ensure that the current directory is included in the CLASSPATH.
The simplest way is:
java -cp . Hello

[eric lee]

Hi Neil:
how to set up my class path? Thanks

[Cindy Glass]

That depends on what OS that you are running.

[eric lee]

my OS is Win2000, so how can i set up java CLASSPATH environment ? how to add it ?

[Dirk Schreckmann]

Try a quick search on this forum. This topic has been talked about a lot. The search page link is at the top right of this page.
Any luck yet?

[eric lee]

ok, i figure out, thanks everyone