You can either add it to your commandline, or you can go to the Control
Panel -> System -> Advanced -> Environment Variables and add it permenatly.

You can use "set classpath="...or use a batch file to override your java
command to send the classpath:

java -cp "c:\my\classpath\" DriveThrough

Remember also that java  will not load your class file if the package is set
to something...you'll need to call it as "My.DriveThrough" or similar. That
is a common mistake I often make when running on command line.

Send me the class that does it and let me figure it
out

Just Right click on MyComputer After clicking u will see a Frame in frame there
is a option Advanced just click on it.

in Advanced there is a button named Environment Variables just Click on this .

After clicking u will see another Frame will Appe...

then Go to System variables then select Path afther this click on edit button.

the another Box Will appe...... in the secont field if something in this field
then put ;

this and after it put your java  Path ok.

then just simple click on ok ok ok.