omo_to_dun:

Wrong! In windows, there are two types of environment variables namely: user variables and system variables. Setting a variable, say PATH, as a user variable will restrict it to the account of the person setting it while setting the variable as system variable(you have to have administrative privileges to do this) will make it available for all the accounts in the system. You set the CLASSPATH when you want the location of your class packages to be known to the JVM. For example, if I have some classes, say Driver.class, Mechanic.class, Person.class, and Test.class in a package edu.caltech which is in turn located in the folder C:\omo_to_dun\nairaland\2011,

I can then add C:\omo_to_dun\nairaland\2011\ to my CLASSPATH so that I can import them like so:

import edu.caltech.*;

If I do not add C:\omo_to_dun\nairaland\2011\ [/b]to my [b]CLASSPATH, then the above import will fail, unless I am currently in the directory C:\omo_to_dun\nairaland\2011.

So, stop laughing in Swahili and pick up a good Java Book!

Otuabaroku:

And I asked the guy to copy the java bin directory to  his CLASSPATH that is located at the system variable( by doing so, all users of the system would have access to it). Please, tell me how is this different to what I said before or what you just stated. @omo_to_dun  na you know

Otuabaroku:

Windows has two environmental variables, user and system variables. CLASSPATH is located at the System  variables while the PATH is located at the user variables.

Luka316:

@all infact iam learning from your argument, but pls is enough, let it not lead to something else[when two elephant fight is the grass(me) that suffers]

@omo_to_dun pls how can i get the[b] examples of code found in [/b] "Java how to program 6e" i try downloading it from their (deitel) website but i could'nt pls if u can i would e greatful.
thx

omo_to_dun:

Because setting CLASSPATH only affects the classes you want to import---it does not add the directory where java, javac, appletviewer and all the other programs you need to compile and run java programs are located, which is what the OP wanted. If he had added C:\Sun\SDK\java\bin to CLASSPATH, but not to PATH, typing java at the command line wouldn't work. I understand what you are saying, but if he wants to set his Java Development Environment for all users he has to set PATH as a system variable. PATH is not exclusive to user variables, you can also create a new variable in system called PATH and add your directories to it.
Your understanding is severely limited! Not every account on Windows has a user variable called PATH. My PATH variable exists as a system variable(Windows 7). Of course, I can create a PATH user variable if I wanted to, in which case the setting would affect only my account. Who says CLASSPATH is located at the system variables? You really need to read more! CLASSPATH system variable is created either by you or some other user with administrative privileges(it does not come with Windows) and you can make it a user or system variable, depending on how you want it to affect other accounts. And really, unless you are developing a large scale application, no one sets the CLASSPATH. The OP is a newbie, he does not need to set CLASSPATH until he starts modularizing his classes and placing them in packages. Like I said, CLASSPATH is not exclusive to system variables, you can have PATH as both user and system variables. You can also have CLASSPATH as both user and system variable. Matter of fact, you can have any legal string as both user and system variables. For example, if I have CLASSPATH in system variables, then this CLASSPATH will be set for everyone on the system, as you correctly pointed out. However, if I want the CLASSPATH to affect only me, then I'll create a variable called CLASSPATH as user variable to that effect. Try it: set only your CLASSPATH an see if you can compile anything. (Of course, you'd have to unset the PATH variable).

Official tutorial on CLASSPATH and PATH variables
http://download.oracle.com/javase/tutorial/essential/environment/paths.html

Once again CLASSPATH sets directories for class packages, while PATH sets directories for location of development binaries.