Classpath not working

[John Eipe]

Hi,

I have created classpath for working with java as follows:

Variable: CLASSPATH
Value: .;C:\Program Files\Java\jdk1.6.0_13\bin;


is this correct? I believe once we set classpath we'll be able to work from anywhere in the computer.

I'm using Win 7.

[Vinod Tiwari]

Hi John,

Classpath should point to your JDK lib directory. It should be like C:\Program Files\Java\jdk1.6.0_13\lib .

Regards
Vinod

[Seetharaman Venkatasamy]

Vinod Tiwari wrote:
Classpath should point to your JDK lib directory. It should be like C:\Program Files\Java\jdk1.6.0_13\lib .

Wrong!. java.exe is lies under bin folder . Jhon is right.

@ john .;C:\Program Files\Java\jdk1.6.0_13\bin;

i guess you are using environment variable. what is the need of .; --> which is at the starting and ; at the end ?

[Seetharaman Venkatasamy]

John Eipe wrote: I believe once we set classpath we'll be able to work from anywhere in the computer.

Can you elaborate ?

[David Newton]

You're both wrong.

The *path* should be \bin, that's what determines what executables are available to be run without typing in their full path.

The *classpath* determines what classes and/or jar files are available without specifying them manually--and setting it to "lib" won't have any effect: jar files must be specified individually, while class hierarchy directories just need the directory name.

Setting a classpath can often cause more trouble than it's worth.

[Seetharaman Venkatasamy]

Thank you David

[John Eipe]

Thanks....

Value: .;C:\Program Files\Java\jdk1.6.0_13\bin;

I removed .; and ; from the above and still it doesn't work. When I run javac from command prompt i still get the not recognized message.

I believe once we set classpath we'll be able to work from anywhere in the computer.

I mean once it's set. we could run programs from any drive. Also isn't it a good idea to set classpaths?

[David Newton]

Are you putting quotes around the path? There are spaces in the name, so they're required.

Setting a classpath can cause more problems than it solves. Most people recommend not to. *I* set classpaths, because I run a lot of stuff from the command line, but I set it per-app, through shell scripts, depending on what I happen to be working on. In general, I don't recommend it. It's easy enough to set a different environment variable and use it in java and javac command lines.

[John Eipe]

thanks David.

I tried with quotes - nothing happens . anyways as you suggested I'll continue without setting classpaths.

[David Newton]

"Nothing" happens? I find that unlikely.

Post *exactly* what you're typing to set the path, what you type to run javac, and the output. According to your first post, you're setting the classpath to what should be the path.

[Seetharaman Venkatasamy]

David Newton wrote:Are you putting quotes around the path? There are spaces in the name, so they're required.

i think,if you are setting through environmental variable,then it is not required. it is required incase of running a java class through command promt .

[David Newton]

That is not correct; spaces are significant.

[John Eipe]

Hi David,

Below are the details:

JDK installation path: C:\Program Files\Java\jdk1.6.0_13\bin

source path: E:\JSpace\firstprograms\src
compiled classes path: E:\JSpace\firstprograms\classes

Below is what i tried on dos prompt.


E:\JSpace\firstprograms\src>javac -d E:\JSpace\firstprograms\classes -classpath "C:\Program Files\Ja
va\jdk1.6.0_13\bin" pro1.java
'javac' is not recognized as an internal or external command,
operable program or batch file.

[David Newton]

Because you're *still* not setting the path to include the directory that has the Java compiler on it.

Do you understand there is a difference between a path and a classpath?

Dave wrote:The *path* should be \bin, that's what determines what executables are available to be run without typing in their full path.

The *classpath* determines what classes and/or jar files are available without specifying them manually--and setting it to "lib" won't have any effect: jar files must be specified individually, while class hierarchy directories just need the directory name.

They are not the same thing. Here you've once again used the path as the classpath. So to reiterate: the path lists the directories that will be searched for executables. A classpath lists the the Java class directories and/or JAR files that will be used to load Java classes

The path needs to include the directory containing the Java compiler executable.

[Kuldip Shetty]

John,

Set Path variable to C:\Program Files\Java\jdk1.6.0_13\bin directory and JAVA_HOME variable to C:\Program Files\Java\jdk1.6.0_13 directory

Setting Classpath variable can be ignored for this issue.

[adam smith ii]

Agree with David, need to set the path for the o/s to find the executable such as javac. If want to do this once and forget about it until you upgrade jdk's set path via (for XP)

Control Panel => System => Advanced => Environment Variables => System variables => select variable Path and Edit

add C:\Program Files\Java\jdk1.6.0_13\bin at end of existing string. I need to copy to notepad and edit and paste back because edit window is so small.

[John Eipe]

It's working now! What exactly is JAVA_HOME for?

David,

Please correct me if i'm wrong.
Path variable is for locating exe files.
Classpath variable is for locating class files, jar, etc.
There is no way we could compile java programs without setting path variable.

Thanks.

[Campbell Ritchie]

Try a few variations. Try putting the quotes round the entire PATH. Try missing out the quotes again. Try the following at the command line:

C:\Program Files\Java\jdk1.6.0_13\bin\javac -version
and
"C:\Program Files\Java\jdk1.6.0_13\bin\javac -version"

and see whether you get the same error. Confirm that you are in fact using the 13th upgrade in its default location.