Classpath probelm--duke dollars available

Question

Basically I have the following problem
I have downloaded the comm api. I have installed it and set up the classpaths.
set CLASSPATH=c:\j2sdk1.4.1_01\lib\comm.jar (This points to the api)
set CLASSPATH=c:\commapi\samples\Blackbox\BlackBox.jar;%CLASSPATH%
(This is one of the examples with it)
And when I run it it is fine.
I have also made my own simple program called ListPorts.When I compile it is fine but when I try to run it I get errors.
java c:\ListPorts
Can anyone help me please

Answer 1

If you are placing it on the root of C:\, then you should add "C:\" to your classpath.
As jesper1 stated don't prepend the directory name to the classname. You NEVER do this... NEVER, NEVER, NEVER. The argument is a fully qualified classname. What I mean by fully qualified is the full package & classname.
For example:
if you were trying to run a class "i.am.a.java.Newbie"
o the "i.am.a.java" part is the package
o and the "Newbie" piece is the classname.
A fully qualified classname combines both the package and classname.
Note the syntax defined below. Notice on the first "Usage" line how it says "class". It doesn't say "path to class/class" or anything like that. It just says class.
C:\>java
Usage: java [-options] class [args...]
           (to execute a class)
   or  java -jar [-options] jarfile [args...]
           (to execute a jar file)
where options include:
    -client       to select the "client" VM
    -server       to select the "server" VM
    -hotspot      is a synonym for the "client" VM  [deprecated]
                  The default VM is client.
    -cp -classpath <directories and zip/jar files separated by ;>
                  set search path for application classes and resources
    -D<name>=<value>
                  set a system property
    -verbose[:class|gc|jni]
                  enable verbose output
    -version      print product version and exit
    -showversion  print product version and continue
    -? -help      print this help message
    -X            print help on non-standard options
    -ea[:<packagename>...|:<classname>]
    -enableassertions[:<packagename>...|:<classname>]
                  enable assertions
    -da[:<packagename>...|:<classname>]
    -disableassertions[:<packagename>...|:<classname>]
                  disable assertions
    -esa | -enablesystemassertions
                  enable system assertions
    -dsa | -disablesystemassertions
                  disable system assertions