Missing .class file

Question

I run "javac" and looks that javac compile file "HelloWorldApp.java", but when I try to run "java HelloWorldApp" I have error
Exception in thread "main" java.lang.NoClassDefFoundError: HelloWorldApp/class
If I go to my directory I can no see .class file. Why?
I set varible for PATH and CLASSPATH ....

Answer 1

I see where problem is ...
I set PATH but does not work ... this is how looks
like
%SystemRoot%\system32;%SystemRoot%;%SystemRoot%\System
32\Wbem;C:\Program Files\Cisco\Call Manager Attendant
Console\jre1.4\bin;C:\Program Files\Microsoft SQL
Server\80\Tools\BINN;C:\Program
Files\Java\jdk1.6.0\bin;
After I run C:\> javac HelloWorldApp.java , javac
compile second copy of "HelloWorldApp.java" located
in C:\
On this location I found .class file ...
(I was thinking if I set PATH, I have to save application there tooNo, PATH is an environment variable that tells the operating system where to look for executable files. That tells Windows where to find the .exe files like javac and java and jar.
..or when I call "javac" <file
name>, I have to be in that directory where I saved
file)Yes.
I set CLASSPATH to "C:\Program
Files\Java\jdk1.6.0\bin" and this looks like works
fine.No, this is a waste. In spite of what that tutorial tells you, there's no need for a CLASSPATH environment variable. (Yours is wrong, BTW.) CLASSPATH is for the JVM. It tells the compiler and runtime where to look for .class files that it needs.
The right way to set CLASSPATH is using the -classpath option on javac.exe and java.exe. Read those docs.
After I run "java HelloWorldApp" I have error because
CLASSPATH is set for diferent location ...java.exe ignores your CLASSPATH anyway.
>
When I moved my .class file from loaction "C:\" to
"C:\Program Files\Java\jdk1.6.0\bin " and run
"C:\>java HelloWorldApp", I did not have any error
and application works fine.That's wrong. Your code does not belong in there. Ever.
>
So, why my PATH does not work for "javac" ???Your PATH works fine, because Windows found javac.exe and java.exe. It's CLASSPATH that's incorrect.
Compile like this:
javac *.javaRun like this:
java -classpath . HelloWorldAppNote the "dot" after -classpath. That sets the CLASSPATH to the current directory.
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