Unable to run HelloWorld from command line

Question

OK, I just cannot get java to run my .class files: I follow steps in Oracle tutorial and try to run this program:

class HelloWorldApp {
    public static void main(String[] args) {
        System.out.println("Hello World!"); // Display the string.
    }
}

Compiling OK:

PS C:\Users\Ztaz> javac .\HelloWorldApp.java

But after I try to run it, I get this:

PS C:\Users\Ztaz> java .\HelloWorldApp.class
Error: Could not find or load main class .\HelloWorldApp.class

no exception, nothing.

Here's my PATH variable, if it helps (split into lines, for readability):

%JBOSS_HOME%;
%SYSTEMROOT%;
%M2%;
%JAVA_HOME%\bin;
...

JAVA_HOME is set to "C:\Program Files\Java\jdk1.7.0". My question sounds a lot like this one but I had this problem on Java SE 6 as well, so I decided to post separate question.

Answer 1

Run it without the .class: java HelloWorldApp

This causes issues for lots of people starting out with Java. Not sure why Java doesn't just look for both files (the name provided and the name with .class appended).