Getting error “cannot find or load main class HelloWorld”

Question

I have this simple code:

public class HelloWorld{
    public static void main(String[] args){
        System.out.println(\"HelloWorld\");
    }
}

Answer 1

You could get this behaviour if you have an incorrect / inappropriate setting of the CLASSPATH environment variable; e.g. the current directory isn't on the classpath. (It is by default ... )

Try this:

java -classpath . HelloWorld

Assuming that works ... the problem is your understanding of the concept of the "classpath". This is explained well by the Oracle documentation:

• The java & javac command documentation ... particular the -classpath argument
• Setting the Classpath.
• The Java Tutorial - PATH and CLASSPATH