Problem scenario
You have compiled the source code of a Java program into bytecode (with a .class extension). You try to run it (execute the bytecode) with a javac command (javac HelloWorld), but you get "error: Class names, 'HelloWorld', are only accepted if annotation processing is explicitly requested
1 error "
What should you do?
Solution
Run it with the java command like this (with no ".class" extension): java HelloWorld