In case, Java is not recognized, there is a high chance that the Java installed on your computer is corrupted. So, we need to uninstall Java and then install a fresh copy of the same by following ...

Java has the Boolean type, so you actually have the keywords 'true' and 'false' in your code. C, for example, doesn't so it doesn't evaluate to 0. C doesn't have the Boolean type, it's just an int.