Learn the four types of polymorphism in Java, then start using subtype polymorphism ... System.out.println(subclass instanceof Superclass); // Output: true System.out.println(superclass instanceof ...

Java programs without a graphical user interface use a computer's command line to interact with the user. It is vital that the program's command line output is properly formatted and spaced so ...

In prior Java 101 articles, I referred to the concepts of redirection, standard input device, and standard output device. To demonstrate inputting data, several examples called System.in.read().