Compare inheritance and composition, the two fundamental ways to relate Java classes, then practice debugging ClassCastExceptions in Java inheritance.

For example, a Java program obtains file I/O (input/output) services by creating objects from various file-related classes in Java’s class library and calling their methods.

Spacing of Output in Java. 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 ...