Class Libraries in Java

println( ) and print( ). As mentioned, these methods are members of the System class,
which is a class predefined by Java that is automatically included in your programs. In the
larger view, the Java environment relies on several built-in class libraries that contain many
built-in methods that provide support for such things as I/O, string handling, networking,
and graphics. The standard classes also provide support for windowed output. Thus, Java
as a totality is a combination of the Java language itself, plus its standard classes. As you
will see, the class libraries provide much of the functionality that comes with Java. Indeed,
part of becoming a Java programmer is learning to use the standard Java classes.