A direct subclass of javacard.framework.Applet must implement the abstract
process-method.

An applet is implemented by subclassing the abstract Applet class from
the JavaCard API. The Applet class has only one constructor that takes
no arguments. The constructor of the subclass is usually only called by
the static install-method, which must be implemented. The constructor
is usually private. The process-method of Applet is abstract and must
be implemented in a direct, non-abstract subclass. How it should be
implemented depends entirely on the purpose of the applet. Typically,
the buffer of the incoming APDU object is read and examined. Depending
on its content it may be altered, and further methods may be called on
the APDU object.

A subclass of javacard.framework.Applet must implement the abstract
install-method.

The constructor of an applet must be public.

An applet must implement a static install method with the following
signature:
public static void install(byte[] bArray, short bOffset, byte bLength)

An applet is implemented by subclassing the abstract Applet class from
the JavaCard API.

The constructor of an applet which is a direct subclass of
javacard.framework.Applet must call the superclass constructor that
takes a byte[]: super(myByteArray);