PPT Slide

// Assume we have vector v and int k.

// Assume int k is an index within the// range [0..(v.size( ) - 1)].

Object o;

o = v.elementAt(k); // no cast needed, already Object

if (o instanceof Student)

{

// do stuff for Student

}

if (o instanceof Cafeteria)

{

// do stuff for Cafeteria

}

Vectors

Vectors and instanceof:

Design issue:

This example is legal Java, but is it good programming?