PPT Slide

class Human {

String strName;

static int iPopulation = 0;

public Human (String strName) {

this.strName = strName;

iPopulation++;

} // of constructor

} // of Human

Instance vs. Class Variables

one change

As we know, this declares a strName String for each instance.

Thus, each Human will have its own name.

NOTE:

Each Human does not get an iPopulation counter.

This declares a single iPopulation counter for the class Human itself. It is a class variable.

Thus, each Human will increment this single shared counter by 1.