— Scott McNealy, Sun Microsystems Chairman, President and ceo

private Antenna ant;
No actual Antenna object is made on the heap unless 
or until the reference variable is assigned a new 
Antenna object.
private Antenna ant = new Antenna();
int
long
Object with two primitive instance variables. 
Space for the variables lives in the object.
Object with one non-primitive instance variable—
a reference to an Antenna object, but no actual 
Antenna object This is what you get if you 
declare the variable but don’t initialize it with 
an actual Antenna object.
Antenna
ant
public class CellPhone {
private Antenna ant;
}
public class CellPhone {
private Antenna ant = new Antenna();
}
Object with one non-primitive instance variable, 
and the Antenna variable is assigned a new 
Antenna object.
x
y
Antenna
ant
CellPhone object
CellPhone object
Antenna object
CellPhone object

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240
 
chapter 9
object 
creation
The miracle of object creation
Now that you know where variables and objects live, we can dive into 
the mysterious world of object creation. Remember the three steps 
of object declaration and assignment: declare a reference variable, 
create an object, and assign the object to the reference.
But until now, step two—where a miracle occurs and the new object 
is “born”—has remained a Big Mystery. Prepare to learn the facts of 
object life. Hope you’re not squeamish.
1
Declare a reference 
variable
Duck reference
myDuck
Duck myDuck =
 new Duck();
Create an object
Review the 3 steps of object 
declaration, creation and assignment:
Duck object