Java Reference
In-Depth Information
EXAMPLE
Suppose that
HourlyEmployee
is a derived class of
Employee
and that
employeeObject
and
hourlyEmployeeObject
are created as follows:
Employee employeeObject =
new
Employee();
HourlyEmployee hourlyEmployeeObject =
new
HourlyEmployee();
Then,
employeeObject.getClass() == hourlyEmployeeObject.getClass()
returns
false
.
employeeObject
instanceof
Employee
returns
true
.
hourlyEmployeeObject
instanceof
Employee
returns
true
.
employeeObject
instanceof
HourlyEmployee
returns
false
.
hourlyEmployeeObject
instanceof
HourlyEmployee
returns
true
.
Self-Test Exercises
18.
Redefi ne the method
equals
given in Display 7.10 using
instanceof
instead
of
getClass()
. Give the complete defi nition. Remember, we do not want you
to defi ne
equal
s this way in your class defi nitions; this is just an exercise.
19.
Redefi ne the
equals
method of the class
HourlyEmployee
( Display 7.3 ) so
that it has a parameter of type
Object
and follows the other guidelines we gave
for an
equals
method. Assume the defi nition of the method
equals
for the
class
Employee
has been changed to be as in Display 7.10. (Remember, you
should use
getClass()
, not
instanceof.)
