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Answer 4

C. 9 17.64

Explanation 4

When the square method is called on an object of the Subclass type passing an int as a parameter, there is an exact match to the required parameter type of the square method defined in that class. Thus, the method is properly selected and executed.

When the square method is called on an object of the Subclass type passing a double as a parameter, the version of the square method defined in the Subclass type is not selected. The double value is not assignment compatible with the required type of the parameter (an int is narrower than a double ).

Having made that determination, the system continues searching for an overloaded method with a required parameter that is either type double or assignment compatible with double . It finds the version inherited from Superclass that requires a double parameter and calls it.

The bottom line is, overloaded methods can occur up and down the inheritance hierarchy.

Back to Question 4

Answer 3

A. Compiler Error

Explanation 3

Return type is not a differentiating feature

This is not a subtle issue. This program illustrates the important fact that the return type does not differentiate between overloaded methods having thesame name and formal argument list.

For a method to be overloaded, two or more versions of the method must have the same name and different formal arguments lists.

The return type can be the same, or it can be different (it can even be void) . It doesn't matter.

These two methods are not a valid overload

This program attempts to define two methods named square , each of which requires a single incoming parameter of type double . One of the methods casts its return value to type int and returns type int . The other method returns type double .

The JDK 1.3 compiler produced the following error:

Ap081.java:28: square(double) is already defined in Workerpublic double square(double y){

Back to Question 3

Answer 2

C. float 9.0 double 17.64

Explanation 2

This program is a little more subtle

Once again, the program defines two overloaded methods named square . However, in this case, one of the methods requires a single incoming parameterof type float and the other requires a single incoming parameter of type double . (Suffice it to say that the float type is similar to the double type, but with less precision. It is a floating type, not an integer type. The double type is a 64-bit floating type and the float type is a 32-bit floating type.)

Passing a type int as a parameter

This program does not define a method named square that requires an incoming parameter of type int . However, the program calls the square method passing a value of type int as a parameter.

What happens to the int parameter?

The first question to ask is, will this cause one of the two overloaded methods to be called, or will it cause a compiler error? The answer is that itwill cause one of the overloaded methods to be called because a value of type int is assignment compatible with both type float and type double .

Which overloaded method will be called?

Since the type int is assignment compatible with type float and also with type double , the next question is, which of the two overloaded methods will be called when a value oftype int is passed as a parameter?

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
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