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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

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
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.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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