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Back to Question 10

Answer 9

C. 10

Explanation 9

A setter and a getter

This is a very simple program that uses a setter (modifier or mutator) method named setX to set the value 10 in a property named x that is stored in an instance variable named y in an object instantiated from the class named NewClass ..

The program also uses a getter (accessor) method named getX to get and display the value of the property named x . (Note that according to JavaBeans design patterns, the name of the property isunrelated to the name of variable in which the property value is stored.)

Back to Question 9

Answer 8

D. 5

Explanation 8

Hide your data and expose your methods

For reasons that I won't go into here, good object-oriented design principles state that in almost all cases where an instance variable is not declared to be final , it should be declared private . (A final variable behaves like a constant.)

What is private access?

When an instance variable is declared private , it is accessible only by methods of the class in which it is defined. Therefore, the only way that the"outside world" can gain access to a private instance variable is by going through an (usually public ) instance method of the object.

Accessor, modifier, mutator, setter, and getter methods

Historically, methods that have been defined for the purpose of exposing private instance variables to the outside world have been referred to as accessor and modifier methods. (Modifier methods are also sometimes called mutator methods.)

(Note that since the advent of Sun's JavaBeans Component design patterns, these methods have also come to be known as getter methods and setter methods indeference to the design-pattern naming conventions for the methods.)

A private instance variable with an initializer

The class named NewClass declares a private instance variable named x and initializes its value to 2, as shown in the following code fragment:

private int x = 2;

Two constructors

The class contains both a noarg constructor and a parameterized constructor as shown in the following fragment:

public NewClass(){ }//end constructorpublic NewClass(int x){this.x = x; }//end constructor

Calling the noarg constructor

If an object of the class is instantiated by calling the noarg constructor, the initial value of 2 remains intact, and that object contains an instancevariable with an initial value of 2.

Calling the parameterized constructor

If an object of the class is instantiated by calling the parameterized constructor, the initial value of 2 is overwritten by the value of the incomingparameter to the parameterized constructor. In this case, that value is 5, because the object is instantiated by the following code fragment that passesthe literal value 5 to the parameterized constructor. Thus, the initial value of the instance variable in that object is 5.

NewClass obj = new NewClass(5);

A getter method

Because the instance variable named x is private , it cannot be accessed directly for display by the code in the makeObj method of the Worker class. However, the NewClass class provides the following public getter or accessor method that can be used to get the value stored in the instance variable.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
Ali
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..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
hey
Giriraj
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
Bhagvanji
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.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
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
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
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
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Object-oriented programming (oop) with java. OpenStax CNX. Jun 29, 2016 Download for free at https://legacy.cnx.org/content/col11441/1.201
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