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(A method that is declared static is commonly referred to as a class method. If the method is not declared public , it may not be accessible from your code.)

Accessing the static method

This is illustrated by the following fragment from the program, with much of the code deleted for brevity.

//... Worker.staticMethod();//... class Worker{public static void staticMethod(){ //...}//end staticMethod()}// end class

The class named Worker defines a public static method named staticMethod . A statement in the main method of the controlling class calls the method by referring to the name of theclass and the name of the method joined by a period.

When should you use static methods?

Static methods are very useful as utility methods (getting the absolute value of a number, for example) .

In my opinion, you should almost never use a static method in any circumstance that requires the storage and use of data from one call ofthe method to the next. In other words, a static method may be appropriate for use when it performs a specific task that is completed each timeit is called without the requirement for data to persist between calls.

The Math class contains many good examples of the use of static methods, such as abs , acos , asin , etc.

Back to Question 7

Answer 6

D. 3.1415927

Explanation 6

Using a public static final member variable

The class named Worker declares and initializes a member variable named fPi .

final

Because it is declared final , it is not possible to write code that will change its value after it has been initialized.

static

Because it is declared static , it can be accessed without a requirement to instantiate an object of the Worker class. All that is necessary to access the variable is to refer to the name of the classand the name of the variable joined by a period.

Because it is static , it can also be accessed by static methods.

public

Because it is declared public , it can be accessed by any code in any method in any object that can locate the class.

Type float is less precise than type double

Because the initialized value is cast from the type double that is returned by Math.PI to type float , an 8-digit approximation is stored in the variable named fPi .

The double value returned by Math.PI is 3.141592653589793

The cast to type float reduces the precision down to 3.1415927

Back to Question 6

Answer 5

C. 5

Explanation 5

Using a final local variable

Well, I finally got rid of all the bugs. This program uses a final local variable properly. The program compiles and executes without any problems.

Back to Question 5

Answer 4

A. Compiler Error

Explanation 4

The purpose of this question is to see if you are still awake.

What caused the compiler error?

The statement that caused the compiler error in this program is shown below. Now that you know that there was a compiler error, and you know which statementcaused it, do you know what caused it?

public final int x = 5;

Using public static final member variables

As I mentioned in an earlier question, the final keyword can be applied either to local variables or to member variables. When applying the final keyword to member variables, it is common practice to declare them to be both public and static in order to make them as accessible as possible. For example, the math class has a final variable that is described as follows:

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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