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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

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
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
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
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.
Bharti
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
Daniel
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
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
How can I make nanorobot?
Lily
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
NANO
how can I make nanorobot?
Lily
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
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.
Tarell
what is the actual application of fullerenes nowadays?
Damian
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.
Tarell
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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