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Program organization

As you can see from Listing 1 , this program contains two class definitions:

  • Division01 , which is declared public .
  • Worker , which is not declared public .

As explained above, all of the source code is contained in a single disk file named Division01.java .

The class named Division01 is what I will frequently refer to as the driver class. In particular, it contains the main method, where execution begins and ends in a Java application.

A simple main method

In accordance with specification 13 of the course description , the main method is very simple. In particular, the main method instantiates a new object of the class named Worker , and calls a method named doWork belonging to that object. All of the work in the program is performed by the method named doWork .

Back to the question...

Now let's get back to the question that was posed earlier . Which of the outputs listed above are produced by the program code in Listing 1 ?

Explanation

This program illustrates the integer truncation that results when the division operator is applied to operands of the integer types.

The result of simple long division

We all know that when we divide 101 by 3, the result is 33.666666 with the sixes extending out to the limit of our arithmetic accuracy. (Confirm it using your hand calculator.)

The result of rounding

If we round the quotient to the next closest integer, the result is 34.

Integer division does not round

However, when division is performed using operands of integer types in Java, the fractional part is simply discarded (not rounded) . The result is the whole number result without regard for the fractional part or the remainder.Thus, with integer division, 101/3 produces the integer value 33.

If either operand is a floating type...

If either operand is one of the floating types,

  • the integer operand will be converted to the floating type,
  • the quotient will be of the floating type, and
  • the fractional part of the quotient will be preserved to some degree of accuracy

And the answer to the question is...

The code in Listing 1 displays 33 on the standard output device (typically the command-line screen) .

Arithmetic overflow

Let's continue with another question. What output is produced by the program shown in Listing 2 ?

  • A. Compiler Error
  • B. Runtime Error
  • C. 2147483649
  • D. -2147483647
Listing 2 . Arithmetic overflow.
public class Overflow01{ public static void main(String args[]){ new Worker().doWork();}//end main() }//end class definitionclass Worker{ public void doWork(){//Integer.MAX_VALUE = 2147483647 int myVar01 = Integer.MAX_VALUE;int myVar02 = 2; System.out.println(myVar01 + myVar02);}//end doWork() }//end class definition

Explanation

This program illustrates a dangerous situation involving arithmetic using operands of integer types. This situation involves a condition commonly known as integer overflow or arithmetic overflow . This problem usually involves either the addition or multiplication of integer operands.

The good news

The good news about doing arithmetic using operands of integer types is that as long as the result is within the allowable value range for the wider of the integer types, the results are exact (floating arithmetic often produces results that are not exact) .

Questions & Answers

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.
Damian
yes that's correct
Professor
I think
Professor
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
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
hi
Loga
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Ap computer science a, clarification of the java subset. OpenStax CNX. Oct 03, 2015 Download for free at https://legacy.cnx.org/content/col11279/1.5
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