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Explanation 7

Not the same as C and C++

Unlike C and C++, which can use an integer numeric expression in the conditional clause of an if statement, Java requires the conditional clause of an if statement to contain an expression that will return a boolean result.

Bad conditional expression

That is not the case in this program, and the following compiler error occurs under JDK 1.3:

Ap031.java:13: incompatible types found : intrequired: boolean if(x - y){

Back to Question 7

Answer 6

D. 6 4 9.3 7.300000000000001

Explanation 6

Postfix increment and decrement operators

This program illustrates the use of the increment (++) and decrement (--) operators in their postfix form.

Behavior of increment operator

Given a variable x , the following two statements are equivalent:

x++; x = x + 1;

Behavior of decrement operator

Also, the following two statements are equivalent:

x--; x = x - 1;

Prefix and postfix forms available

These operators have both a prefix form and a postfix form.

Can be fairly complex

It is possible to construct some fairly complex scenarios when using these operators and combining them into expressions.

In these modules ...

In this group of self-assessment modules, the increment and decrement operators will primarily be used to update control variables in loops.

Inaccurate results

Regarding the program output, you will note that there is a little arithmetic inaccuracy when this program is executed using JDK 1.3. (The same is still true with JDK version 1.7.)

Ideally, the output value 7.300000000000001 should simply be 7.3 without the very small additional fractional part, but that sort of thing often happens whenusing floating types.

Back to Question 6

Answer 5

A. Compiler Error

Explanation 5

Cannot use>with reference variables

The only relational operator that can be applied to reference variables is the == operator.

As discussed in the previous questions, even then it can only be used to determine if two reference variables refer to the same object.

This program produces the following compiler error under JDK 1.3:

Ap029.java:14: operator>cannot be applied to Dummy,Dummy System.out.println(x>y);

Back to Question 5

Answer 4

E. true true

Explanation 4

Two references to the same object

In this case, the reference variables named x and y both refer to the same object. Therefore, when tested for equality, using either the ==operator or the default equals method, the result is true.

Back to Question 4

Answer 3

D. false

Explanation 3

Read question 2

In case you skipped it, you need to read the explanation for the answer to Question 2 before reading this explanation.

Objects appear to be equal

These two objects are of the same type and contain the same values. Whyare they reported as not being equal?

Did not override the equals method

When I defined the class named Dummy used in the programs for Question 2 and Question 3 , I did not override the method named equals .

Therefore, my class named Dummy simply inherited the default version of the method named equals that is defined in the class named Object .

Questions & Answers

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
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
characteristics of micro business
Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
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.
what is the actual application of fullerenes nowadays?
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.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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