# 7.4 Ap0040: self-assessment, logical operations, numeric casting,  (Page 6/8)

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Two String operands

If both operands are references to objects of type String , the plus operator creates and returns a new String object that contains the concatenated values of the two operands.

One String operand and one of another type

If one operand is a reference to an object of type String and the other operand is of some type other than String , the plus operator causes a new String object to come into existence.

This new String object is a String representation of the non-String operand (such as a value of type int ) ,

Then it concatenates the two String objects, producing another new String object, which is the concatenation of the two.

How is the new String operand representing the non-string operand created?

The manner in which it creates the new String object that represents the non-String operand varies with the actual type of the operand.

A primitive operand

The simplest case is when the non-String operand is one of the primitive types. In these cases, the capability already exists in the core programminglanguage to produce a String object that represents the value of the primitive type.

A boolean operand

For example, if the operand is of type boolean , the new String object that represents the operand will either contain the word true or the word false.

A numeric operand

If the operand is one of the numeric types, the new String object will be composed of some of the following:

• numeric characters
• a decimal point character
• minus characters
• plus character
• other characters such as E or e

These characters will be arranged in such a way as to represent the numeric value of the operand to a human observer.

In this program ...

In this program, a numeric double value, a numeric int value, and a boolean value were concatenated with a pair of slash characters to produce a String object containing the following:

3.5/9/true

When a reference to this String object was passed as a parameter to the println method, the code in that method extracted the character string from the String object, and displayed that character string on the screen.

The toString method

If one of the operands to the plus operator is a reference to an object, the toString method is called on the reference to produce a string that represents the object. The toString method may be overridden by the author of the class from which the object was instantiated toproduce a String that faithfully represents the object.

C. 4 -3

## Explanation 6

A rounding algorithm

The method named doIt in this program illustrates an algorithm that can be used with a numeric cast operator (int) to cause double values to be rounded to the nearest integer.

Different than truncation toward zero

Note that this is different from simply truncating to the next integer closer to zero (as was illustrated in Question 5 ) .

D. 3 -3

## Explanation 5

Truncates toward zero

When a double value is cast to an int , the fractional part of the double value is discarded.

This produces a result that is the next integer value closer to zero.

This is true regardless of whether the double is positive or negative. This is sometimes referred to as its "truncation toward zero" behavior.

How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
what is Nano technology ?
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?
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
why we need to study biomolecules, molecular biology in nanotechnology?
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
why?
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?
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
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Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
it is a goid question and i want to know the answer as well
Maciej
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?
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
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
what is the Synthesis, properties,and applications of carbon nano chemistry
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
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