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Specialized for type MyClass

This Comparator is specialized to compare two objects of the class named MyClass . The first two statements in Listing 6 above confirm that both of the incoming objects are of type MyClass . If either object is not of that type, an exception is thrown.

General behavior of compare method

The general description of the behavior of the compare method as provided by Oracle is shown below:

"Compares its two arguments for order. Returns a negative integer, zero, or a positive integer as the first argument is less than, equal to, orgreater than the second."

Implementation of required behavior

This behavior is accomplished by the code shown in Listing 7 . In this case, the comparison is based solely on the values of the instance variablenamed data in each of the two objects.

Depending on which object contains the larger value in its instance variable, a value of 1 or -1 is returned. If the two values are equal, a value of 0is returned.

(Note that it is up to the author of the compare method to decide what constitutes larger. This gives the author of themethod a great deal of control over the results of a sorting operation.)
Listing 7 . Implementation of required behavior.
if(((MyClass)o1).data<((MyClass)o2).data) return -1;if(((MyClass)o1).data>((MyClass)o2).data) return 1;else return 0; }//end compare()

Other stipulations

The documentation for the compare method contains several other stipulations regarding the behavior of the method. While I believe thatthis version of the compare method meets all of those stipulations, I haven't taken the time to test it fully. Therefore, it is possible that itmay not meet all of the stipulations in terms of its behavior.

The equals method

Every new class inherits a default version of the equals method from the class named Object. Therefore, a new class that implements the Comparator interface already has such a method. The new class is free to override the inherited version, or to simply make use of the inheritedversion. Here is what Oracle has to say on the subject:

"Note that it is always safe not to override Object.equals(Object). However, overriding this method may, in some cases, improve performance byallowing programs to determine that two distinct Comparators impose the same order."

Overridden equals method

I decided, for purposes of illustration, to go ahead and override the equals method. However, my overridden version, as shown in Listing 8 isn't very significant. It simply confirms that an object being comparedfor equality to a Comparator object is instantiated from the same class.

Since the Comparator object doesn't contain any instance variables, there isn't much more to be tested for equality.

Listing 8 . The overridden equals method.
public boolean equals(Object o){ if(!(o instanceof TheComparator))return false; else return true;}//end overridden equals() }//end class TheComparator

The program output

Finally, the code shown in Listing 9 uses an Iterator to display the contents of the populated TreeSet object.

Questions & Answers

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
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
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
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.
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
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.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
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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