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Sorting the array into natural order

The code in Listing 8 is also new to this module. This code uses one of the overloaded sort methods of the Arrays class to sort the contents of the array into natural order .

Listing 8 . Sorting the array into natural order.

Here is part of what Oracle has to say about the Arrays class:

"This class contains various methods for manipulating arrays (such as sorting and searching)."

The class contains many overloaded versions of the sort method. Here is part of what Oracle has to say about the version of the sort method used in Listing 8 above:

"Sorts the specified array of objects into ascending order, according to the natural ordering of its elements. All elements in the array mustimplement the Comparable interface."

The Comparable interface and polymorphic behavior

Although the declared type of the array is Object , the array actually contains references to String objects.

The String class implements the Comparable interface. It is not necessary to cast the array to type String before passing it to the Sort method. (The Sort method declares the incoming parameter as type Object .)

The sort method treats the array elements as type Comparable and uses the compareTo method declared in that interface to perform any necessary comparisons required to carry out the sorting operation.

This is another example of the usefulness of polymorphism as implemented through the use of the Java interface. (The Comparable interface and the compareTo method declared in that interface were discussed in detail in an earlier module.)

Display the sorted array data

The code in Listing 9 displays the contents of the array after those contents are sorted into natural order by the sort method in Listing 8 above.

Listing 9 . Display the sorted array data.
System.out.println("Natural order sorted " + "array data");display(array);

The output produced by Listing 9 above is:

Natural order sorted array data BILL Bill JOE Joe TOM Tom

The natural order for String objects

I discussed the concept of natural ordering in a previous module with particular emphasis of the natural order for strings. You will recognize that the strings shown in the above output have been sorted into natural order according to the definition of the compareTo method of the String class.

Sort the array with a Comparator

The code in Listing 10 is also new to this module. This code uses a different version of the overloaded sort method of the Arrays class to sort the array using the rules defined in the compare method of a Comparator object (passed as a parameter to the sort method).

Listing 10 . Sort the array with a Comparator.
Arrays.sort(array, new TheComparator());

What does Oracle have to say about this?

Here is part of what Oracle has to say about this version of the sort method of the Arrays class:

"Sorts the specified array of objects according to the order induced by the specified comparator. All elements in the array must be mutuallycomparable by the specified comparator (that is, c.compare(e1, e2) must not throw a ClassCastException for any elements e1 and e2 in the array)."

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
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
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
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.
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
for teaching engĺish at school how nano technology help us
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
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?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
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
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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