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If you selected the following, you are correct:

D. Tom TOM Joe JOE Bill BILL

Similar to previous programs

The overall structure of this program is very similar to programs that I have discussed in previous modules. Therefore, I will concentrate on thoseaspects of this program that differentiate it from the programs in previous modules.

A new TreeSet object with a Comparator

The code in Listing 2 instantiates a new TreeSet object, by providing a reference to an anonymous object that implements the Comparator interface. That object is instantiated from the class named TheComparator . It is the Comparator object that will be of most interest to us in this module.

Listing 2 . A new TreeSet object with a Comparator.
Collection ref; ref = new TreeSet(new TheComparator());Populator.fillIt(ref); iter = ref.iterator();while(iter.hasNext()){ System.out.print(iter.next() + " ");}//end while loop

Populating the TreeSet collection

After the TreeSet object is instantiated, it is passed to a method named fillIt where the TreeSet collection is populated with the names of several people.

Display the contents of the TreeSet collection

As shown by the code in Listing 2 , after the TreeSet collection is populated, an Iterator is obtained for that collection and used to display the contents of the collection. The output produced by the programis shown below :


Analyzing the contents of the TreeSet collection

We will need to compare this output with the names used to populate thecollection to appreciate the true significance of the use of the Comparator object.

At this point, it is worth pointing out that the six names contained in the collection are returned by the iterator in descending order , taking the significance of upper and lower case into account. In other words, namesbeginning with letters that are high in the alphabet occur before names beginning with letters that are lower in the alphabet. In addition, namescontaining lower case characters appear before the same names containing only upper case characters.

Method used to populate the collection

Listing 3 shows the method named fillIt that was used to populate the collection with references to six String objects. As you can see, the names weren't added in any particular order.

As you can also see by comparing Listing 3 with the output shown above , all six names that were added to the collection were displayed in the output, but ina different order from the order in which they were added. (Names with the same spelling but different case were not considered to be duplicates insofar asthe contract for the set was concerned.)

Listing 3 . The fillIt method.
public static void fillIt(Collection ref){ ref.add("Joe");ref.add("Bill"); ref.add("Tom");ref.add("JOE"); ref.add("BILL");ref.add("TOM"); }//end fillIt()

Implementing the Comparator interface

That brings us to the class from which the Comparator object was instantiated. The beginning portion of that class is shown in Listing 4 .

Listing 4 . Beginning of the class named TheComparator.
class TheComparator implements Comparator,Serializable{public int compare(Object o1,Object o2){ if(!(o1 instanceof String))throw new ClassCastException(); if(!(o2 instanceof String))throw new ClassCastException();

Questions & Answers

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.
yes that's correct
I think
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
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
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
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 did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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