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And the answer is ...

The correct answer to the quiz is the program output shown below:

Collection contents B0 B1 L2 B3 B4 L5New array contents B0 B1 L2 B3 B4 L5Modified array contents XX B1 L2 B3 B4 L5Collection contents XX B1 L2 B3 B4 L5

If that was your answer, you probably already understand most of the material covered in this module. In that case, you might consider skipping this moduleand moving on to the next module. If that wasn't your answer, you should probably continue with your study of this module.

A new LinkedList collection

The code in Listing 2 creates and populates a new LinkedList object and saves the object's reference as the interface type Collection . The collection is populated by passing the LinkedList object's reference to a method named fillIt .

The code in Listing 2 also displays the contents of the LinkedList after it has been populated. The list is displayed by passing the LinkedList object's reference to a method named showCollection .

Listing 2 . A new LinkedList collection.
Collection ref; ref = new LinkedList();Populator.fillIt(ref); System.out.println("Collection contents");showCollection(ref);

The LinkedList class

The LinkedList class is one of the concrete class implementations of the Collections Framework . This class implements the Collection interface and the List interface. Thus, it adheres to the contracts and stipulations of the List interface.

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

"Linked list implementation of the List interface. Implements all optional list operations, and permits all elements (including null). Inaddition ..."

Populating the LinkedList collection

The beginning of the static fillIt method, used to populate the collection, is shown in Listing 3 .

Listing 3 . Beginning of the fillIt method.
public static void fillIt(Collection ref){ ref.add(new JButton());ref.add(new JButton()); ref.add(new JLabel());ref.add(new JButton()); ref.add(new JButton());ref.add(new JLabel());

As shown in Listing 3 , the fillIt method begins by calling the add method six times in succession, passing references to new anonymous objects as aparameter to the add method.

Four buttons and two labels

Four of the objects are instantiated from the class named JButton . Two of the objects are instantiated from the class named JLabel .

Both JButton and JLabel belong to the javax.swing package. Further, both are subclasses of the class named JComponent .

The toolTipText property

Finally, both classes have a property named toolTipText , which can be set and accessed by calling the following methods on a reference to the object:

void setToolTipText(String text)String getToolTipText()

Why am I using Swing GUI components?

I really don't plan to do anything special with these Swing GUI components. Rather, I chose to use them for illustration purposes simply becausethey possess the characteristics that I need for this module, and the nextmodule as well. Those characteristics are:

  • Both classes subclass the class named JComponent (a common superclass below the Object class).
  • Both classes inherit a property (toolTipText) that can be used to identify them later.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
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
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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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