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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

where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
Ali
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
hey
Giriraj
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
Bhagvanji
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.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
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
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
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?
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
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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