<< Chapter < Page Chapter >> Page >

Create and populate an array holding references to audio objects

Listing 2 begins by creating an array capable of holding references to eight audio objects instantiated from subclasses of the AudioSignalGenerator02 class. Note that the type of each element in this array is AudioSignalGenerator02 .

Then Listing 2 populates the array elements with references to eight different audio objects instantiated from those classes. Even though an object may beinstantiated from the class named FMSweep , for example, that object's reference is being stored as type AudioSignalGenerator02 .

Listing 2 . Create and populate an array holding references to audio objects.
AudioSignalGenerator02[] audioObjects = new AudioSignalGenerator02[8];audioObjects[0] = new AudioGraphSinusoidal(audioParams,this.args,melody);audioObjects[1] = new AudioGraphSquareWave(audioParams,this.args,melody);audioObjects[2] = new FMSweep(audioParams,this.args,melody);audioObjects[3] = new SquareWave(audioParams,this.args,melody);audioObjects[4] = new StereoPingpong(audioParams,this.args,melody);audioObjects[5] = new ToneMono(audioParams,this.args,melody);audioObjects[6] = new TonesStereo(audioParams,this.args,melody);audioObjects[7] = new WhiteNoise(audioParams,this.args,melody);

Override an inherited abstract method

The abstract class named AudioSignalGenerator02 declares an abstract method named getMelody . Each subclass of the abstract class must define a concrete version of (override) the inherited abstract method or the subclass itself be declared abstract.

All eight of the subclasses listed in Listing 2 override the getMelody method. The behavior of each overridden version of the method is significantly different from one class to the next.

When the getMelody method is called on a reference to a subclass object that is stored as the superclass type, the resulting behavior isthat of the subclass method and not that of the superclass method. That is runtime polymorphism.

Call the getMelody method on a subclass object selected at random

Listing 3 selects a reference to an audio object at random and calls the getMelody method on the object. As in previous modules, the reference to the byte array returned by the method is saved in the byte[] variable named melody . Unlike before, however, at this point, we don't know what melody was saved there. We only know thatit will be one of eight possible melodies and we won't know which one until we actually play the melody. (At least that would be true if the code in Listing 3 didn't access and print the type of the object pointed to by the random index.)

Listing 3 . Call the getMelody method on a subclass object selected at random.
Random randomGenerator = new Random(); int randomIndex = randomGenerator.nextInt(8);System.out.println("randomIndex = " + randomIndex); System.out.println(audioObjects[randomIndex].getClass());melody = audioObjects[randomIndex].getMelody();

Some new melodies

The following melodies are new to this module:

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
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
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
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
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get the best Algebra and trigonometry course in your pocket!





Source:  OpenStax, Accessible objected-oriented programming concepts for blind students using java. OpenStax CNX. Sep 01, 2014 Download for free at https://legacy.cnx.org/content/col11349/1.17
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Accessible objected-oriented programming concepts for blind students using java' conversation and receive update notifications?

Ask