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A software framework, in computer programming, is an abstraction in which common code providing generic functionality can be selectivelyoverridden or specialized by user code providing specific functionality.

Frameworks are a special case of software libraries in that they are reusable abstractions of code wrapped in a well-defined API, yet they contain some keydistinguishing features that separate them from normal libraries.

Software frameworks have these distinguishing features that separate them from libraries or normal user applications:

  1. inversion of control - In a framework, unlike in libraries or normal user applications, the overall program's flow of controlis not dictated by the caller, but by the framework.
  2. default behavior - A framework has a default behavior. This default behavior must actually be some useful behavior and not a seriesof no-ops.
  3. extensibility - A framework can be extended by the user by selective overriding of framework code in order to provide specificfunctionality
  4. non-modifiable framework code - The framework code, in general should not normally be modified by the user. Users can extend theframework, but normally should not modify its code.

In short, a software framework is a computer program that helps you to write computer programs.

The Processing PDE fits all of these characteristics of a framework.

Inversion of control

By default, the overall flow of control of a Processing sketch is beyond the control of the programmer. When the sketch starts running, the setup method will be called once and (by default) the draw method will be called repeatedly at a default rate of 60 calls per second.

A small window will be displayed in the default Java display mode. If you haven't overridden the draw method to control the contents of that window, it will look something like that shown in Image 1 .

Image 1. default display window.

Default display window
Image 1. Default display window.

Create the body of a class

Image 2 shows a screen shot of the PDE with program code showing in the leftmost tab.

Image 2. the pde.

The PDE.
Image 2. The PDE.

When you create a new sketch in the PDE and enter code in the leftmost tab, you are actually writing the body of a new class witha class name that matches the name of the tab. The code that you see in Image 2 , for example, constitutes the body of a new class named Cars .

Override setup and draw methods

In general, you need to override the methods named setup and draw in the body of this class. It is the code that you write in these two overridden methods that controls the behavior of the sketch.

The setup method will be called once when you click the run button. You should place any code that needs to be executed to initialize the state of the sketch in this method. Often this code willinitialize variables, instantiate new objects, etc.

After that, by default, the draw method will be called repeatedly until you terminate execution of the sketch. You need to write codein the draw method that controls the ongoing behavior of the sketch. Often, this code will call methods on existing objects, modify thecontents of variables, instantiate and call methods on new objects, etc.

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
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
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, The processing programming environment. OpenStax CNX. Feb 26, 2013 Download for free at http://cnx.org/content/col11492/1.5
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