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Factories are a natural partner with anonymous inner classes. With a factory that returns anonymous inner classes, we can instantiate unique objects with unique behaviors. If the factory method takes in parameters, there local variables can be used to alter the resultant object's behavior, a process called " currying " (named after the famous mathematician/computer scientist Haskell Curry ). The objects made by the factory are then sent off to various odd and sundry different parts of our OO system but all the while retaining their closures, which were determined at the time of their instantiation. Thus they retain the ability to communicate back to the factory that made them even though they are being used in another part of the system that knows nothing about the factory. We like to call these " spy objects " because they act like spies from the factory. This gives us powerful communications even though the system is decoupled.

This is the last piece of our abstraction puzzle! We have

  1. Abstract Structure -- abstract classes, interfaces
  2. Abstract Behavior -- abstract methods, strategies, visitors.
  3. Abstract Construction -- factories
  4. Abstract Environments -- anonymous inner classes, closures.

Examples

Example 1: reversing a list using factory and anonymous inner class helper

Write Reverse such that it takes one parameter, the IListFactory , but such that its helper only takes one parameter (other than the host list) which is the accumulated list.

public class Reverse implements IListAlgo {public static final Reverse Singleton = new Reverse();private Reverse() {}public Object emptyCase(IMTList host0, Object... fac) { return ((IListFactory)fac[0]).makeEmptyList(); }public Object nonEmptyCase(INEList host0, Object... fac) {final IListFactory f = (IListFactory) fac[0]; // final so that the anon. inner// class can access it.return host0.getRest().execute(new IListAlgo() {public Object emptyCase(IMTList host1, Object... acc) { return acc[0]; }public Object nonEmptyCase(INEList host1, Object... acc) {return host1.getRest().execute(this, f.makeNEList(host1.getFirst(), (IList) acc[0])); }},f.makeNEList(host0.getFirst(), f.makeEmptyList())); }}

Example 2: ant world

Imagine a world of ants that live in a one-dimensional space. A queen ant can make a bunch of worker ants. Each time she gives birth to a worker ant, she gives it a name. A worker ant can always tell what its name is. A worker ant from a particular colony can always calculate its distance from its queen. A worker ant can also move its queen to a different location. Wherever the queen moves to, ALL of her workers always know their relative distance from her. We want to keep track of all the ants in our ant world and all the ants in each of the existing colonies. We want to model the fact that each queen produces its own worker ants, each one which can move its queen around without telling the other ants in the same colony, yet ALL of the ants in the same colony would know where their queen is.

Questions & Answers

how can chip be made from sand
Eke Reply
are nano particles real
Missy Reply
yeah
Joseph
Hello, if I study Physics teacher in bachelor, can I study Nanotechnology in master?
Lale Reply
no can't
Lohitha
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
has a lot of application modern world
Kamaluddeen
yes
narayan
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
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Principles of object-oriented programming. OpenStax CNX. May 10, 2013 Download for free at http://legacy.cnx.org/content/col10213/1.37
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