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The methods of a local class can use any final local variables or method parameters that are visible from the scope in which the local class isdefined.

Similar to member classes

As mentioned earlier, local classes have many characteristics in common with member classes. This includes access to private fields and methods in thecontaining class. The thing that separates local classes from member classes is the fact that local classes have access to local variables in the scope in whichthe local class is defined.

A big restriction

There is a big restriction, however, on the ability of methods of the local class to access local variables and method parameters. The methods in a localclass can access local variables and method parameters only if they are declared final .

What does Flanagan have to say?

According to one of my favorite authors, David Flanagan, author of Java in a Nutshell, the methods in a local class don't really have access to localvariables and method parameters. Rather, when an object of the local class is instantiated, copies of the final local variables and method parameters referred to by the object's methods are stored as instance variables in theobject. The methods in the object of the local class really access those hidden instance variables. (See the later section entitled Smoke and mirrors.)

Thus, the local variables and method parameters accessed by the methods of the local class must be declared final to prevent their values from changing after the object is instantiated.

Restrictions on local classes

As with member classes, local classes cannot contain static members.

As with local variables, local classes cannot be declared public , protected , private , or static .

A local class cannot have the same name as any of its enclosing classes.

Smoke and mirrors

As I mentioned in the previous module, every class definition in a Java program, including nested top-level classes, member classes, local classes, andanonymous classes, produces a class file when the program is compiled. According to Flanagan,

"The Java Virtual Machine knows nothing about nested top-level classes and interfaces or the various types of inner classes. Therefore, the Javacompiler must convert these new types into standard non-nested class files that the Java interpreter can understand. This is done through source codetransformations that insert $ characters into nested class names. These source code transformations may also insert hidden fields, methods, andconstructor arguments into the affected classes."

A reference to the containing object

For example, the compiler automatically inserts a private instance variable in the local class to hold a reference to the containing object. It also insertsa hidden argument in all constructors for the local class, and passes the containing object's reference to the constructor for the local class. Themodified constructor saves that reference in the private instance variable of the object of the local class. Thus each object instantiated from the localclass contains a private reference to the containing object.

Questions & Answers

how can chip be made from sand
Eke Reply
is this allso about nanoscale material
Almas
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 is the latest information on a no technology how can I find it
William
currently
William
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
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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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