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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 to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
can nanotechnology change the direction of the face of the world
Prasenjit Reply
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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