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What does Flanagan have to say?

Here is how David Flanagan, author of Java in a Nutshell, summarizes his discussion of member classes.

"A class defined as a member (non-static) of another. Each instance has an enclosing instance, and can use its members. New syntax for this , new , and super . Cannot have static members. Cannot have same name as containing class."

According to Flanagan, the main features of member classes are:

  • Every instance of a member class is internally associated with an instance of the class that defines or contains the member class.
  • The methods of a member class can implicitly refer to the fields defined within the member class, as well as those defined by any enclosing class,including private fields of the enclosing class.

Smoke and mirrors

Every class definition in a Java program, including nested top-level classes, member classes, local classes, and anonymous classes, produces a class file whenthe 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 member class to hold a reference to the containing object. It alsoinserts a hidden argument in all constructors for the member class, and passes the containing object's reference to the constructor for the member class. Themodified constructor saves that reference in the private instance variable of the object of the member class. Thus each object instantiated from the memberclass contains a private reference to the containing object.

Accessing private members

In those cases where it is necessary for an object of the member class to access private members of the containing object, the compiler automaticallycreates and uses accessor methods that make such access possible.

Similar to your code

The bottom line is that the code that is automatically produced by the compiler is probably very similar to code that you would write if you werewriting the program using only of top-level classes. The good news is that you don't have to write that extra code, and you don't have to maintain it. Theextra code is written for you, and if you modify your class structure, the extra code is automatically modified accordingly.

Discussion and sample code

The paragraphs that follow will explain a program named InnerClasses06 , which is designed specifically to illustrate various characteristics of memberclasses. I will discuss the program in fragments. A complete listing is shown in Listing 25 near the end of the module.

Questions & Answers

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
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
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
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
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
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
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
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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