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Thus, it is possible to define an anonymous class that extends a class whose constructor requires parameters, and to pass those parameters to the superclassconstructor when the anonymous class is instantiated.

The parentheses following interfaceName in the second expression in Figure 1 must always be empty. In this case, the superclass is always Object , which never expects constructor parameters.

Discussion and sample code

The paragraphs that follow will explain a program named InnerClasses08 . This program is designed specifically to illustrate anonymous classes, and to compareanonymous classes with local classes.

I will discuss the program in fragments. A complete listing of the program is provided in Listing 10 .

When the program is executed, it produces the GUI shown in Figure 2 . I will refer back to this image during the discussion of the program.

Class file names

This program consists of a total of six classes:

  • Two top-level classes
    • InnerClasses08.class
    • GUI.class
  • One local class
    • GUI$1$BaldButton.class
  • Three anonymous classes
    • GUI$1.class
    • GUI$2.class
    • GUI$3.class

When compiled, the program produces the class files shown in Figure 3 .

(As you can see, the anonymous classes are not truly anonymous, since the files that represent them must have names. Generally, however, theestablishment of the individual names is beyond the control of the programmer, and the names are not known to the program in a way that makesit possible to refer to them by name.)

Program structure and behavior

This program is designed to illustrate the use of local classes and anonymous classes in a very practical way. Itillustrates one implementation of a local class and three different implementations of anonymous classes. The program compares the local class withan anonymous class designed to accomplish the same purpose. The program also illustrates the use of instance initializers as an alternative toconstructors.

A local class

The program defines and uses a local class to instantiate an object to handle mouse clicked events on a button with low-level event handling. This class uses a constructor to enable mouse events on a newextended Button class. It also uses a constructor to display the name of the class file.

Three anonymous classes

An anonymous class to compare with the local class

The program also defines and uses an anonymous class to instantiate an object tohandle mouse clicked events on a button with low-level event handling.

This class uses an instance initializer to enable mouse events on a new extended Button class. It also uses an instance initializer to display the name of the class file.

This class and the local class described above provide a direct comparison between the use of local classes and anonymous classes toserve the same purpose.

An anonymous class that implements an interface

The program illustrates the use of an anonymous class that implements the MouseListener interface, to instantiate an object to handle mouse clicked events using the source-listener event model (sometimes referred to as the delegation event model or the JavaBeans event model). The anonymous class uses an instance initializer to display the name of the class file.

Questions & Answers

anyone know any internet site where one can find nanotechnology papers?
Damian Reply
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.
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
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
characteristics of micro business
for teaching engĺish at school how nano technology help us
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
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
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.
what is the actual application of fullerenes nowadays?
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.
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.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
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.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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