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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

find the 15th term of the geometric sequince whose first is 18 and last term of 387
Jerwin Reply
I know this work
The given of f(x=x-2. then what is the value of this f(3) 5f(x+1)
virgelyn Reply
hmm well what is the answer
how do they get the third part x = (32)5/4
kinnecy Reply
can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
okay, so you have 6 raised to the power of 2. what is that part of your answer
I don't understand what the A with approx sign and the boxed x mean
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
I'm not sure why it wrote it the other way
I got X =-6
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
oops. ignore that.
so you not have an equal sign anywhere in the original equation?
is it a question of log
I rally confuse this number And equations too I need exactly help
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Commplementary angles
Idrissa Reply
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what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
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Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris 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
what is nano technology
Sravani Reply
what is system testing?
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
what is system testing
what is the application of nanotechnology?
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
anybody can imagine what will be happen after 100 years from now in nano tech world
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
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele 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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