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A higher level approach

URL programming occurs at a higher level than socket programming, and in theory represents some very powerful ideas. The powerful ideas represented bythe advanced features of the URL class require an understanding of the development of protocol handlers and content handlers. I discussed this in somedetail in an earlier module titled Java4620: General Information , and won't repeat that discussion here.

A mundane alternative

In addition to supporting the advanced concepts discussed in the earlier module, theURL class also provides a relatively mundane alternative way to connect one computer to another and transfer data on a stream basis. This module isprimarily based on this capability.

Discussion and sample code

I will explain the programs named Java4640a and Java4640d in fragments. Complete listings of both programs are provided in Listing 8 and Listing 9 .

The program Java4640a

This program exercises four of the constructors and six of the methods of the URL class.

The program also illustrates the use of the URLEncoder class to convert a string containing spaces and other such characters into a UTF-8encoded string format.

Screen output from the program named Java4640a

The output from the program is shown in Figure 2 . I will refer to portions of this output while discussing the program.

Figure 2 - Screen output from the program named Java4640a.
Use simple string constructor for host URL http www.austincc.edu -1 nullhttp://www.austincc.edu Use simple string constructor for host plus filehttp www.austincc.edu -1 /baldwin null http://www.austincc.edu/baldwinUse strings for protocol, host, and file http www.austincc.edu -1 /baldwin nullhttp://www.austincc.edu/baldwin Use strings for protocol host, and fileand int for port http www.austincc.edu 80 /baldwin nullhttp://www.austincc.edu:80/baldwin Construct absolute URL from host URL and relative URLhttp www.austincc.edu -1 /baldwin/Index.html null http://www.austincc.edu/baldwin/Index.htmlNow use URLEncoder to create UTF-8 encoded String http://space .tilde~.plus+.comhttp%3A%2F%2Fspace+.tilde%7E.plus%2B.com

The method named display

The code in Listing 1 is a method named display that I wrote to illustrate some of the methods of the URLclass, and also to serve the practical needs of displaying information contained in a URL object.

Listing 1 - The method named display.
void display(URL url){//method to display parts of URL System.out.print(url.getProtocol() + " ");System.out.print(url.getHost() + " "); System.out.print(url.getPort() + " ");System.out.print(url.getFile() + " "); System.out.println(url.getRef());//Now display entire URL as a string.System.out.println(url.toString()); System.out.println();}//end display

This method receives a reference to a URL object as a parameter and displays its component parts separated by space characters. Then it uses the overridden toString method of the URL class to display the contents of theURL object as a single String object.

The parts of the URL

Questions & Answers

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.
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
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
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
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
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
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
How can I make nanorobot?
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