<< Chapter < Page Chapter >> Page >

The bottom line is that with socket programming, it is easy to write code that will cause a stream of bytes to flow in both directions between a clientand a server. This is no more difficult than causing a stream of bytes to flow in both directions between memory and a file on a disk.

However, getting the bytes to flow is the easy part. Beyond that, you must do all of the programming to implement an application protocol that is understoodby both the client and the server.

URL Programming

URL programming occurs at a higher level than socket programming, and in theory represents a very powerful idea.

In theory, by using the URL class, you can open a connection to a resource on the web, specified by a URL object, and simply call the getContent method on that URL object. The content of the resource will then be magically downloaded and will appear as an object on the clientmachine, even if it requires an application protocol that didn't exist when you wrote the program, and contains content that you didn't understand when youwrote the program.

This description may be a bit of an overstatement, but it is pretty close to the claims being made. This is a powerful idea, which may or may not bear fruitin the future.

If fully implemented by browsers, the idea means that you can place new and unusual material on a web site along with special content handlers and protocolhandlers. Then a cooperating browser will use those special handlers to move that material from the web site to the client and interpret its content once itgets there without a requirement to install software (such as plug-ins) on the client computer on a permanent basis.

Here is what Peter van der Linden has to say about this topic in his excellent book titled Just Java 1.1 and Beyond:

"If a browser doesn't recognize a media type, it should be able to download the code to process it from the same place it got the file. If theyever get this working, it will be ... a good thing."

Is it working, or will they ever get it working? I don't know. If it depends on cooperation among all the major players, including the major browser vendors- probably not. Therefore, I don't plan to spend much time on the topic of protocol and content handlers until I see some evidence that it is working tosuch an extent that it is practically useful.

That is not to say that you couldn't use the capability right now if you were developing an intranet and wanted the clients to have access to new and unusualcontent. It would be necessary for you to provide the appropriate protocol and content handlers, and it would probably be necessary for the clients to run Javaapplications written by you instead of standard browsers to access the data.

Also, the URL class provides an alternative way to connect one computer to another and transfer data on a stream basis, so we will see someexamples of retrieving data from a server by obtaining a URL connection, and then opening and servicing I/O streams between the client and the server. Wewill see some sample programs that make use of this technique, but we will also see that it is somewhat redundant with the socket programming approach.

A local area network

This is part of a sub-collection of modules designed for teaching network programming. Therefore, you may find some of the modules more meaningful if youare able to connect two or more computers in a local area network and run the sample programs across the network.

However, it is possible to simulate a network inside a single computer. If you are unable to create an actual network, you should be able to run all of thesample programs by simulating a network in your single computer.

The operating system

While the capabilities of Java are generally independent of the operating system in use, the manner in which an individual computer must be configured fornetwork operation is generally not independent of the operating system.

In those cases where these modules provide instructions for configuring the computer, those instructions will assume a Windows operating system. If you areusing a different operating system, you will need to translate those instructions into your operating system.

What's Next?

We will learn how to use the Java InetAddress class to find the domain name corresponding to an IP address, and to find the IP addresscorresponding to a domain name in our sample program in the next module.


This section contains a variety of miscellaneous information.

Housekeeping material
  • Module name: Java4620: General Information
  • File: Java4620.htm
  • Published: 03/02/14
  • Revised 12/26/14

Financial : Although the Connexions site makes it possible for you to download a PDF file for thismodule at no charge, and also makes it possible for you to purchase a pre-printed version of the PDF file, you should beaware that some of the HTML elements in this module may not translate well into PDF.

I also want you to know that, I receive no financial compensation from the Connexions website even if you purchase the PDF version of the module.

In the past, unknown individuals have copied my modules from cnx.org, converted them to Kindle books, and placed them for sale on Amazon.com showing me as the author. Ineither receive compensation for those sales nor do I know who does receive compensation. If you purchase such a book, please beaware that it is a copy of a module that is freely available on cnx.org and that it was made and published without my prior knowledge.

Affiliation : I am a professor of Computer Information Technology at Austin Community College in Austin, TX.


Questions & Answers

how can chip be made from sand
Eke Reply
are nano particles real
Missy Reply
Hello, if I study Physics teacher in bachelor, can I study Nanotechnology in master?
Lale Reply
no can't
where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
has a lot of application modern world
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
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.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
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
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
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
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
Privacy Information Security Software Version 1.1a
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get Jobilize Job Search Mobile App in your pocket Now!

Get it on Google Play Download on the App Store Now

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
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Object-oriented programming (oop) with java' conversation and receive update notifications?