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Then the program closes the socket and terminates.

Simple browser program

The next program is an extremely simple web browser program. More correctly, the next program is a simple HTTP client implemented using sockets. A completelisting of the program is provided in Listing 14 .

The program implements just enough of the HTTP protocol to make it capable of getting a file froman HTTP server. Considerably more programming effort would be required to turn it into a useful browser.

Beginning of the program named Java4660c

As shown in Listing 8 , the program begins by defining the name of a server and the number of the HTTP port on that server. Although the standard portnumber for HTTP servers is port 80, this program is written to access a Tomcat server as localhost using port 8080.

Listing 8 - Beginning of the program named Java4660c.
import java.net.*; import java.io.*;class Java4660c{ public static void main(String[]args){ String server = "localhost";int port = 8080; //http port on localhost try{//Get a socket, connected to the specified server // on the specified port.Socket socket = new Socket(server,port);

Then the program opens a socket to the specified server on the specified port.

Create input and output streams

As shown in Listing 9 , the program creates input and output stream objects for transferring data between the client and the server .

Listing 9 - Create input and output streams.
//Get an input stream from the socket BufferedReader inputStream =new BufferedReader(new InputStreamReader( socket.getInputStream()));//Get an output stream to the socket. Note // that this stream will autoflush.PrintWriter outputStream = new PrintWriter(new OutputStreamWriter(socket.getOutputStream()),true);

The output stream will autoflush , which is critical. If the output stream isn't flushed, the server will not respondproperly. (Presumably it may not receive all of the data until the stream is flushed.)

Send a GET command

The HTTP protocol provides several different commands or requests that the client can send to the server. This program implements only the GET command. This is a request by the client to find and download a specified file.

Then, as shown in Listing 10 , acting as an HTTP client, the program sends a GET command to the server specifying a particular path and file name. The GET command is part of the HTTP application protocol.

Listing 10 - Send a GET command.
outputStream.println("GET /Java4570b.jsp");

Fetch and send

This causes the server to attempt to fetch the specified file and send it to the client. If the server is being properly supported on the specific port, itwill send something, although that something could be an error message.

Note that the request includes not only the file name, but also the path to that file relative to the directory that the HTTP server software considers tobe the pseudo-root . This is probably not the actual root directory on the server computer, but rather is a logical root.

Questions & Answers

what is variations in raman spectra for nanomaterials
Jyoti Reply
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.
Damian
yes that's correct
Professor
I think
Professor
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
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
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
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 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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