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Figure 6 - Encoding rules.

To convert a String, each character is examined in turn:

The ASCII characters 'a' through 'z', 'A' through 'Z', and '0' through '9' remain the same.

The space character ' ' is converted into a plus sign '+'.

All other characters are converted into the 3-character string "%xy", where xy is the two-digit hexadecimal representation of the lower 8-bits of the character.

Elliotte Rusty Harold provides a URLDecoder class in his Java Network Programming book that takes a URL string in the format shown above and converts it back toits String representation.

The program Java4640d

Now it is time to put some of what you have learned to work with a program named Java4640d . Once again, I will explain this program in fragments. A complete listing is provided in Listing 9 .

This program illustrates using a URL object to connect to a URL and to read a file from that URL as an input stream. As we will see later, we can and will do the same thing using sockets in future modules.

Your computer must be online for this program to run properly. Otherwise, it will throw an exception of type UnknownHostException .

Program output

The output from the program is a display of the contents of the file named page1.html in a raw text format. Thus, all of the HTML tags are visible.

(Of course, you can modify the program to download and display a different file on the same or a different website.)

As of January 2014, the output for the beginning of the file was as shown in Figure 7 . (The file is much longer than that shown.)

(I may modify the contents of this file from time to time, so if you compile and run this program later, you may get different results.)
Figure 7 - Program output.
<!doctype html public "-//w3c//dtd html 4.0 transitional//en"><html><head><meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"><meta name="GENERATOR" content="Mozilla/4.7 [en] (WinNT; I) [Netscape]"><title>Java and JavaScript Programming, by Richard G Baldwin</title></head><body bgcolor="#FFFFFF" link="#0000FF" vlink="#FF0000" lang="EN-US"><h1>Baldwin's Test Page 1</h1>Click<a href="http://www2.austin.cc.tx.us/baldwin/page2.html">here</a>to view page 2<p>Note: The material on this page is not intended to be of any particular value. This file is posted for the purpose of testing HTTP networkprograms only.<p>The following red bar is a centered gif file.<center><p><img SRC="red_thick_line_1.gif" BORDER=0 id="_x0000_i1025" height=9 width=300></center><center><h2>The following is a centered two-column table</h2></center>

The beginning of the program

The program begins in Listing 5 .

Listing 5 - Beginning of the program named Java4640d.
import java.net.*; import java.io.*;class Java4640d{ public static void main(String[]args){ String dataLine;try{ //Get a URL objectURL url = new URL( "http://www.austincc.edu/baldwin/page1.html");

As before, I will ignore the exception-handling code while discussing this program.

Create a URL object

As you saw in the previous program, the URL class has several different constructors, each of which can create a new URL object on the basis of URLinformation provided as parameters to the constructor. The constructors differ in terms of how the URL information is provided.

Questions & Answers

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?
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
how can I make nanorobot?
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.
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