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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

where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
Ali
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..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
hey
Giriraj
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
Bhagvanji
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
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
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
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
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
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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