Cfexchange and character encoding

Hi!
I'm developing an application using the new cfexchange-tags.
The app outputs a list of calendar events from an MS Exchange 2003
server. It works nicely, as long as the event subjects don't
contain any non-english characters. As soon as the subject contains
for example "umlaut"-characters like ä or ö, the output
is bogus.
Should I, for example, make an appointment in Outlook with
the subject "Kimi Raikkonen" (without umlauts), the subject, when
retrived with cfexchangecalendar, displays OK:
{ts '2008-01-19 10:00:00'} Kimi Raikkonen
Then, if I use the umlaut-characters in the name "Kimi
Räikkönen", the resulting page reads:
{ts '2008-01-19 12:00:00'}
=?iso-8859-1?Q?Kimi_R=E4ikk=F6nen?=
Ok, I thought, this is the good old ISO/UTF-problem, so I
changed my Outlook-settings to utf-8 and tried again (with ä
and ö), ther result was:
{ts '2008-01-19 14:00:00'}
=?UTF-8?B?S2ltaSBSw6Rpa2vDtm5lbg==?=
- I run the ColdFusion8-server on linux, with the Cumulative
Hot Fix 2 installed
- I've tried the ExchangeServerLanguage-attribute in the
cfexchangeconnection tag to no avail
(This is nothing new. Every distribusion since the first MX
has had some problems with other character sets than lower ASCII.)
I would be grateful for any help in this!

Hi,
if I use the cfexchangecalendar tag to retrieve calendar data with german umlauts I recive text phrases such as "=?iso-8859-1?B?dGVzdPbk?=".
If I using the cfexchangemail tag with the same Exchange connection, everything is perfect and now the German umlauts are displayed correctly!
(CF 9.0.1, Exchange 2007, SBS 2008, IIS7)
Thanks
Olaf

Similar Messages

Problems with Forms and character encoding

I'm having problems trying to read unicode data inputted into a Form on my JSP page.
I've used the meta tag <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/> to set the charset of the page to UTF-8. I've inputted some chinese characters inot my form and when I try to read the subsequent request parameter in my servlet using request.getParameter() the string returned is this
"来源" which is the escape sequence required by HTML to display these characters.
From what I've read on the subject this doesn't seem like the expected value. I've tried other ways of getting the correct string value such as setting the character encoding request.setCharacterEncoding("UTF-8") and then converting the bytes using this encoding value but it doesn't seem to work.
I could write a method to split up the string using the ; as a token and working out the correct unicode character but this doesn't seem like the right thing to do.
Any help on how to pass the correct information from the Form in the JSP page to the servlet would be greatly appreciated

I don't believe that is correct, but if it's returning HTML escapes instead of URL Encoded characters, then it's the browser doing it. This is my test page for playing with Chinese...
<%@ page language="java" contentType="text/html; charset=UTF-8" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html>
<head>
<title></title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
</head>
<body bgcolor="#ffffff" background="" text="#000000" link="#ff0000" vlink="#800000" alink="#ff00ff">
<%
request.setCharacterEncoding("UTF-8");
String str = "\u7528\u6237\u540d";
String name = request.getParameter("name");
%>
req enc: <%= request.getCharacterEncoding() %><br />
rsp enc: <%= response.getCharacterEncoding() %><br />
str: <%= str %><br />
name: <%= name %><br />
<form method="GET" action="_lang.jsp" encoding="UTF-8">
Name: <input type="text" name="name" value="" >
<input type="submit" name="submit" value="GET Submit" />
</form>
<form method="POST" action="_lang.jsp" encoding="UTF-8">
Name: <input type="text" name="name" value="" >
<input type="submit" name="submit" value="POST Submit" />
</form>
</body>
</html>

Locale and character encoding. What to do about these dreadful ÅÄÖ??

It's time for me to get it into my head how this works. Please, help me understand before I go nuts.
I'm from Sweden and we use a few of these weird characters like ÅÄÖ.
If I create a file called "övrigt.txt" in windows, then the file will turn up as "?vrigt.txt" on my Linux pc (At least in the console, sometimes it looks ok in other apps in X). The same is true if I create the file in Linux and copy it to Windows, it will look just as weird on the other side.
As I (probably) can't change the way windows works, my question is what I have to do to have these two systems play nicely with eachother?
This is the output from locale:
LANG=en_US.utf8
LC_CTYPE="en_US.utf8"
LC_NUMERIC="en_US.utf8"
LC_TIME="en_US.utf8"
LC_COLLATE=C
LC_MONETARY="en_US.utf8"
LC_MESSAGES="en_US.utf8"
LC_PAPER="en_US.utf8"
LC_NAME="en_US.utf8"
LC_ADDRESS="en_US.utf8"
LC_TELEPHONE="en_US.utf8"
LC_MEASUREMENT="en_US.utf8"
LC_IDENTIFICATION="en_US.utf8"
LC_ALL=
Is there anything here I should change? I have tried using ISO-8859-1 with no luck. Mind you that I want to have the system wide language set to english. The only thing I want to achieve is that "Ö" on widows should turn up as "Ö" i Linux as well, and vice versa.
Please save my hair from being torn off, I'm going bald here...

Hey, thanks for all the answers!
I share my files in a number of ways, but mainly trough a web application called Ajaxplorer (very nice btw...). The thing is that as soon as a windows user uploads anything with special chatacters in the file name my programs, xbmc, console etc, refuses to read them correctly. Other ways of sharing is through file copying with usb sticks, ssh etc. It's really not the way of sharing that is the problem I think, but rather the special characters being used sometimes.
I could probably convert the filenames with suggested applications but then I'll set the windows users in trouble when they want to download them again, won't I?
I realize that it's cp1252 that is the bad guy in this drama. Is there no way to set/use cp1252 as a character encoding in Linux? It's probably a bad idea as utf8 seems like the future way to go, but the fact that these two OS's can't communicate too well in this area is pretty useless if you ask me.
To wrap this up I'll answer some questions...
@EVRAMP: I'm actually using pcmanfm, but that is only for me and I'm not dealing very often with vfat partitions to be honest.
@pkervien: Well, I think I mentioned my forms of sharing above. (kul med lite arch-svenskar!)
@quarkup: locale.gen is edited and both sv.SE and en_US have utf-8 and ISO-8859 enabled and generated.
...and to clearify things even further. It doesn't matter if I get or provide a file via a usb stick, samba, ftp or by paper. All I want is for "Ö" to always be "Ö", everywhere.
I can't believe how hard this is to get around. Linus is finish for crying out loud. I thought he'd sorted this out the first thing he did. Maybe he doesn't deal with windows or their users at all

Character Encoding and File Encoding issue

Hi,
I have a file which has a data encoded using default locale.
I start jvm in same default locale and try to red the file.
I took 2 approaches :
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-- This apprach worked fine.
-- I also printed system property "file.encoding" which matched with current locales encoding (on unix cooand to get this is "locale charmap").
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-- The String contained garbled data, meaning encoding failed.
I tried printing encoding used by JVM using internal class, and "file.encoding" property as well.
These 2 values do not match, there is weird difference.
For e.g. for locale ja_JP.eucjp on linux box :
byte-character uses EUC_JP_LINUX encoding
file.encoding system property is EUC-JP-LINUX
To get byte to character encoding, I used following methods (sun.io.*):
ByteToCharConverter btc = ByteToCharConverter.getDefault();
System.out.println("BTC uses " + btc.getCharacterEncoding());
Do you have any idea why is it failing ?
My understanding was, file encoding and character encoding should always be same by default.
But, because of this behaviour, I am little perplexed.

But there's no character encoding set for this operation:baos.write("��".getBytes());

Character encoding again

Hi, i havent got any answer so i try to ask again...
I have created a page from Data Controls.
I have created parameter form. And table. Detail is showed at the bottom of page (there is shown current row through #bindings. . .
Everything works fine when i fill something into parameter form table is filtered by that criteria, when current row is changed, the detail is also changed. But when i fill some czech character into parametr form it works pretty bad.
The table is correctly filtered but when i make any other action after filtering, the table shows no rows.
I found what cause this problem. It is the Property in bindings that holds value for this parameter. When i first call bindings.findXXX.execute the Propertys value is "č" for example. That is correct and table shows filtered rows. After i perform another action (i think it is not dependent what the action is, but change current row fow example) the value in that Property has changed to "?" instead of "č" and because of this filter is applied again and table shows no rows. I have checked all encoding and character encoding is set to utf-8. Is this the problem and i miss some settings ?
1) menu tools-preferences-Environment
2) project properties- compiler-character encoding
3) in jspx
<?xml version='1.0' encoding='UTF-8'?>
<jsp:directive.page contentType="text/html;charset=UTF-8"
pageEncoding="UTF-8"/>
<afh:head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
</afh:head>
is there other ? i dont know i set this settings long ago ...
Please if someone know, give me some hint , thanks for help.
Jdeveloper 10.1.3.0.4(SU5)

check regional language settings on your machiner where u r application server is running. I faced this problem but was able to resolve by modifying the
NLS_LANG = AMERICAN_AMERICA.WE8ISO8859P1
NLS_LANG is under HKEY_LOCAL_MACHINE==>ORACLE
WE8ISO8859P1 is the standard encoding for my application developed in local indian language and works fine for me
THIS can help check out
Amit

Why differing Character Encoding and how to fix it?

I have PRS-950 and PRS-350 readers, both since 2011.
In the last year, I've been getting books with Character Encoding that is not easy to read. In playing around with my browsers and View -> Encoding menus, I have figured out that it has something to do with the character encoding within the epub files.
I buy books from several ebook stores and I borrow from the library.
The problem may be the entire book, but it is usually restricted to a few chapters, with rare occasion where the encoding changes within a chapter. Usually it is for a whole chapter, not part, and it can be seen in chapters not consecutive to each other.
It occurs whether the book is downloaded directly to my 950 reader or if I load it to either reader from my computer(s), which are all Mac OS X of several versions fom 10.4 to Mountain Lion. SInce it happens when the book is downloaded directly, I figure the operating system of my computer is not relevant.
There are several publishers involved, though Baen (no DRM ebooks) has not so far been one of them.
If I look at the books with viewers on the computer, the encoding is the same. I've read them in Calibre, in the Sony Reader App, and in Adobe Digital Editions 2.0. It's always the same.
I believe the encoding is inherent to the files. I would like to fix this if I can to make the books I've purchased, many of them in paper and electronically, more enjoyable to read on my readers.
Example: Iâ€™ve is printed instead of I've.
â€™ for apostrophe
â€œ the opening of a quotation,
â€? for closing the quotation,
and I think â€” is for a hyphen.
When a sentence had â€œâ€™m for " 'm at the beginning of a speech (when the character was slurring his words) it took me a while to figure out how it was supposed to read.
â€œâ€™Sides, â€™tis only for a moon. That ainâ€™t long.â€?
was in one recent book.
Translation: " 'Sides, 'tis only for a moon. That ain't long."
See what I mean?
Any ideas?

Hi
I wonder if it’s possible to download a free ebook with such issue, in order to make some “tests”.
Perhaps it’s possible, on free ebooks (without DRM), to add fonts by using softwares like Sigil.

Reading Advance Queuing with XMLType payload and JDBC Driver character encoding

Hi
I've got a problem retrieving the message from the queue with XMLType payload in Java.
It was working fine in 10g database but after the switch to 11g it returns corrupted string instead of real XML message. Database NLS_LANG setting is AL32UTF8
It is said that JDBC driver should deal with that automatically but it obviously don't in this case. When I dequeue the message using database functionality (DBMS_AQ package) it looks fine but not when using JDBC driver so Ithink it is character encoding issue or so. The message itself is enqueued by the database and supposed to be retrieved by dedicated EJB.
Driver file used: ojdbc6.jar
Additional libraries: aqapi.jar, xdb.jar
All file taken from 11g database installation.
What shoul dI do to get the xml message correctly?

Do you mean NLS_LANG is AL32UTF8 or the database character set is AL32UTF8? What is the database character set (SELECT value FROM nls_database_parameters WHERE parameter='NLS_CHARACTERSET')?
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Character Encoding for JSPs and HTML forms

After having read loads of postings on character encoding problems I'm still puzzled about the following problem:
I have an instance (A) of WL 8.1 SP3 on a WinXP machine and another instance (B) of WL 8.1 without any SP on a Win2K machine. The underlying Windows locale is english(US) in both cases.
The same application deployed as a war file to these instances does not behave in the same way when it comes to displaying non-Latin1-characters like the Euro symbol: Whereas (A) shows and accepts these characters as request-parameters, (B) does not.
Since the war file is the same (weblogic.xml, jsps and everything), the reason for this must either be the service-pack-level or some other configuration setting I overlooked.
Any hints are appreciated!

Try this:
Prefrences -> Content -> Fonts & Color -> Advanced
At the bottom, choose your Encoding.

Seeing � etc despite having View--Character encoding as unicode and auto-detect universal

On viewing some web pages see characters such as �, , (for example). But View-Character Encoding is set at Unicode (UTF-8) or Western (ISO8859-1) and Tools-Options-Content-Fonts-Advanced Encoding set with either of those

example of page:
http://scienceofdoom.com/2010/09/17/on-missing-the-point-by-chilingar-et-al-2008/
- a little over half way down, the section headed "Anthropogenic Imact on the Earth’s Climate – Tiny" from paragraph "And continue: " there are these non-characters in the equation (12) and subsequently.
Another page : http://www.zimbabwesituation.com/sep26_2010.html in the topic " Red warning lights" .
Most web-pages I read are without problem.
I contacted the writer of the first page and s/he had no idea why it happens.

Database Encoding and character set

Hi,
Is it possible to change [some easier straigtht forward way] the encodings and character set for a database [DB11 in this case]?
I have a database which has UTF16 and MSWIN1252 as the encoding and characterset, i want to change it to UTF8 for some testing and reasons.
Thanks,
Anupam

You should detail what you mean by encoding and character set.
A database has 2 character sets:
- the character set for CHAR, VARCHAR2 and CLOB
- the national character set for NCHAR, NVARCHAR2 and NCLOB.
You have 2 ways to change the database character set:
- with ALTER DATABASE statement
- with export/import
See http://download-uk.oracle.com/docs/cd/B10501_01/server.920/a96529/ch10.htm#1656

Web pages display OK, but print with garbage characters. I think it's character encoding, but don't know WHICH I should use. Have tried all Western and UTF options. Firefox 3.6.12

I used to only have troubles with headers & footers printing out as garbage characters. I tried changing Character Encoding, now entire pages have garbage characters, even though pages view ok when browsing.

If the pages look OK when you are browsing then it is not a problem with the encoding.<br />
It can be a problem with the font that is used and you can try to disable website fonts and posibly try a few different default fonts to see if that helps.
Tools > Options > Content : Fonts & Colors: Advanced (Allow pages to choose their own fonts, instead of my selections above)

Character encoding: Ansi, ascii, and mac, oh my!

I'm writing a program which has to search & replace data in user-supplied Rich Text documents (.rtf). Ideally, I would like to read the whole thing into a StringBuffer, so that I can use all of the functionality built into String and StringBuffer, and so that I can easily compare with constant Strings and chars.
The trouble that I have is with character encoding. According to the rtf spec, RTFs can be encoded in four different character encodings: "ansi", "mac", IBM PC code page 437, and IBM PC code page 850, none of which are supported by Java (see http://impulzus.sch.bme.hu/tom/szamitastechnika/file/rtfspec/rtfspec_6.htm#rtfspec_8 for the RTF spec and http://java.sun.com/j2se/1.3/docs/api/java/lang/package-summary.html#charenc for the character encodings supported by Java).
I believe, from a bit of googling, that they are all 8 bits/character, so I could read everything into a byte array and manipulate that directly. However, that would be rather nasty. I would have to be careful with the changes that I make to the document, so that I do not insert values that do not encode correctly in the document's character encoding. Overall, a large hassle.
So my question is - has anyone done something like this before? Any libraries that will make my job easier? Or am I missing something built into Java that will allow me to easily decode and reencode these documents?

DrClap, thanks for the response.
If I could map from the encodings listed above (which are given in the rtf doucment) to a java encoding name from the page that you listed, that would solve all my problems. However, there are a couple of problems:
a) According to this page - http://orwell.ru/info/diffs.htm - ANSI is a superset of ISO-8859-1. That page isn't exactly authoritative, but I can't afford to lose data.
b) I'm not sure what to do about the other character encodings. "mac" may correspond to "MacRoman" but that page lists a dozen or so other macintosh encodings. Gotta love crystal-clear MS documentation.

Character encoding and ByteOutputStream

Hi!
I'm currently working on a web application that needs to print non-english characters (e g swedish � � �). Currently this doesn't work, although i have set the character encoding for the HttpServletResponse.
I figure that it is this code that doesn't manage the non-english characters (it's not my own code but i need to fix it and, sorry to say, I'm not that experienced with streams):
ByteArrayOutputStream baos = new ByteArrayOutputStream(16384);
baos.write("��".getBytes());
resp.setDateHeader("Expires", 0);
resp.setContentLength(baos.size());
ServletOutputStream out = resp.getOutputStream();
out.write(baos.toByteArray());
out.flush();
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Cheers,
David

But there's no character encoding set for this operation:baos.write("��".getBytes());

How I set character encoding for everypage and alway?

I use Thai window 874 open the page when I select some website it contain Thai then click open new tab it change to western windows 1252. It can not display Thai. I must set character encoding to Thai windows 874 everytime.

Try this:
Prefrences -> Content -> Fonts & Color -> Advanced
At the bottom, choose your Encoding.

What every developer should know about character encoding

This was originally posted (with better formatting) at Moderator edit: link removed/what-every-developer-should-know-about-character-encoding.html. I'm posting because lots of people trip over this.
If you write code that touches a text file, you probably need this.
Lets start off with two key items
1.Unicode does not solve this issue for us (yet).
2.Every text file is encoded. There is no such thing as an unencoded file or a "general" encoding.
And lets add a codacil to this – most Americans can get by without having to take this in to account – most of the time. Because the characters for the first 127 bytes in the vast majority of encoding schemes map to the same set of characters (more accurately called glyphs). And because we only use A-Z without any other characters, accents, etc. – we're good to go. But the second you use those same assumptions in an HTML or XML file that has characters outside the first 127 – then the trouble starts.
The computer industry started with diskspace and memory at a premium. Anyone who suggested using 2 bytes for each character instead of one would have been laughed at. In fact we're lucky that the byte worked best as 8 bits or we might have had fewer than 256 bits for each character. There of course were numerous charactersets (or codepages) developed early on. But we ended up with most everyone using a standard set of codepages where the first 127 bytes were identical on all and the second were unique to each set. There were sets for America/Western Europe, Central Europe, Russia, etc.
And then for Asia, because 256 characters were not enough, some of the range 128 – 255 had what was called DBCS (double byte character sets). For each value of a first byte (in these higher ranges), the second byte then identified one of 256 characters. This gave a total of 128 * 256 additional characters. It was a hack, but it kept memory use to a minimum. Chinese, Japanese, and Korean each have their own DBCS codepage.
And for awhile this worked well. Operating systems, applications, etc. mostly were set to use a specified code page. But then the internet came along. A website in America using an XML file from Greece to display data to a user browsing in Russia, where each is entering data based on their country – that broke the paradigm.
Fast forward to today. The two file formats where we can explain this the best, and where everyone trips over it, is HTML and XML. Every HTML and XML file can optionally have the character encoding set in it's header metadata. If it's not set, then most programs assume it is UTF-8, but that is not a standard and not universally followed. If the encoding is not specified and the program reading the file guess wrong – the file will be misread.
Point 1 – Never treat specifying the encoding as optional when writing a file. Always write it to the file. Always. Even if you are willing to swear that the file will never have characters out of the range 1 – 127.
Now lets' look at UTF-8 because as the standard and the way it works, it gets people into a lot of trouble. UTF-8 was popular for two reasons. First it matched the standard codepages for the first 127 characters and so most existing HTML and XML would match it. Second, it was designed to use as few bytes as possible which mattered a lot back when it was designed and many people were still using dial-up modems.
UTF-8 borrowed from the DBCS designs from the Asian codepages. The first 128 bytes are all single byte representations of characters. Then for the next most common set, it uses a block in the second 128 bytes to be a double byte sequence giving us more characters. But wait, there's more. For the less common there's a first byte which leads to a sersies of second bytes. Those then each lead to a third byte and those three bytes define the character. This goes up to 6 byte sequences. Using the MBCS (multi-byte character set) you can write the equivilent of every unicode character. And assuming what you are writing is not a list of seldom used Chinese characters, do it in fewer bytes.
But here is what everyone trips over – they have an HTML or XML file, it works fine, and they open it up in a text editor. They then add a character that in their text editor, using the codepage for their region, insert a character like ß and save the file. Of course it must be correct – their text editor shows it correctly. But feed it to any program that reads according to the encoding and that is now the first character fo a 2 byte sequence. You either get a different character or if the second byte is not a legal value for that first byte – an error.
Point 2 – Always create HTML and XML in a program that writes it out correctly using the encode. If you must create with a text editor, then view the final file in a browser.
Now, what about when the code you are writing will read or write a file? We are not talking binary/data files where you write it out in your own format, but files that are considered text files. Java, .NET, etc all have character encoders. The purpose of these encoders is to translate between a sequence of bytes (the file) and the characters they represent. Lets take what is actually a very difficlut example – your source code, be it C#, Java, etc. These are still by and large "plain old text files" with no encoding hints. So how do programs handle them? Many assume they use the local code page. Many others assume that all characters will be in the range 0 – 127 and will choke on anything else.
Here's a key point about these text files – every program is still using an encoding. It may not be setting it in code, but by definition an encoding is being used.
Point 3 – Always set the encoding when you read and write text files. Not just for HTML & XML, but even for files like source code. It's fine if you set it to use the default codepage, but set the encoding.
Point 4 – Use the most complete encoder possible. You can write your own XML as a text file encoded for UTF-8. But if you write it using an XML encoder, then it will include the encoding in the meta data and you can't get it wrong. (it also adds the endian preamble to the file.)
Ok, you're reading & writing files correctly but what about inside your code. What there? This is where it's easy – unicode. That's what those encoders created in the Java & .NET runtime are designed to do. You read in and get unicode. You write unicode and get an encoded file. That's why the char type is 16 bits and is a unique core type that is for characters. This you probably have right because languages today don't give you much choice in the matter.
Point 5 – (For developers on languages that have been around awhile) – Always use unicode internally. In C++ this is called wide chars (or something similar). Don't get clever to save a couple of bytes, memory is cheap and you have more important things to do.
Wrapping it up
I think there are two key items to keep in mind here. First, make sure you are taking the encoding in to account on text files. Second, this is actually all very easy and straightforward. People rarely screw up how to use an encoding, it's when they ignore the issue that they get in to trouble.
Edited by: Darryl Burke -- link removed

DavidThi808 wrote:
This was originally posted (with better formatting) at Moderator edit: link removed/what-every-developer-should-know-about-character-encoding.html. I'm posting because lots of people trip over this.
If you write code that touches a text file, you probably need this.
Lets start off with two key items
1.Unicode does not solve this issue for us (yet).
2.Every text file is encoded. There is no such thing as an unencoded file or a "general" encoding.
And lets add a codacil to this – most Americans can get by without having to take this in to account – most of the time. Because the characters for the first 127 bytes in the vast majority of encoding schemes map to the same set of characters (more accurately called glyphs). And because we only use A-Z without any other characters, accents, etc. – we're good to go. But the second you use those same assumptions in an HTML or XML file that has characters outside the first 127 – then the trouble starts. Pretty sure most Americans do not use character sets that only have a range of 0-127. I don't think I have every used a desktop OS that did. I might have used some big iron boxes before that but at that time I wasn't even aware that character sets existed.
They might only use that range but that is a different issue, especially since that range is exactly the same as the UTF8 character set anyways.
>
The computer industry started with diskspace and memory at a premium. Anyone who suggested using 2 bytes for each character instead of one would have been laughed at. In fact we're lucky that the byte worked best as 8 bits or we might have had fewer than 256 bits for each character. There of course were numerous charactersets (or codepages) developed early on. But we ended up with most everyone using a standard set of codepages where the first 127 bytes were identical on all and the second were unique to each set. There were sets for America/Western Europe, Central Europe, Russia, etc.
And then for Asia, because 256 characters were not enough, some of the range 128 – 255 had what was called DBCS (double byte character sets). For each value of a first byte (in these higher ranges), the second byte then identified one of 256 characters. This gave a total of 128 * 256 additional characters. It was a hack, but it kept memory use to a minimum. Chinese, Japanese, and Korean each have their own DBCS codepage.
And for awhile this worked well. Operating systems, applications, etc. mostly were set to use a specified code page. But then the internet came along. A website in America using an XML file from Greece to display data to a user browsing in Russia, where each is entering data based on their country – that broke the paradigm.
The above is only true for small volume sets. If I am targeting a processing rate of 2000 txns/sec with a requirement to hold data active for seven years then a column with a size of 8 bytes is significantly different than one with 16 bytes.
Fast forward to today. The two file formats where we can explain this the best, and where everyone trips over it, is HTML and XML. Every HTML and XML file can optionally have the character encoding set in it's header metadata. If it's not set, then most programs assume it is UTF-8, but that is not a standard and not universally followed. If the encoding is not specified and the program reading the file guess wrong – the file will be misread.
The above is out of place. It would be best to address this as part of Point 1.
Point 1 – Never treat specifying the encoding as optional when writing a file. Always write it to the file. Always. Even if you are willing to swear that the file will never have characters out of the range 1 – 127.
Now lets' look at UTF-8 because as the standard and the way it works, it gets people into a lot of trouble. UTF-8 was popular for two reasons. First it matched the standard codepages for the first 127 characters and so most existing HTML and XML would match it. Second, it was designed to use as few bytes as possible which mattered a lot back when it was designed and many people were still using dial-up modems.
UTF-8 borrowed from the DBCS designs from the Asian codepages. The first 128 bytes are all single byte representations of characters. Then for the next most common set, it uses a block in the second 128 bytes to be a double byte sequence giving us more characters. But wait, there's more. For the less common there's a first byte which leads to a sersies of second bytes. Those then each lead to a third byte and those three bytes define the character. This goes up to 6 byte sequences. Using the MBCS (multi-byte character set) you can write the equivilent of every unicode character. And assuming what you are writing is not a list of seldom used Chinese characters, do it in fewer bytes.
The first part of that paragraph is odd. The first 128 characters of unicode, all unicode, is based on ASCII. The representational format of UTF8 is required to implement unicode, thus it must represent those characters. It uses the idiom supported by variable width encodings to do that.
But here is what everyone trips over – they have an HTML or XML file, it works fine, and they open it up in a text editor. They then add a character that in their text editor, using the codepage for their region, insert a character like ß and save the file. Of course it must be correct – their text editor shows it correctly. But feed it to any program that reads according to the encoding and that is now the first character fo a 2 byte sequence. You either get a different character or if the second byte is not a legal value for that first byte – an error.
Not sure what you are saying here. If a file is supposed to be in one encoding and you insert invalid characters into it then it invalid. End of story. It has nothing to do with html/xml.
Point 2 – Always create HTML and XML in a program that writes it out correctly using the encode. If you must create with a text editor, then view the final file in a browser.
The browser still needs to support the encoding.
Now, what about when the code you are writing will read or write a file? We are not talking binary/data files where you write it out in your own format, but files that are considered text files. Java, .NET, etc all have character encoders. The purpose of these encoders is to translate between a sequence of bytes (the file) and the characters they represent. Lets take what is actually a very difficlut example – your source code, be it C#, Java, etc. These are still by and large "plain old text files" with no encoding hints. So how do programs handle them? Many assume they use the local code page. Many others assume that all characters will be in the range 0 – 127 and will choke on anything else.
I know java files have a default encoding - the specification defines it. And I am certain C# does as well.
Point 3 – Always set the encoding when you read and write text files. Not just for HTML & XML, but even for files like source code. It's fine if you set it to use the default codepage, but set the encoding.
It is important to define it. Whether you set it is another matter.
Point 4 – Use the most complete encoder possible. You can write your own XML as a text file encoded for UTF-8. But if you write it using an XML encoder, then it will include the encoding in the meta data and you can't get it wrong. (it also adds the endian preamble to the file.)
Ok, you're reading & writing files correctly but what about inside your code. What there? This is where it's easy – unicode. That's what those encoders created in the Java & .NET runtime are designed to do. You read in and get unicode. You write unicode and get an encoded file. That's why the char type is 16 bits and is a unique core type that is for characters. This you probably have right because languages today don't give you much choice in the matter.
Unicode character escapes are replaced prior to actual code compilation. Thus it is possible to create strings in java with escaped unicode characters which will fail to compile.
Point 5 – (For developers on languages that have been around awhile) – Always use unicode internally. In C++ this is called wide chars (or something similar). Don't get clever to save a couple of bytes, memory is cheap and you have more important things to do.
No. A developer should understand the problem domain represented by the requirements and the business and create solutions that appropriate to that. Thus there is absolutely no point for someone that is creating an inventory system for a stand alone store to craft a solution that supports multiple languages.
And another example is with high volume systems moving/storing bytes is relevant. As such one must carefully consider each text element as to whether it is customer consumable or internally consumable. Saving bytes in such cases will impact the total load of the system. In such systems incremental savings impact operating costs and marketing advantage with speed.

Cfexchange and character encoding

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