Category: WebStandards

Enforcing and encouraging online standards such as XHTML, CSS, JavaScript.

Eclipse ResourceBundle Editor

I typically use the open-source Eclipse IDE for most of my Java and PHP work. For my corporate work, this means that I use IBM‘s packaged RAD and WSAD offerings that are based on various versions of the Eclipse framework.

When working on Internationalized (I18n) applications, most experienced Java architects rely on ResourceBundles to store the various text that is needed for different languages, problem is that editing these files becomes problematic, especially when dealing with multi-byte character sets as are often used in Unicode (non Latin-1, aka ISO-8859-1) languages.

The best editor I’ve found for this case is, as you may have guessed, free for download.

Here’s the links:

Cheers!

Resume and skills

I’d be doing myself a great dis-service if I didn’t take the opportunity to share my resume with readers of this blog. You’ve obviously found me because you have a similar interest to those of my own, perhaps you have need of part or full time knowledgeable employees with similar skills to my own.

I’m currently employed full-time and will not consider relocation or accept contract work, but would consider small side jobs in some situations.

Please see my online resume at:

http://www.skotfred.com/resume.php

Additionally, I generally have my information available on most job boards such as:

NOTE: Resume available in other formats (such as Word) by request.

Good Day!

Downloadable WebFonts

To maintain accessibility and SEO (Search Engine Optimization), there’s often a need to be creative with fonts. This is sometimes due to aesthetics, but often to meet technical needs like foreign non-Latin languages that have unique characters/glyphs not normally installed on workstations. Producing images for each character would be very time consuming, bandwidth intensive and destroy search engine rankings.

Create embedded fonts using one of 2 available formats:

1. Portable Font Resources (.pfr): TrueDoc technology was developed by Bitstream and licensed by Netscape. It can be viewed by Navigator 4.0+ and Explorer 4.0+ on Windows, Mac, and Unix platforms.

<link rel = “fontdef” src=”myfont.pfr” />

2. Embeddable Open Type (.eot): Compatible only with Explorer 4.0+ on the Windows platform. Create .eot files using Microsoft’s free Web Embedding Font Tool (WEFT).

<style type=”text/css”>
<–!
@font-face {
src:url(/fonts/myfont.eot);
}
–>
</style>

References:

Tooling:

Tutorials:

Cheers!

Browser Rendering Engines

This is knowledge that is generally “tribal” by nature, reserved to only the nerdiest web developers, recently I was asked to name these and failed. Here’s the bounty of my research.

Gecko is generally considered to be the second most-popular layout engine on the Web, after Trident (used by Internet Explorer for Windows since version 4), and followed by WebCore (used by Safari) and Presto (used by Opera).

Gecko is the open source, free software web browser layout engine used in all Mozilla-branded software and its derivatives, including later Netscape browser releases. Written in C++ and licensed under MPL/GPL/LGPL triple license, Gecko is designed to support open Internet standards. Originally created by Netscape Communications Corporation, its development is now overseen by the Mozilla Foundation.

Trident (also known as MSHTML) is the name of the layout engine for the Microsoft Windows version of Internet Explorer. It was first introduced with the release of Internet Explorer version 4 in October 1997, has been steadily upgraded and remains in use today. For version 7 of Internet Explorer, Microsoft made significant changes to the Trident layout engine to improve compliance with web standards and add support for new technologies. Despite these changes, Trident remains significantly less compliant than competing layout engines Gecko, Presto and WebCore.

Presto is the name of the current (Opera 9 series) layout engine for the Opera web browser developed by Opera Software. It was first released (following several public betas and technical previews) on January 28, 2003 in Opera 7.0 for Windows. Presto replaced the Elektra engine used in versions 4–6 of Opera. Presto differs from Elektra in that it is dynamic: the page or parts of it can be re-rendered in response to DOM and script events. The Presto layout engine is only available as a part of Opera browser or related products. The source or binary (DLL) forms of the engine are not publicly available. Subsequent releases have seen a number of bugs fixed and optimizations to improve the speed of the ECMAScript (“JavaScript“) engine.

Tasman is the name of the layout engine introduced with version 5 of Internet Explorer for Mac. Tasman was an attempt to improve support for web standards, as defined by the World Wide Web Consortium. At the time of its release, Tasman was seen as the layout engine with the best support for web standards such as HTML and CSS. Unfortunately, MSIE for Mac is no longer supported, but newer versions of Tasman are incorporated in some other current Microsoft products.

Cheers!

Preventing portions of a webpage from printing

A colleague asked me about my solution for this just the other day, here’s the quick solution.

  1. Add a CSS class attribute to the items.  Assuming they are <div>’s for header and footer, they would look like my example below, but you can add the ‘no-print’ class to anything you don’t want printed.
  2. Add a stylesheet with media=”print” to change the visibility and/or display attributes of that class.
  3. With a little more work, you could add a ‘no-screen’ solution too… this would be advantageous in cases where you may need to mask an account number or SSN.

<html>
<head>
<title>Example</title>
<link media=”print” href=”print.css” type=”text/css” rel=”stylesheet” />
</head>
<body>
<div class=”no-print”>This is your header</div>
<div>this is the body</div>
<div class=”no-print”>this is your footer</div>
</body>
</html>

print.css could then contain:

.no-print { display:none; }

Cheers!

MSIE PNG Alpha Transparency

In usual form, MSIE doesn’t directly implement Alpha-Transparency on PNG images. Typically this feature is used to allow for anti-aliased gradients on images so that they can be used to support a variety of backgrounds.

There are a variety of solutions online for this problem, however I take issue with most, here’s why:

  • .htc files – this is a proprietary Microsoft solution, to add support on most web servers the MIME type must also be added.
  • filter: progid: – this too is utilizing a standard in Microsoft’s own particular way.

While neither of these is perfect, the ‘filter:’ is obviously the best of two evils. Surround it with the “Conditional If” comments (previously documented) and you’re at least safe for most other browsers.

Here’s my example code:

<!–[if gte IE 5.5000]>
<script type=”text/javascript”>
function correctPNG() // correctly handle PNG transparency in Win IE 5.5 or higher.
{
for(var i=0; i<document.images.length; i++)
{
var img = document.images[i]
var imgName = img.src.toUpperCase()
if (imgName.substring(imgName.length-3, imgName.length) == “PNG”)
{
var imgID = (img.id) ? “id='” + img.id + “‘ ” : “”;
var imgClass = (img.className) ? “class='” + img.className + “‘ ” : “”;
var imgTitle = (img.title) ? “title='” + img.title + “‘ ” : “title='” + img.alt + “‘ “;
var imgStyle = “display:inline-block;” + img.style.cssText;
if (img.align == “left”) imgStyle = “float:left;” + imgStyle;
if (img.align == “right”) imgStyle = “float:right;” + imgStyle;
if (img.parentElement.href) imgStyle = “cursor:hand;” + imgStyle;
var strNewHTML = “<span ” + imgID + imgClass + imgTitle
+ ” style=\”” + “width:” + img.width + “px;height:” + img.height + “px;” + imgStyle + “;”
+ “filter:progid:DXImageTransform.Microsoft.AlphaImageLoader”
+ “(src=\'” + img.src + “\’, sizingMethod=’scale’);\”></span>”;
img.outerHTML = strNewHTML;
i = i-1;
}
}
}
window.attachEvent(“onload”, correctPNG);
</script>
<![endif]–>

References:

Good luck out there!

HTTP Forward vs. Redirect

A Controller servlet may perform either a forward or a redirect operation at the end of processing a request. It is important to understand the difference between these two cases, in particular with respect to browser reloads of web pages.

Forward

  • a forward is performed internally by the application (servlet).
  • the browser is completely unaware that it has taken place, so its original URL remains intact
  • any browser reload of the resulting page will simple repeat the original request, with the original URL

Redirect

  • a redirect is a two step process, where the web application instructs the browser to fetch a second URL, which differs from the original
  • a browser reload of the second URL will not repeat the original request, but will rather fetch the second URL
  • redirect is marginally slower than a forward, since it requires two browser requests, not one
  • objects placed in the original request scope are not available to the second request.

There are several ways to perform a Redirect, here are a few common ones:

  • URL Redirection (HTTP 301): 
    HTTP/1.1 301 moved permanently

Location: http://www.example.org/
  • HTTP Refresh Header (Not Recommended) 
    HTTP/1.1 200 ok

Refresh: 0; url=http://www.example.com/
  • HTML <meta /> tag 
    <meta http-equiv="refresh" content="0; URL=http://www.example.org/" />
  • JavaScript (many possible solutions, generally not accessible or searchable) 
    <script type="text/javascript">location.href='http://www.example.org/';</script>

In general, a forward should be used if the operation can be safely repeated upon a browser reload of the resulting web page; otherwise, redirect must be used. Typically, if the operation performs an edit on the datastore, then a redirect, not a forward, is required. This is simply to avoid the possibility of inadvertently duplicating an edit to the database.

More explicitly :

  • for SELECT operations, use a forward
  • for INSERT, UPDATE, or DELETE operations, use a redirect

In HTML, a <FORM> tag can either GET or POST its data. In this context, a GET corresponds to a SELECT-then-forward, and a POST corresponds to an edit-then-redirect.

It is strongly recommended that forms for the input of search criteria should use GET, while forms for editing database records should use POST.

SECURITY NOTE: When using GET, be sure to not expose sensitive data in the URL’s.

Single FORM INPUT causes submit on Enter/Return

This is a browser oddity that I’ve had to code around for years.  In most modern browsers (currently Mozilla Firefox 2.x and MSIE 7.0), when a FORM contains only one editable INPUT field pressing the Enter or Return key will automatically submit the form, but when there are more than one the form is not submitted.   This irregularity in the single field case is responsible for several odd errors, and often results in double-submits of form data to the server.

Here’s a newer solution to the problem, the ‘magic’ is in the javascript events that we’ve added to the FORM object itself, no longer do you have to place event handlers on every INPUT field as has often been done in the past.

NOTE: not completely valid XHTML for ease of documentation and readability.

<html>
<head>
<title>test of input submit</title>
<script type=”text/javascript”>
function keycheckForm(formObj,evt){
if(isEnter(evt)){
//alert(‘in form’);
if(checkFormInputs(formObj)){
formObj.submit();
}
}
}
/*
* Added to handle enter key press
* NOTE: this is based on  a ‘legacy’ function [checkEnter(e)] that returned the reverse boolean values.
* @param evt Event
* @return boolean
*/
function isEnter(evt){ //e is event object passed from function invocation
var characterCode; //literal character code will be stored in this variable
if(evt && evt.which){ //if which property of event object is supported (NN4)
characterCode = evt.which; //character code is contained in NN4’s which property
}else{
characterCode = evt.keyCode; //character code is contained in IE’s keyCode property
}
var rc = false;
if(characterCode == 13){ //if generated character code is equal to ascii 13 (if enter key)
rc = true;
}
return rc;
}
/**
* @param formObj Object
*/
function checkFormInputs(formObj){
var rc = false;
var allInputs=formObj.getElementsByTagName(‘INPUT’);
var formInputs = allInputs.length;
var textInputs=0;
if(formInputs>1){
var ct = allInputs.length;
var i;
for(i=0; i < ct; i++){
var inputObj = allInputs[i];
var typ = inputObj.type;
if ((typ==’text’) || (typ==’password’)) {
textInputs=textInputs+1;
}
}
if(textInputs>1){
rc=true;
}
}
if(rc==false){
//alert(“blocked because of size”);
}
return rc;
}
</script>
</head>
<body>
<form action=”example.php” method=”get” onkeypress=”return keycheckForm(this,event);” onsubmit=”return checkFormInputs(this);”>
<input type=”text” name=”textfield1″ value=”testing1″ />
<button type=”button” name=”mybutton” onclick=”this.form.submit();”>Click Me</button>
</form>
</body>
</html>

Cheers!

Version Control comments

When working on large, multi-group projects I’ve found that it often helps to have information about the ‘version’ of an asset written into the source file (HTML, JSP, PHP, CSS, JS, or other ‘text’ formats).

This is easily accomplished with most version control packages and is done automatically if the following are added inside of an appropriate comment section in the file. The below examples are Java based, but can be easily adopted to any file type.

This is especially helpful when reviewing JavaDoc, and crucial for deployed text files such as CSS and JS as it makes debugging them much easier.

These work with CVS, Subversion, Serena Changeman DS, MKS Source Integrity and a variety of other products.

Raw Source:

/*
$Id: $
$Author: $
$Revision: $
$Date: $

<pre>
$Log: $
</pre>
*/

At check-in becomes:

/*
$Id: project.readme 1.1 2007/07/30 10:42:39CDT Scott dev $
$Author: Scott $
$Revision: 1.1 $
$Date: 2007/07/30 10:42:39CDT $

<pre>
$Log: project.readme $
Revision 1.1 2007/07/30 10:42:39CDT Scott
Scott. test
</pre>
*/

Cheers!

Open Source Image Editing Software

I’m usually a considered by most to be just a “programmer”, but occasionally the need comes up for someone to edit or create an image for a project. I might not be a designer, but I still need similar tools to accomplish this, but can’t justify the cost of Adobe Photoshop & Illustrator.

Here are some great (if not better) alternatives that are FREE and available on a variety of operating systems, not just Windows and Apple Macintosh.

GIMP – is an acronym for GNU Image Manipulation Program. It is suitable for a variety of image manipulation tasks, including photo retouching, image composition, and image construction.

Currently Supports:

  • GIF, JPEG, PNG, XPM, TIFF, TGA, MPEG, PS, PDF, PCX, BMP and many others.

It has many capabilities. It can be used as a simple paint program, an expert quality photo retouching program, an online batch processing system, a mass production image renderer, an image format converter, etc.

Inkscape – is an open-source vector graphics editor similar to Adobe Illustrator, Corel Draw, Freehand, or Xara X. What sets it apart is it’s native use of Scalable Vector Graphics (SVG), an open XML-based W3C standard.

Currently supports:

  • opening only SVG and SVGZ (gzipped SVG) formats.
  • save as SVG, SVGZ, Postscript/EPS/EPSi, Adobe Illustrator (*.ai), LaTeX (*.tex), and POVRay (*.pov).
  • import most raster formats (JPG, PNG, GIF, etc.) as bitmap images, but it can only export PNG bitmaps.
  • With the help of extensions, Inkscape can open/save as PDF, EPS, AI, Dia, Sketch and some others.

Together this suite can tackle most work that previously required costly software that isn’t available on many Operating Systems.

Happy drawing!