this <div id="adiv"></div> will in JSPX somehow be translated into <div id="adiv" />. The way I got it to work is to add empty comments inside like <div id="adiv"><!-- --></div>. I dont understand why this is happening and is there a better to solve this issue?
That's by JSP specification:
JSP.6.2.3 Semantic Model
...
To clearly explain the processing of whitespace, we follow the structure of the
XSLT specification. The first step in processing a JSP document is to identify the
nodes of the document. Then, all textual nodes that have only white space are
dropped from the document; the only exception are nodes in a jsp:text element,
which are kept verbatim. The resulting nodes are interpreted as described in the
following sections. Template data is either passed directly to the response or it is
mediated through (standard or custom) actions.
In theory, it should not harm if you use a XHTML doctype to present the document in the client side instead of a HTML doctype. However, even the XHTML spec requires some elements to be not self-closing. Another workaround would be using <jsp:text /> instead of a comment.
<div id="adiv"><jsp:text /></div>
JSP(X) is however an old view technology. Its successor, Facelets, does a better job in this.
See also:
JSP Document/JSPX: what determines how tabs/space/linebreaks are removed in the output?
Why don't self-closing script tags work?
Related
I would like to know what kind of text belongs to the HTML <code> element and what does not?
For example, I know that this is a good usage of HTML <code> tag:
Use the <code>str()</code> function to convert the object into a string.
But I am not sure if these are good usages of the <code> tag:
1. The list of users can be found at <code>/etc/passwd</code>.
2. We need to wait for <code>200 OK</code> response before the next step.
3. Enter the <code>ls</code> command to obtain a directory listing.
4. Compile the source code in <code>foo.c</code> to <code>foo.o</code>.
Is there a standards-document or a W3C guideline document or a similarly authoritative reference that precisely defines what elements may belong to the HTML <code> element and what may not?
The definition of the code element (from HTML 5.2) is:
The code element represents a fragment of computer code. This could be an XML element name, a file name, a computer program, or any other string that a computer would recognize.
This is what decides whether it’s allowed (i.e., semantic) to use the element or not. But you should also check if there is a more specific element available.
Reviewing your examples
Use the <code>str()</code> function to convert the object into a string.
This is fine.
The list of users can be found at <code>/etc/passwd</code>.
This is fine.
We need to wait for <code>200 OK</code> response before the next step.
You could consider using the samp element instead, which represents "sample or quoted output from another program or computing system".
Enter the <code>ls</code> command to obtain a directory listing.
You could consider using the kbd element instead, which represents "user input (typically keyboard input, […])".
Compile the source code in <code>foo.c</code> to <code>foo.o</code>.
This is fine.
There are no good or bad usages of <code> tag.
To be more precise, HTML spec (and browsers, for that matter) is not opinionated on the syntax of a <code> tag's content. It does not check if it's valid code in any existing programming language.
Any phrasing content is valid from HTML spec's point of view.
Any non-phrasing content is invalid.
The code tag is similar to <pre> tag and allows browsers (through their default stylesheets) and users to style content differently, based on the fact it is a different tag.
Many times, when code snippets, functions or method names (specific to programming) are used in other content, it is important (or at least desired) they are marked (and formatted) differently than normal text.
That is the intended purpose for which <code> tag was added to HTML.
This does not mean there's any mechanism in place stopping you from using it for any other purpose you may see fit, as long as it is fit for that purpose, given its limitation at only containing phrasing content.
This would be my first website and I do not want to leave it these errors. Can someone please help me with these ones?
Error 1:
if (xmlhttp.readyState==4 && xmlhttp.status==200)
error: character "&" is the first character of a delimiter but occurred as data.
WHEN i &, then my AJAX code stops working
I have no clue how to correct this one.
Error 2:
…ems"><a href="brushdescription.php?id=<?php echo $popularbrushesrow['bd_brushi…
error: character "<" is the first character of a delimiter but occurred as data
Again the same error but for < this time
UPDATE:
I am using this doctype:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
< and & are some of the predefined entities in XML, which need escaping when validating the page as XML or XHTML.
< should be replaced with < (less than)
& should be replaced with & (ampersand)
However, if using these characters in JavaScript you can (instead) enclose the script in a <![CDATA[]]> section, which instructs the parser to not interpret the code as markup and will also not result in a validation error.
Try wrapping your Javascript with <![CDATA[]]> tags like so:
<script>
//<![CDATA[
// Javascript goes here.
//]]>
</script>
Also, you should look into separation of concerns. Try to move your logic out of you view. If your Javascript is in your HTML page, try to include it from a separate file.
From Wikipedia:
HyperText Markup Language (HTML), Cascading Style Sheets (CSS), and JavaScript (JS) are complementary languages used in the development of webpages and websites. HTML is mainly used for organization of webpage content, CSS is used for definition of content presentation style, and JS defines how the content interacts and behaves with the user. Historically, this was not the case though. Prior to the introduction of CSS, HTML performed both duties of defining semantics and style.
Use HTML, not XHTML (or, if you insist on using XHTML, see the guidelines on how to write XHTML that can be parsed as HTML).
I can't see how you could have generated that error. Some more context would be useful.
For the first error, consider switching from XHTML to HTML5. There's really little reason to use XHTML. Use this:
<!DOCTYPE html>
The W3C validator is for client-side code, but it seems you are trying to validate server-side code, hence the PHP tag. Send the rendered code for validation and the second error will go away. The rendered code is the one visible in the browser under "View source". You can supply the URL if it's already online somewhere.
By XML rules, “The ampersand character (&) and the left angle bracket (<) MUST NOT appear in their literal form, except when used as markup delimiters, or within a comment, a processing instruction, or a CDATA section. If they are needed elsewhere, they MUST be escaped using either numeric character references or the strings " & " and " < " respectively.” So “&&” is to be written as &&.
However, this is such works only when the document is processed as “real XHTML” due to having been sent with an XML content type, e.g. with the HTTP header Content-Type: application/xhtml+xml. Doing so implies that old versions of IE will choke on it and modern browsers will refuse to render the document at all if it contains any well-formedness error. People don’t normally do that – they just use XHTML because someone told them to do so, and their documents are sent with an HTML document type, which means among other things that script element content is processed differently. This explains why a fix that satisfies the validator makes the page break.
In the XHTML 1.0 specification, the (in)famous appendix C says: “Use external scripts if your script uses < or & or ]]> or --.” This is the simple cure if you need to use XHTML. Just put your script in an external file and “call” it with <script src="foo.js"></script>.
I'm working on a project where we went from XHTML to HTML back to XHTML and there are some definite behavioral changes going back with regards to the page rendering before the CSS loads and scripts that read styles reading them before the CSS loads. Can anyone shed some light on why the following is happening and what can be done about it?
Basically, I have a page with the following structure:
<body>
<!-- Content from Source A -->
<link href="http://a.example.com/style.css" />
<header>...</header>
<!-- Content from Source B -->
<link href="http://b.example.com/style.css" />
<div>...</div>
<!-- Content from Source A -->
<footer>...</footer>
<script src="http://a.example.com/script.js">
/* e.g. */
alert($('header').offset().height);
</script>
</body>
When we were in HTML rendering mode, the page blocks rendering at expected points. When we hit the Source A CSS, rendering pauses (blank screen); when we hit the Source B CSS, rendering pauses (header is visible). When we hit the Source A JavaScript, rendering pauses (full page shown) and the script reads element styles from their rendered state. (In reality, of course, WebKit doesn't stop parsing the DOM or executing JavaScript while the CSS loads, but it does halt execution at the first point where the script needs to read a style.)
When we are in XHTML mode, the page doesn't halt rendering at all and will render the entire page completely unstyled. After that, it appears to process the scripts and stylesheets in the order loaded, or rather it executes the scripts in order but doesn't wait for the stylesheet to load before executing a loaded script. This means that the page will render three times (unformatted, with one stylesheet, and with two stylesheets) and the script may infer completely inaccurate values for element sizes.
Can someone shed light on this? This is happening in all WebKit browsers I've tested, including Chrome 17, Mobile Safari 5, and Android Browser 2.1. Is there any way to ensure HTML render ordering without resorting to the text/html mime type?
WebKit uses libxml2 to handle XML, which sends the parsed XHTML back to WebCore and JavaScriptCore to do the CSS rendering and JavaScript execution.
Stylesheet and script tags link to what's called an external entity in XML terminology. That means they are processed last. The XML spec says:
Except when standalone="yes", they must not process entity declarations or attribute-list declarations encountered after a reference to a parameter entity that is not read, since the entity may have contained overriding declarations; when standalone="yes", processors must process these declarations.
Since standalone="yes" specifies that the XML document should be validated by a DTD, this triggers a different processing model.
Link tags are handled differently than xml-stylesheet processing-instructions. The XML stylesheet spec says:
Any links to style sheets that are specified externally to the document (e.g. Link headers in some versions of HTTP [RFC2068]) are considered to create associations that occur before the associations specified by the xml-stylesheet processing instructions. The application is responsible for taking all associations and determining how, if at all, their order affects its processing.
Try commenting out the script tags and converting the link tags xml-stylesheet instructions. Also, try adding standalone="yes" to the XML declaration:
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<?xml-stylesheet href="foo.css"?>
In addition, the use of special characters, entities, and XSLT can further complicate the picture, since the processing model differs between HTML and an XML dialect like XHTML:
The range of allowed chars in XML is defined by the XML spec, and
the range is fully checked by libxml2. Not a concern, unless you parse
this for example with an HTML parser and give the preparsed tree to
libxml2 to serialize back. I hope you're not doing this as XSLT is
an XML language and must be parsed by an XML parser.
References
libxml2 Paser Internals
blink-dev => Intent to Deprecate and Remove: XSLT
blink-dev => Security: libxml2 growBuffer integer overflow on 64-bit machines
blink-dev => Stack-buffer-overflow in xmlSerializeHexCharRef
Webkit Title Index
I am generating WSDL/XSD for SOAP services from a UML model using IBM Rational Software Architect (RSA). RSA allows you to document the classes and attributes in the model using rich-formatting.
For example, I have the following documentation on a Trailer class:
A wheeled Vehicle that is designed for towing by another
Vehicle. Known subtypes include:
Caravan
BoxTrailer
BoatTrailer
When the UML model is transformed to WSDL/XSD (using the out-of-the-box UML to WSDL transform), the formatting is preserved as HTML markup inside the xsd:documentation element:
<xsd:complexType name="Trailer">
<xsd:annotation>
<xsd:documentation><p>
A wheeled <strong>Vehicle</strong> that is designed for towing by another <strong>Vehicle.</strong> Known
subtypes include:
</p>
<ul>
<li>
<strong>Caravan</strong>
</li>
<li>
<strong>BoxTrailer</strong>
</li>
<li>
<strong>BoatTrailer</strong>
</li>
</ul></xsd:documentation>
</xsd:annotation>
</xsd:complexType>
Unfortunately, this is really hard to read and I've been searching (with no luck) for a program that can view WSDL/XSD with documentation in HTML markup.
XmlSpy 2008 can't do it, RSA can't do it (which is a bit surprising, as it generated the XSD in the first place), neither can any web browser I've tried.
I did write a JET template that extracted the documentation from the model and outputted to HTML, and I could probably write some XSLT to do something similar from the XSD, but I was hoping there's a program out there (ideally free) that could view the documentation as HTML.
Essentially, I'd like to be able to tell the consumers of our web service that they can view the WSDL in X program if they want to read the documentation - does anybody know the best solution to this?
Edit:
Thanks for the suggestions, but I think I have a solution! I didn't realise that RSA can export a WSDL to HTML (right-click on WSDL, export, HTML). The generated HTML has a graphical view of each schema element, the documentation for each element, as well as the original source, and everything is hyperlinked together.
Most importantly, the documentation is richly-formatted again! One small caveat is that the ;nbsp's appear in the HTML output. This seems to be because the ampersand is escaped in the HTML:
Instead it should be
I will update my model-to-model transform to ensure that the ;nbsp's are replaced with real spaces (I don't believe I'll need non-breaking spaces in the documentation), so the generated WSDL/XSD won't ever have them.
I highly doubt if the standard xml/xsd editors can interpret the html tags and generate appropriate documentation. Oxygen XML Editor does a decent job of understanding and converting the XML entities (liket < etc) but HTML tags and entities are left as is. Below is the screen shot in design view.
The type of <xs:documentation> is <xs:any> so you should actually be able to include your documentation without escaping the markup, provided that it is a well formed XHTML fragment instead of HTML. I guess some XML Schema tools would be capable to interpret the embedded XHTML and show it as formatted text.
Do note that if the markup is not escaped it absolutely must be a well formatted XML fragment or the documentation element will cause your schema to be malformed. This applies also to HTML entities! If the documentation contains an (unescaped) entity reference (other than the 5 pre-defined XML entities), then your schema either must contain an external DTD reference or have an embedded DTD that defines what is the replacement text of that entity. In your case the documentation contains an entity reference. Probably easiest will be to replace such entities with the corresponding Unicode character/text or with character references (use for )
If you have a chance, try to include the documentation without escaping the markup and make sure that it will be well formed. Otherwise you probably need to process the documentation twice: 1) parse the schema and extract documentation 2) parse the documentation text again (possibly as HTML, not XML).
I've tried this with the latest build of QTAssistant and it shows like this in the Schema Help Panel only; I've put a feature request for the grid view, as well as the documentation generator to work the same. Is this what you're expecting?
The help panel shows the annotation of the schema object that is selected in the Graph/Diagram view. To display the help panel press F1.
This issue is fixed in RSA 8.0.4 - which now supports exporting to WSDL/XSD with plain text (as well as an option to sort the schema by type, then name alphabetically!).
To view the the documentation in a WSDL/XSD generated from a UML model in prior versions of RSA, the easiest solution is to export the WSDL/XSD as HTML using RSA. You can do this by right-clicking on the WSDL/XSD, selecting export, then selecting HTML.
The generated HTML has a graphical view of each schema element, the documentation for each element, as well as the original source, and everything is hyperlinked together.
Most importantly, the documentation (that's virtually unreadable in the WSDL/XSD) is richly-formatted again! One small caveat is that the ;nbsp's that RSA's documentation editor inserts also appear in the HTML output. This seems to be because the ampersand is not only escaped in the WSDL/XSD (which is good), but also in the HTML (bad!):
Instead it should be
A simple workaround to this is to replace all 's in the WSDL/XSD with real spaces before generating the HTML.
My website is XHTML 1.1, and I had added 'rel' attributes to the <li> and <div> tags on my page, to store data for a jQuery script on the page. When validating my page, I get the error: "there is no attribute 'rel'". So, what is the best way to store arbitrary data in HTML tags?
I am working on a comments page for my website. When a comment is entered, it is POSTed via AJAX, which returns JSON of all comments. I then look at the 'rel' values to see which comments are already on the page, and only add the new ones.
The jQuery code works fine, it's just the 'rel' attributes don't validate.
While it's not XHTML spec, you could use the data-* attributes that are included in HTML5's spec.
http://html5doctor.com/html5-custom-data-attributes/
If you want to remain fully XHTML 1.1 compliant, you'll need to create a schema and include its namespace in the html element, where the schema defines the attributes you want to use, and the elements to which they apply.
Extending XHTML
Since rel isn't valid attribute for li, you should use id instead attribute instead and it is valid there too.
I think it goes against the spirit of XHTML to store "arbitrary" data in tags. You should use the jQuery.data method instead.
JQuery seems to like classes as a way to store state for different html elements.
One example would be how jQuery UI Tabs use the ui-state-active class to define which tab is currently selected.
One benefit of this method is how easy you can select elements by the different states you are looking for.
As a reminder, you can add (virtually) as many classes to an element as you want and just separate them by spaces.
<li class="client_data already_added red_text etc">Bob</li>