JSR-315 ch.14 - web-fragment

[Roy Pozarelli]

In studying for SCWCD/OCPJWCD for J2EE 6, I've run across the issue that the subject spec does NOT list <web-fragment> and all of its elements like it does for <web-abb> (Figures/text). Is this anywhere? I've sort of derived it from ch.8, but was looking for something more definitive. Aside, in reading the diagrams, I'm a bit unsure of some of the symbolism used. Is there a spec out there that explains the symbolism in detail? I get the obvious stuff just not every detail.

[Ashok Kurakula]

Roy Pozarelli wrote:I've run across the issue that the subject spec does NOT list <web-fragment> and all of its elements like it does for <web-abb> (Figures/text). Is this anywhere?

I don't think that there are figures for web-fragment in the specs. But the specs clearly indicate that a web fragment is a part or all of the web.xml, meaning that it can include almost all the same elements that the web.xml uses. I think the only differences between the two are:

The root element for web fragments is <web-fragment>, while for the web.xml it is <web-app>

The web fragment descriptor file MUST be called web-fragment.xml, while the main app's deployment descriptor is called web.xml

For ordering purposes, web.xml contains <absolute-ordering> element while a web-fragment.xml contains an <ordering> element. Accordingly the sub elements also change.

[Piotr Nowicki]

Also remember that metadata-complete attribute of <web> element works different than <web-fragment> one.

You can take a look at the exact elements and their values here: http://java.sun.com/xml/ns/javaee/

There is a common part and a parts specific for web.xml only and for web-fragment.xml only.

HTH,

Cheers!

[Roy Pozarelli]

Thanks Pedro, do you have any links to the reading the symbolism issue?

[Piotr Nowicki]

Roy, sorry but I didn't understand your question... You mean links to the XML structure definition or a summary of web.xml vs web-fragment.xml or to the XML element types used in the link I provided?

If you don't know what particular element do, check it's type, i.e. on http://java.sun.com/xml/ns/javaee/web-common_3_0.xsd:
... <xsd:element name="mime-mapping" type="javaee:mime-mappingType"/> ...

So, the mime-mapping element type is "mime-mappingType". If you search for this in the same page you'll get:

<xsd:complexType name="mime-mappingType"> <xsd:annotation> <xsd:documentation> The mime-mappingType defines a mapping between an extension and a mime type. Used in: web-app </xsd:documentation> </xsd:annotation> ... </xsd:complexType>

And so on. All element types are quite explanatory. I know it's hard to read, but it's the most accurate source of knowledge - this is the XML Schema that every Servlets 3.0 web.xml and web-fragment.xml must conform to.

Does it answer your question?

Cheers!

[Roy Pozarelli]

In reading the actual JSR-315 Java Servlet Specification (Dec. 2009), in chapter 14 Deployment Descriptor, for ex. Figure 14-1 web-app Element Structure. They have symbols used to display the elements of <web-app> and they use various sybols for the elements, as well as within them. What I'm looking for is a link/document that defines those symbols that are used. I understand the obvious ones like 0..infinite, but I'm not sure of some others.

[Piotr Nowicki]

I really don't know what some of those symbols mean... I admit that I read about the obligatory/optional and multiplicity of elements from SCWCD Study Companion book and from the XML Schema.