Schematron

Schematron abstract patterns allow you to express such general ideas independently of the precise syntax used for the purchase order format.

ISO Schematron (Schematron) : Learn about this language for making assertions about the presence or absence of patterns in XML documents.

This code defines a Schematron abstract pattern that covers the abstract notion of a purchase order with a unique identifier.

The implementation of ISO Schematron used for this article.

You need to transform the Schematron schema at least once using the base stylesheet before you can use it to validate an XML document.

First of all, Schematron rules need to be defined in an XML format, as shown in Listing 4.

Since Schematron is itself XML, XForms can easily treat it as part of the data model for a form.

Schematron could be the basis for a reference implementation for the validating rule sets for HL7 Templates.

Schematron enables you to define flexible schemas that bend rather than break in the presence of unexpected content.

Furthermore, it provides a wide variety of samples, including a simple Schematron example similar to the one examined here.

I recommend learning Schematron (see Resources), but I'll just explain the major constructs in the listing.

My recent tutorial on Schematron offers an introduction to that useful, soon-to-be standard.

The last level, assertion, is typically implemented through Java code or through a dedicated assertion language such as Schematron.

Schematron is a rule-based language that uses XPath to express assertions about the content in an XML instance document.

Notice the two instances, as mentioned: one that references the XML instance data, and another that references the Schematron document.

Discover the benefits of using the Schematron standard, either on its own or in conjunction with other schema languages.

Schematron is one way of creating such tests in a platform independent way.

Schematron's abstract patterns serve as a mechanism for more flexible parameterization.

Even with the brief introduction to Schematron given so far, you can easily tell what this document does.

It also features constraints that you can express in Schematron that you cannot express in other languages.

Schematron is a very effective means to express business and model rules in systems using XML documents.

Overall, this Schematron device could make you rethink the way you design XML schemata -- all for the better.

With Schematron, you can add additional rules to another Schematron rule set more easily than modifying an XML schema.

This implies that the supplied document passed both the XML schema and Schematron validation steps.

Schematron was inspired by many of the ideas in XSLT, including the use of variables to help simplify code.

You can apply various Schematron rule sets individually as required by processes and by organizations.

Sometimes, Schematron constraints are contained within an XML Schema document, usually within XML Schema appinfo elements.

As you can see, the basic mechanism of Schematron abstract patterns is very simple.

Schematron currently doesn't offer the possibility of reporting straight back to the application.

In the tutorial and in this article, I use the term candidate XML to describe the XML file against which a Schematron schema is invoked.

Listing 2 is Schematron to generate a report of the request timestamp and resource type.

The first one is applying the Schematron XSL stylesheet to the incoming request XML document.

OAGIS supports a multistage validation mechanism based in Schematron assertions.

W3C XML Schema, Schematron, and the MIME type system have published popular constraint mechanisms.

Schematron implementations can now select the right diagnostic based on the language expected.

The second option is to complement the XML schemas with Schematron rules (see Resources).

To go a step further and validate the content of XML documents, a language called Schematron is used.

Other validation methods such as Schematron can be used as the validation layer for validating codes.

You can assign a value to the variables in Schematron using the let instruction.

Schematron is suitable for partial structure and HL7 CDA content constraints, which is highly appropriate for HL7 Templates.

A BICS document can have constraints of varying types -- for example, multiple schemas and a Schematron assertion schema.

This is similar to the most common mechanism for Schematron validation.

This makes Schematron very useful not only as a standalone schema language, but also as a complement to other schema languages.

This makes Schematron useful not only as a standalone schema language, but also as a complement to other schema languages.

A Schematron author can also provide text that is applicable when a condition is violated.

With its small tag set and use of familiar syntax such as XPath, Schematron is easy to learn and write, yet powerful.

Advanced Schematron features open up extraordinary possibilities for XML schemata

Discover the flexibility of Schematron abstract patterns

Listing 10 is a complete Schematron example that combines Listings