I am developing an XSD (v1.0 although I could switch to 1.1) which will be further annotated by customers to describe specific constraints of their business exchanges. Examples of such additional constraints include xs:fixed, xs:maxLength, etc. During validation, I need violation of these "supplementary" rules to be treated differently. However, I do not see any standard way to "trap" errors in an XSD so that I can handle them. I can use Xerces or Saxon for validation.
You seem to be seeking two things:
a) the ability to distinguish customer-added facets from the ones that you have added
b) facet validation to be treated as non-fatal
a) is impossible unless your own XSD contains zero facets. I cannot think of any way that the XML processor could know whether a facet was in the original XML, or added by a customer.
b) is offered by some XML processors - look for APIs that allow you to supply your own error handler.
Also, note that 'additional constraints' must be limited to simple type facets only. In general it is not possible for a validating XML processor to continue after an unexpected tag, or a tag that repeats too many times/too few times.
Related
I would like to to create a sequence diagram to show some interaction, and then use that sequence diagram as an interaction occurrence (sub-sequence) on other sequence diagrams. The point is I would like to apply the sub-sequence each time to a different object instance that is involved in the interaction in the sub-sequence. In my case the instances are simply various file artifacts. Is there any legitimate way of doing this prescribed by UML?
EDIT: some more clarification of my context:
I have 2 main sequence diagrams where I want to reuse the sub-sequence as an interaction occurrence
on the 1st main sequence there is one file for which the sub-sequence has to be applied 3 times
on the 2nd main sequence there are 3 different files for which the sub-sequence has to be applied 3 times
the files are read by the same object instance
I model reading from a file by a call arrow stereotyped as <<read>> to a on object instance which represents the file.
I need to reference the file somehow in the sub-sequence, but I haven't found a good and simple way of doing this.
Complicated, but formally (almost) correct solution with Collaborations
Just using InteractionUses is not enough, because this doesn't allow you to assign the actual roles in the main interaction to the generic roles of your used interaction.
Collaborations, CollaborationUses and Role Bindings can be used for this.
See my example here:
This defines a Collaboration with generic roles sender, relay and receiver and shows the interaction between them.
You can now use this collaboration in a concrete situation:
Class S uses the Collaboration two times with different role bindings to its parts (A, B and C are assumed to be able to send and receive Sig1).
With these definitions you can now create your main sequence diagram:
Unfortunately, this is not correct UML, even though there is an example in the specification (I filed an Issue https://issues.omg.org/browse/UMLR-768). You will have to fake this notation until the taskforce comes up with a fix. How to fake it, depends on how strict your tool implements the specification.
Advantage: formally correct and versatile solution, backed by an example in the specification
Disadvantage: complicated and difficult to explain, not completely usable, because of a bug in the specification
Basically there are three different ways to specify such situations.
Using a gate. Whith gates you specify the sequence with messages that start or end at a gate that is defined and in most tools (if usable at all) not shown explicitly. Instead it is modelled with messages starting or ending at the interaction border.
Similar as gates are lost and found messages. These are special messages that pass out the control to another sequence or returns from one. Such as in the case before you can define a set of further diagrams specifying the interaction in more details.
Using abstraction, which is my favorit for most of the cases. This means you extract the common interface from the classes and specify the interaction against the interface instead of the concrete classes.
Use an Interaction with Parameters:
Now we would like to reference the Lifelines of the main Interaction in the arguments of the InteractionUse. Unfortunately, in UML this is not possible, since arguments are ValueSpecifications and they cannot reference another modelelement.
However, NoMagic suggested and implemented an additional ValueSpecification, called ElementValue, that does exactly this. I think this would be a valuable addition to UML and hopefully it will be added some day. Up to then, only MagicDraw users can use this solution (as far as I know).
With this non standard element, we can model this:
The connection between the lifelines is now via the arguments for the parameters of the generic interaction. Technically the lifelines would not need to be explicitely covered by the Interaction Use, but I think that it makes sense to do it (shown in my tool with a non standard circle on the border of the Interaction Use).
Advantage:
compact and versatile solution, almost conformant to the standard
Disadvantage:
uses a non standard model element, currently only available to MagicDraw users.
pragmatic non conformant solution with covered lifelines:
The collaboration and parameter solutions allow to specify it (almost) formally correct. However, in many cases, a simplified model would be sufficient. In your case, for example, you only have two participants and they have different types. So, even though there is no formal connection between the lifelines of the used interaction, and those of the main interaction, there would be no ambiguity. You could use the covered attribute of the InteractionUse to specify, which of the lifelines (files) you are targeting at a specific InteractionUse. Could that be the pragmatic solution, you are looking for?
Advantage:
compact solution
Disadvantage:
not conformant to UML, ambiguous in more complicated situations
I have several schemas that inherit one or more elements from a collection of 'common' schemas. In this particular instance, I'm importing one of these schemas to make use of a single complex type defined in it.
When I generate the java objects from the schema, I get my schema types, and the element I referenced as expected, however I also get objects generated for the 30+ other types from the common schema.
I want to use the common schema, because I want to rely on automated builds for updating my schema when the common schema changes, but I do not want the extra java classes generated.
Suggestions ?
There's no out of the box approach to achieve what you want. The reason I am offering an opinion here is rather to point out (maybe for others) some issues one needs to take into account no matter which route ones go.
The 'extra' label is not always straightforward. Substitution group members are interesting. In Java, think about a class (A) using an interface (I), and a class (B:I) implementing (I). Some may say there's no dependency between A and B, while others would require B in the distribution. If you replace (I) with a concrete class, things become even less clear - consider that the substitution group head doesn't need to be abstract; or if the type of the substitution group head is anyType (Object in Java).
More so, if the XML processing was designed to accommodate xsi:type then it is even harder to tell (by looking at the schema) what is expected to work where.
Tools such as QTAssistant (I am associated with it) have a default setting that will pull in all strict dependencies (A and I above); and either ALL that might work (B above), or nothing else. Anything in between, the user needs to manually define what goes in the release. This is called automatic XSD refactoring and could be used easily in your scenario.
I need to select a modeling method for documenting extensions to an existing collection of web services. The method/tool needs to be used by tech business analysts. The existing API is defined in XML Schema. XML Schema work well with the one exception. Take a PaymentInformation class as an example. One partner might accept Visa and Mastercard as an example. Another also excepts Amex. We want to be able to extend PaymentInformation for PartnerA and PartnerB.
class PaymentInformation
method // CASH,CC
ccNumber
ccType // MC,V,AMEX
class PaymentInformationPartnerA
method // CASH,CC,PAYPAL
ccNumber
ccType // MC, V
The problem with XML Schema is that to apply a restriction to a class requires redefining the whole type. This seems like a maintenance nightmare. UML doesn't seem to support restricted strings (patterns, length, etc). What tool/method do you recommend for this? We have a preference, but not a requirement for Eclipse IDE.
You can add an UML constraint or a condition on your class. This is either a graphical note or directly an information hand coded on the UML metamodel.
The UML model is already an XMI 2.1 therefore like a XML but using specific rules.
Don't do that. If PaymentInformationPartnerA extends PaymentInformation then for all uses of PaymentInformation you can use PaymentInformationPartnerA, whereas you are saying that for some uses ( assigning a value to ccType of "AMEX" ) it is not covariant.
You're probably better off putting the constraint as a pre-condition of the endpoint receiving the message rather than as a constraint on the message type itself.
Does anybody know where I can find documentation on how to write annotation schemas for Callisto? I'm looking to write something a little more complicated than I can generate from a DTD -- that only gives me the ability to tag different kinds of text mentions. I'm looking to create a schema that represents a single type of relationship between five or six different kinds of textual mentions (and some of these types of mentions have attributes that I need to assign values to), and possibly having a second type of relationship between the first two instances of the first type of relationship.
(Alternatively, does anybody know of any software that would be better for this kind of schema? I've been looking at WordFreak, but it's a little clumsy, and it doesn't support attributes on its textual mentions.)
Creating an XML DTD with one XML tag for each type of textual mention (and attributes on the tags to indicate the attributes), and using an "id" attribute on every tag that the annotator has to fill in himself (a monotonically increasing integer). Then I used the DTD schema generator to create a Callisto schema.
I designed a data model which is represented by an XSD scheme.
The data model also provides the types that are being used as web service parameters in a WSDL descriptor.
I would like to send the XSD scheme around and ask the people involved to peer review the data model.
What tool or presentation method would you suggest to be used as a basis for peer reviews? The data model should be readable for non-skilled people, at least when it comes to the semantic meanings of the parameters
Edit:
To be more specific: Of course, syntactically, the scheme validates. Actually I'm already working on code which is based on JAXB generated classes. My goal is
to freeze the data model and thus
the input parameters
to make sure
nothing got lost or forgotten from a
semantic (in the meaning of
business-relevant) point of view.
Edit 2
I've been thinking about how it probably would be best to spread a datamodel around. I'm thinking of something like a JavaDoc for XSD schemas. Anyone knows if something like that exists? Basically it would be done with a set of XSLTs, right?
I know the following tools that generate documentation from XML Schema files (XSD):
xs3p
XSLT stylesheet that generates single XHTML from XSD
xsddoc
free / LGPL
mainly XSLT based
JavaDoc like output
see xsddoc examples
xnsdoc
improved commercial version of xsddoc
free for personal/educational use
JavaDoc like output
XSDdoc 2.0
commercial
JavaDoc like output
For small a XML schema, I would probably suggest using the xs3p XSLT stylesheet. For more a complex schema, I suggest using xsddoc.
I recommend using the XSD for something. Specifically, show some actual applications, with examples as real code.
Actual applications are what make a schema interesting. The examples don't have to be big, sophisticated or completely realistic. They just have to compile. Other people will want to copy and paste the code samples.
These examples are the "hello world" of the schema. And they act as a kind of unit test for the schema.
The closest thing to Javadoc for an XML schema that I've seen is running the Javadoc tool on source generated from the schema. This requires two things: 1) That your schema has internal annotation elements documenting it, and that 2) your source generator uses those annotations as Javadoc elements.
The very useful Oxygen XML developer also supports generating documentation, see
http://www.oxygenxml.com/xml_schema_documentation.html
(commercial, but there's a fully functional 30 day trial available)
I'll try it out now, need a simple way to generate a document with all types and available xsd:documentation description as a simple interface description...
** Disclosure : I work for Innovasys, the producer of the documentation tool mentioned below *
You could take a look at Innovasys Document! X. As well as automatically generating a structured and linked page for every element, simple type, complex type, group and attribute group it will also generate linked XSD diagrams (including sequences/choice etc.) and structure tables that include the annotations from your XSDs and make sense of the relationships between the elements in your schemas. The output is template based so you can adapt it to your preferred style and structure. It will build output to web ready html or compiled help files.
Uniquely it also includes a WYSIWYG editor that allows you author additional content to supplement the stuff that's automatically generated and the annotations from the XSD source - so you can provide additional contextual information for your peer review. There is also a Community Extensions feature that allows people viewing the generated output to record comments and feedback and that can be viewed and actioned directly from within Document! X.