- From: Stephan Zednik <zednis@rpi.edu>
- Date: Thu, 7 Feb 2013 13:30:38 -0700
- To: Curt Tilmes <Curt.Tilmes@nasa.gov>
- Cc: Luc Moreau <l.moreau@ecs.soton.ac.uk>, "public-prov-wg@w3.org" <public-prov-wg@w3.org>
- Message-Id: <E7878EC1-D7A9-40AB-B288-062185C9AC26@rpi.edu>
I have committed change to prov-core.xsd to use ordered elements for prov attributes. https://dvcs.w3.org/hg/prov/rev/3f1e31b0df28 I have also updated a few prov-xml test files in eg-40 to conform with the new required ordering of elements https://dvcs.w3.org/hg/prov/rev/f95aa1566db7 --Stephan On Feb 7, 2013, at 1:10 PM, Stephan Zednik <zednis@rpi.edu> wrote: > Sounds good. I will commit the change. > > --Stephan > > On Feb 7, 2013, at 1:06 PM, Curt Tilmes <Curt.Tilmes@nasa.gov> wrote: > >> I was going to suggest the order from PROV-DM section 5.7.2 and table 8, >> which appears to be alphabetical... >> >> Curt >> >> On 02/07/2013 01:39 PM, Stephan Zednik wrote: >>> How about alphabetical? >>> >>> --Stephan >>> >>> On Feb 7, 2013, at 9:57 AM, Stephan Zednik <zednis@rpi.edu> wrote: >>> >>>> Now I think it is time to determine what ordering we want to have. Should we use alphabetic ordering? order by expectations of usage? I don't have a preference except that we are consistent. >>>> >>>> --Stephan >>>> >>>> >>>> On Feb 7, 2013, at 4:12 AM, Curt Tilmes <Curt.Tilmes@nasa.gov> wrote: >>>> >>>>> Agreed. If we just explain clearly in the doc what the order is, anyone implementing can do it that way. >>>>> Most people will be using other tools to output the XML so the tool will hide the need for order from them >>>>> anyway. >>>>> >>>>> Curt >>>>> >>>>> On 2/7/13 4:40 AM, Stephan Zednik wrote: >>>>>> Ok. I am on-board with updating the schema to enforce element ordering on prov attributes. I like the idea of using jax bindings + simplify plugin but I think that is too complex a solution. >>>>>> >>>>>> --Stephan >>>>>> >>>>>> On Feb 7, 2013, at 1:47 AM, Luc Moreau <l.moreau@ecs.soton.ac.uk> wrote: >>>>>> >>>>>>> Hi Stephan, >>>>>>> >>>>>>> Response interleaved. >>>>>>> >>>>>>> On 07/02/2013 04:08, Stephan Zednik wrote: >>>>>>>> >>>>>>>> On Feb 6, 2013, at 4:58 PM, Luc Moreau <L.Moreau@ecs.soton.ac.uk> wrote: >>>>>>>> >>>>>>>> >>>>>>>>> Hi Stephan and Curt, >>>>>>>>> >>>>>>>>> It is good to keep choice in documentElement. You both introduced it. Let's not remove it. >>>>>>>>> >>>>>>>> I agree, but the choice in documentElement will lead to the same problem with JAXB that a choice in attributes does. >>>>>>>> >>>>>>> >>>>>>> I don't think the situation is the same. >>>>>>> A bundle/document has a containment relationship with respect to documentElements, whereas prov attributes, we want them >>>>>>> to appear as instance variables (with associated setters and getters). I am therefore fine, with all documentElments being >>>>>>> amalgamated in a single list. >>>>>>>> Both Document and Bundle classes generated by JAXB's xjc use a single list for all available elements in a documentElement. >>>>>>>> >>>>>>>> The generated code looks like the following: >>>>>>>> >>>>>>>> protected List<JAXBElement<?>> entityOrActivityOrWasGeneratedBy; >>>>>>>> >>>>>>>> /** >>>>>>>> * Gets the value of the entityOrActivityOrWasGeneratedBy property. >>>>>>>> * >>>>>>>> * <p> >>>>>>>> * This accessor method returns a reference to the live list, >>>>>>>> * not a snapshot. Therefore any modification you make to the >>>>>>>> * returned list will be present inside the JAXB object. >>>>>>>> * This is why there is not a <CODE>set</CODE> method for the entityOrActivityOrWasGeneratedBy property. >>>>>>>> * >>>>>>>> >>>>>>> >>>>>>> >>>>>>> We can easily improve on this, as I did in the provtoolbox: >>>>>>> See http://openprovenance.org/java/site/prov/apidocs/org/openprovenance/prov/xml/Document.html#getEntityOrActivityOrWasGeneratedBy() >>>>>>> >>>>>>> >>>>>>>> * <p> >>>>>>>> * For example, to add a new item, do as follows: >>>>>>>> * <pre> >>>>>>>> * getEntityOrActivityOrWasGeneratedBy().add(newItem); >>>>>>>> * </pre> >>>>>>>> * >>>>>>>> * >>>>>>>> * <p> >>>>>>>> * Objects of the following type(s) are allowed in the list >>>>>>>> * {@link JAXBElement }{@code <}{@link Association }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link EmptyCollection }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Specialization }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Removal }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Dictionary }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Organization }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link EmptyDictionary }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Plan }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Start }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Agent }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Collection }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Mention }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Generation }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link SoftwareAgent }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Derivation }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link KeyValuePair }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Object }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Communication }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Attribution }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Delegation }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Entity }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Influence }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Usage }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Alternate }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Membership }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Bundle }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link End }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Insertion }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Activity }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Invalidation }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Person }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Revision }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link Quotation }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link PrimarySource }{@code >} >>>>>>>> * {@link JAXBElement }{@code <}{@link DictionaryMembership }{@code >} >>>>>>>> * >>>>>>>> * >>>>>>>> */ >>>>>>>> public List<JAXBElement<?>> getEntityOrActivityOrWasGeneratedBy() { >>>>>>>> if (entityOrActivityOrWasGeneratedBy == null) { >>>>>>>> entityOrActivityOrWasGeneratedBy = new ArrayList<JAXBElement<?>>(); >>>>>>>> } >>>>>>>> return this.entityOrActivityOrWasGeneratedBy; >>>>>>>> } >>>>>>>> >>>>>>>> >>>>>>>>> My concern about choice in prov attributes is that they lead, by default, to non natural object mapping with jaxb. I believe jaxb matters because jaxb is a community standard reaching well beyond the java community. >>>>>>>>> >>>>>>>> I agree. Would having a section in the FAQ which analyzes the problem in the context of a specific ORM technology and provides possible solutions (hints and/or alternate schemas) for that technology be satisfiable? >>>>>>>> >>>>>>>> >>>>>>> >>>>>>> alternate schemas is challenging, since you want any xml compatible with prov-xml to be readable by a jaxb-friendly schema. >>>>>>>> Also, looking at the JAXB generated class I think the manner in which the schema defines and uses prov:ref will result in a mapping that is not natural. >>>>>>>> >>>>>>>> The following components from the schema >>>>>>>> >>>>>>>> <xs:complexType name="Generation"> >>>>>>>> <xs:sequence> >>>>>>>> <xs:element name="entity" type="prov:IDRef"/> >>>>>>>> <xs:element name="activity" type="prov:IDRef" minOccurs="0"/> >>>>>>>> <xs:element name="time" type="xs:dateTime" minOccurs="0"/> >>>>>>>> <xs:choice minOccurs="0" maxOccurs="unbounded"> >>>>>>>> <xs:element ref="prov:location"/> >>>>>>>> <xs:element ref="prov:role"/> >>>>>>>> <xs:element ref="prov:label"/> >>>>>>>> <xs:element ref="prov:type"/> >>>>>>>> <xs:any namespace="##other"/> >>>>>>>> </xs:choice> >>>>>>>> </xs:sequence> >>>>>>>> <xs:attribute ref="prov:id"/> >>>>>>>> </xs:complexType> >>>>>>>> >>>>>>>> <!-- note, this is not xs:IDREF --> >>>>>>>> <xs:complexType name="IDRef"> >>>>>>>> <xs:attribute ref="prov:ref" use="required" /> >>>>>>>> </xs:complexType> >>>>>>>> >>>>>>>> result in class members with type IDRef >>>>>>>> >>>>>>>> protected IDRef entity; >>>>>>>> protected IDRef activity; >>>>>>>> >>>>>>>> Whose class is defined like so: >>>>>>>> >>>>>>>> >>>>>>> >>>>>>> Here, provtoolbox maps as follows: >>>>>>> >>>>>>> http://openprovenance.org/java/site/prov/apidocs/org/openprovenance/prov/xml/Entity.html#getId() >>>>>>> >>>>>>> public QName getId() >>>>>>> >>>>>>> So, i think this works ok. >>>>>>> >>>>>>> Luc >>>>>>> >>>>>>> >>>>>>>> @XmlAccessorType(XmlAccessType.FIELD) >>>>>>>> @XmlType(name = "IDRef") >>>>>>>> public class IDRef { >>>>>>>> >>>>>>>> @XmlAttribute(name = "ref", namespace = MailScanner has detected a possible fraud attempt from "www.w3.org" claiming to be "http://www.w3.org/ns/prov#", required = true) >>>>>>>> protected QName ref; >>>>>>>> >>>>>>>> /** >>>>>>>> * Gets the value of the ref property. >>>>>>>> * >>>>>>>> * @return >>>>>>>> * possible object is >>>>>>>> * {@link QName } >>>>>>>> * >>>>>>>> */ >>>>>>>> public QName getRef() { >>>>>>>> return ref; >>>>>>>> } >>>>>>>> >>>>>>>> /** >>>>>>>> * Sets the value of the ref property. >>>>>>>> * >>>>>>>> * @param value >>>>>>>> * allowed object is >>>>>>>> * {@link QName } >>>>>>>> * >>>>>>>> */ >>>>>>>> public void setRef(QName value) { >>>>>>>> this.ref = value; >>>>>>>> } >>>>>>>> >>>>>>>> } >>>>>>>> >>>>>>>> I think our modeling of prov:ref will likewise cause confusion among ORM generated classes. >>>>>>>> >>>>>>>> --Stephan >>>>>>>> >>>>>>>> >>>>>>>>> Now, I am not expert in jaxb. There may well be standard jaxb annotations that allow us To support a natural object mapping with an xsd choice. If so, we should go for xsd:choice. >>>>>>>>> >>>>>>>>> Curt's suggestion of a plugin (-simple) is a good, as long as plugin is maintained, which with my jaxb experience, is not encouraging, especially. >>>>>>>>> >>>>>>>>> >>>>>>>>> In the absence of standard jaxb annotations that lead to natural jaxb mappings, my preference is to be conservative and go for ordered prov attributes. >>>>>>>>> >>>>>>>>> >>>>>>>>> Professor Luc Moreau >>>>>>>>> Electronics and Computer Science >>>>>>>>> University of Southampton >>>>>>>>> Southampton SO17 1BJ >>>>>>>>> United Kingdom >>>>>>>>> >>>>>>>>> On 6 Feb 2013, at 20:08, "Stephan Zednik" <zednis@rpi.edu> wrote: >>>>>>>>> >>>>>>>>> >>>>>>>>>> After having played around with JAB and gaining a better understanding of the problem I am more amenable to the idea of requiring element ordering for properties. >>>>>>>>>> >>>>>>>>>> I am still not sold on the idea of element ordering in documentElements and without that the generated class methods for Bundle will be a 'bag of hurt'. >>>>>>>>>> >>>>>>>>>> An alternate idea is a to have a section in the FAQ dedicated to providing ORM implementation-specific tips on how to generate 'nice' mappings. >>>>>>>>>> >>>>>>>>>> The plugin Curt has mentioned could be mentioned in a FAQ entry and we could provide an example of how to use external hints to JAXB. The FAQ could also contain links to a modified schema that uses ordered elements and is only intended to be used as a source for ORM mappings, but not as a schema to validate against. >>>>>>>>>> >>>>>>>>>> I think I like the second option best as it allows us to respond to ORM-mapping issues after the WG activity has completed and is a natural way to talk about implementation specific ORM issues. >>>>>>>>>> >>>>>>>>>> --Stephan >>>>>>>>>> >>>>>>>>>> On Feb 5, 2013, at 11:56 AM, Curt Tilmes <Curt.Tilmes@nasa.gov> wrote: >>>>>>>>>> >>>>>>>>>> >>>>>>>>>>> Luc, >>>>>>>>>>> >>>>>>>>>>> I haven't tested this yet, but is it possible that the jaxb >>>>>>>>>>> "Simplify" plugin could address this problem with jaxb? >>>>>>>>>>> >>>>>>>>>>> http://confluence.highsource.org/display/J2B/Simplify+Plugin >>>>>>>>>>> >>>>>>>>>>> It seems (again, untested), that you could use it and specify >>>>>>>>>>> some application hints for jaxb ("simplify:as-element-property") >>>>>>>>>>> for the attributes that would instruct jaxb to model >>>>>>>>>>> each attribute family (type, location, label, etc.) with >>>>>>>>>>> its own list rather than bundling them together as it >>>>>>>>>>> does by default with choices. >>>>>>>>>>> >>>>>>>>>>> Curt >>>>>>>>>>> >>>>>>>>>>> On 02/05/2013 01:37 AM, Luc Moreau wrote: >>>>>>>>>>> >>>>>>>>>>>> Hi Curt, >>>>>>>>>>>> >>>>>>>>>>>> Does the schema now impose an order on prov "attributes"? >>>>>>>>>>>> >>>>>>>>>>>> Without order, I have failed to define an object mapping (with jaxb) >>>>>>>>>>>> >>>>>>>>>>> that is useful from an OO perspective. Likewise, i have not managed to >>>>>>>>>>> define a meaningful ORM mapping. Now, this is my experience with these >>>>>>>>>>> tools, maybe somebody has succeeded. >>>>>>>>>>> >>>>>>>>>>>> In summary, The problem I encountered is as follows. If there is a >>>>>>>>>>>> >>>>>>>>>>> choice (instead of sequence) between say, prov:type, prov:location, >>>>>>>>>>> prov:label, all these elements are mapped to a single java method or a >>>>>>>>>>> single sql column. This results in non natural code or SQL queries. >>>>>>>>>>> >>>>>>>>>>>> Because of this, my preference is to keep these in a sequence. It does >>>>>>>>>>>> >>>>>>>>>>> not at all reduce expressivity, I think. >>>>>>>>>>> >>>>>>>>>>>> Professor Luc Moreau >>>>>>>>>>>> Electronics and Computer Science >>>>>>>>>>>> University of Southampton >>>>>>>>>>>> Southampton SO17 1BJ >>>>>>>>>>>> United Kingdom >>>>>>>>>>>> >>>>>>>>>>>> On 5 Feb 2013, at 01:17, "Curt Tilmes" <Curt.Tilmes@nasa.gov> wrote: >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>>> Last week, we also briefly mentioned the PROV-XML element >>>>>>>>>>>>> ordering issue, described here: >>>>>>>>>>>>> >>>>>>>>>>>>> https://www.w3.org/2011/prov/track/issues/572 >>>>>>>>>>>>> >>>>>>>>>>>>> Are there strong opinions about changing anything (either >>>>>>>>>>>>> arguments, or attributes or anything else from the way it >>>>>>>>>>>>> is now? >>>>>>>>>>>>> >>>>>>>>>>>>> Tracker, this is ISSUE-572. >>>>>>>>>>>>> >>>>>>>>>>>>> Curt >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>> -- >>>>>>>>>>> Curt Tilmes, Ph.D. >>>>>>>>>>> U.S. Global Change Research Program >>>>>>>>>>> 1717 Pennsylvania Avenue NW, Suite 250 >>>>>>>>>>> Washington, D.C. 20006, USA >>>>>>>>>>> >>>>>>>>>>> +1 202-419-3479 (office) >>>>>>>>>>> +1 443-987-6228 (cell) >>>>>>>>>>> globalchange.gov >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>> >>>>>>>>> >>>>>>>> >>>>>>> >>>>>>> -- >>>>>>> Professor Luc Moreau >>>>>>> Electronics and Computer Science tel: +44 23 8059 4487 >>>>>>> University of Southampton fax: +44 23 8059 2865 >>>>>>> Southampton SO17 1BJ email: l.moreau@ecs.soton.ac.uk >>>>>>> United Kingdom http://www.ecs.soton.ac.uk/~lavm >>>>>>> >>>>> >>>>> >>>>> -- >>>>> Curt Tilmes, Ph.D. >>>>> U.S. Global Change Research Program >>>>> 1717 Pennsylvania Avenue, NW, Suite 250 >>>>> Washington, D.C. 20006, USA >>>> >>> >> >> >> -- >> Curt Tilmes, Ph.D. >> U.S. Global Change Research Program >> 1717 Pennsylvania Avenue NW, Suite 250 >> Washington, D.C. 20006, USA >> >> +1 202-419-3479 (office) >> +1 443-987-6228 (cell) >> globalchange.gov >
Received on Thursday, 7 February 2013 20:31:31 UTC