24 02 14

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School of Industrial and Information Engineering Knowledge Engineering 2013–14 Test 4 – 24th September 2014 Part II Family name Given name(s) ID 3 7 pt. We need an XML language “L” to represent touristic paths. Each file contains at least one touristic point of interest (POI) and zero or more paths. POIs and paths can be mixed in any order. Each path contains the references to the POIs it connects and can refer to other similar paths. A path that refers to other paths can be marked as a “cluster”. Here is an example of an instance document: <paths> <poi code=”p1” name=Spiaggia” latitude=”41.244935” longitude=”9.181644”/> <poi code=”p2” name=”Monumento” latitude=”41.218357” longitude=”9.184169”/> <path id=”path1”><poi-ref id=”p1”/><poi-ref id=”p3”/></path> <poi code=”p3” name=”Ristorante” latitude=”41.222248” longitude=”9.219462” /> <path id=”path2” refers-to=”path1”><poi-ref id=”p1”/><poi-ref id=”p3”/></path> <path id=”path3” refers-to=”path1 path2” cluster=”true”> <poi-ref id=”p1”/> <poi-ref id=”p2”/> </path> </paths> 1) Write a DTD for L, describing all the required approximations and saying whether they can be removed using XSD and how (describe how in English, no XSD fragment required) 2) Write a document (with root “paths”) validated by the DTD, but not in L. 3) Write a simple java fragment that checks one characteristic you removed in the DTD approximation <!ELEMENT paths (path*,poi,(poi|path)*)> <!ELEMENT poi EMPTY> <!ELEMENT path poi-ref*> <!ELEMENT poi-ref ENPTY> <!ATTLIST poi code ID #REQUIRED name CDATA #REQUIRED latitude CDATA #IMPLIED longitude CDATA #IMPLIED> <!ATTLIST path id ID #REQUIRED refers-to IDREFS #IMPLIED cluster CDAPA #IMPLIED> <!ATTLIST poi-ref id IDREF #REQUIRED> approximations: can’t guarantee that ids in "refers-to" correspond to paths and…