Processing of structured documents Spring 2002, Part 2 Helena Ahonen-Myka

Processing of structured documents

Spring 2002, Part 2Helena Ahonen-Myka

2

XML Namespaces

An XML document may contain multiple markup vocabularies

reuse of existing markup, e.g. including HTML markup in some document type

An XML namespace is a collection of names, identified by a URI reference, which are used in XML documents as element types and attribute names

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Author A writes a document:

<?xml version=”1.0”?><references> <name>Macmillan</name> <link href=”http://www.mcp.com”/> <name>ABC News</name> <link href=”http://www.abcnews.com”/></references>

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Author B adds some rating….

<?xml version=”1.0”?><references> <name>Macmillan</name> <link href=”http://www.mcp.com”/> <rating>5 stars</rating> <name>ABC News</name> <link href=”http://www.abcnews.com”/> <rating>3 stars</rating></references>

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Also Author C wants to add some rating...

<?xml version=”1.0”?><references> <name>Macmillan</name> <link href=”http://www.mcp.com”/> <rating>G</rating> <name>ABC News</name> <link href=”http://www.abcnews.com”/> <rating>PG</rating></references>

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Author D would like to combine the documents...

<?xml version=”1.0”?><references> <name>Macmillan</name> <link href=”http://www.mcp.com”/> <rating>5 stars</rating> <rating>G</rating> <name>ABC News</name> <link href=”http://www.abcnews.com”/> <rating>3 stars</rating> <rating>PG</rating></references>

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Which rating? -> different names

<?xml version=”1.0”?><references> <name>Macmillan</name> <link href=”http://www.mcp.com”/> <qa-rating>5 stars</qa-rating> <pa-rating>G</pa-rating> <name>ABC News</name> <link href=”http://www.abcnews.com”/> <qa-rating>3 stars</qa-rating> <pa-rating>PG</pa-rating></references>

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Namespaces give a disciplined method for naming

<?xml version=”1.0”?><references xmlns:qa=”http://joker.com/2000/star-rating” xmlns:pa=”http://penguin.xmli.com/2000/review” xmlns=”http://pineapplesoft.com/1999/ref”> <name>Macmillan</name> <link href=”http://www.mcp.com”/> <qa:rating>5 stars</qa:rating> <pa:rating>G</pa:rating> ...</references>

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Namespacesxmlns:qa=”http://joker.com/2000/star-rating”

qa: prefix http://joker.com/2000/star-rating

the namespacea unique name (URI guarantees): no need to retrieve

anything from the address

xmlns=” http://pineapplesoft.com/1999/ref”> the default namespace elements without prefixes belong to this

namespacereferences, name, link

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Namespaces

qa:rating a qualified name (Qname)

scoping: The namespace is valid for the element where

it is declared and all the elements within its content

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Scoping

<?xml version=”1.0”?><ref:references xmlns:ref=”http://pineapplesoft.com/1999/ref”> <ref:name>Macmillan</ref:name> <ref:link href=”http://www.mcp.com”/> <pa:rating xmlns:pa=”http://penguin.xmli.com/2000/review”>G</pa:rating> <ref:name>ABC News</ref:name> <ref:link href=”http://www.abcnews.com”/> <qa:rating xmlns:qa=”http://joker.com/2000/star-rating”> 3 stars</qa:rating></ref:references>

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Namespaces and DTD

XML 1.0 DTDs are not namespace-awareall the elements and attributes that are in

some namespace have to be declared using the corresponding prefix

for elements with prefix ’pre’ : an attribute ’xmlns:pre’ has to be declared

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Namespaces and DTD

<?xml version=”1.0”?><!DOCTYPE ref:references [<!ELEMENT ref:references (ref:name, ref:link, (pa:rating | qa:rating)*)+><!ATTLIST ref:references xmlns:ref CDATA #REQUIRED><!ELEMENT ref:name (#PCDATA)><!ELEMENT ref:link EMPTY><!ATTLIST ref:link href CDATA #REQUIRED><!ELEMENT pa:rating (#PCDATA)><!ATTLIST pa:rating xmlns:pa CDATA #REQUIRED><!ELEMENT qa:rating (#PCDATA)><!ATTLIST qa:rating xmlns:qa CDATA #REQUIRED>]>

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DTD: external and internal subsets

external and internal subset make up the DTD; internal has higher precedence

syntax: <!DOCTYPE root-type-name SYSTEM ”ex.dtd”  [  ]>

internal subset may declare new elements (with attributes) or new attributes for existing elements

namespaces facilitate the control of name conflicts

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Namespaces and XML Schema

An XML Schema document contains declarations of namespaces that are used in the document e.g. xmlns:xsd=”http://www.w3.org/2001/XMLSchema”

for the elements with special XML Schema semantics

Target namespace: ~these definitions included in this schema give definition to this namespace targetNamespace=”uri:mywork”

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In XML Schema, schema components from different target namespaces can be used together

-> enables the schema validation of instance content defined across multiple namespaces

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XML Information set

An XML document’s information set consists of a number of information items

an information item is an abstract description of some part of an XML document mainly to be used in other specifications

each information item has a set of associated named properties

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XML Information set

Tree structure provided by the processor (no special interface is specified)

e.g. entities expanded to their replacement text, attributes with their default values

properties: e.g. for each element its child elements and attributes

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Information items

document information itemelement information itemsattribute information itemsprocessing instruction information

itemsunexpanded entity reference

information itemscharacter information items

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Information items (cont.)

comment information itemsdocument type declaration

information itemunparsed entity information itemsnotation information itemsnamespace information items

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Example: document information item

There is exactly one document information item in the information set

all information items are accessible from the properties of the document information item, either directly or indirectly through the properties of other information items

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Example: document information item

Properties: children document element notations unparsed entities base URI character encoding scheme standalone version all declarations processed

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Example: element information items

There is an element information item for each element appearing in the XML document

one of the element information items is the value of the document element property of the document information item (root element)

all other element information items are accessible recursively

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Example: element information items

An element information item has the following properties: namespace name local name prefix children attributes namespace attributes in-scope namespaces base URI parent

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Example

<?xml version=”1.0”?>

<msg:message doc:date=”19990421”

xmlns:doc=”http://doc.example.org/namespaces/doc”

xmlns:msg=”http://message.example.org/”

>Phone home!</msg:message>

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The information set for the sample document

A document information iteman element information item with

namespace name ”http://message.example.org/”, local part ”message”, and prefix ”msg”

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The information set for the sample document (cont.)

an attribute information item with the namespace name ”http://doc.example.org/namespaces/doc”, local part ”date”, prefix ”doc”, and normalized value ”19990421”

three namespace information items for the http://www.w3.org/XML/1998/namespace, http://doc.example.org/namespaces/doc, http://message.example.org namespaces

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The information set for the sample document (ctnd.)

Two attribute information items for the namespace attributes

eleven character information items for the character data

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XML 1.0 reporting requirements

For instance: an XML processor must always provide all

characters in a document that are not part of markup to the application

a validating XML processor must inform the application which of the character data in a document is white space appearing within element content

an XML processor must normalize line-ends to LF before passing them to the application

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XML 1.0 reporting requirements (ctnd.)

A validating XML processor must include the replacement text of an entity in place of an entity reference

an XML processor must supply the default value of attributes declared in the DTD for a given element type but not appearing in the element’s start tag

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What is not in the information set? For instance,

the document type name the difference between the two forms of an

empty element: <foo/> and <foo></foo> the order of attributes within a start-tag white space within start-tags (other than

significant white space in attribute values) and end-tags

the difference between CR, CR-LF, and LF line termination

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XML Schema

DTDs have drawbacks:DTDs have drawbacks: they can only define the element structure and attributes they cannot define any database-like constraints for

elements: Value (min, max, etc.) Type (integer, string, etc.)

DTDs are not written in XML and cannot thus be processed with the same tools as XML documents, XSL(T), etc.

difficult to combine different vocabularies (namespaces)

XML SchemasXML Schemas: are written in XML avoid most of the DTD drawbacks

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XML Schema

XML Schema Part 1: Structures:XML Schema Part 1: Structures: Element structure definition as with DTD: Elements,

attributes, also enhanced ways to control structures

XML Schema Part 2: Datatypes:XML Schema Part 2: Datatypes: Primitive datatypes (string, boolean, float, etc.) Derived datatypes from primitive datatypes (time,

recurringDate) Constraining facets for each datatype (minLength,

maxLength, pattern, precision, etc.)

The following is based on:The following is based on: XML Schema Part 0: Primer (2.5.2001)

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Reminder: DTD declarations

<!ELEMENT name (fname+, lname)><!ELEMENT address (name, street,

(city, state, zipcode) | (zipcode, city))>

<!ELEMENT contact (address, phone*, email?)>

<!ELEMENT fname (#PCDATA)>

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<?xml version=”1.0”?><purchaseOrder orderDate=1999-10-20”> <shipTo country=”US”> <name>Alice Smith</name>

<street>123 Maple Street</street><city>Mill Valley</city><state>CA</state><zip>90952</zip>

</shipTo>

A sample document

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<billTo country=”US”> <name>Robert Smith</name>

<street>8 Oak Avenue</street><city>Old Town</city><state>PA</state><zip>95819</zip>

</billTo>

<comment>Hurry, my lawn is going wild!</comment>

Continues...

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<items><items> <item partNum="872-AA"><item partNum="872-AA"> <productName>Lawnmower</productName><productName>Lawnmower</productName> <quantity>1</quantity><quantity>1</quantity> <price>148.95</price><price>148.95</price> <comment>Confirm this is electric</comment><comment>Confirm this is electric</comment> </item></item> <item partNum="926-AA"><item partNum="926-AA"> <productName>Baby Monitor</productName><productName>Baby Monitor</productName> <quantity>1</quantity><quantity>1</quantity> <price>39.98</price><price>39.98</price> <shipDate>1999-05-21</shipDate><shipDate>1999-05-21</shipDate> </item></item> </items></items></purchaseOrder> </purchaseOrder>

… continues

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DTD

<!ELEMENT purchaseOrder (shipTo, billTo, comment?, items) >

<!ATTLIST purchaseOrder orderDate CDATA #REQUIRED>

<!ELEMENT shipTo (name, street, city, state, zip)>

<!ATTLIST shipTo country CDATA #REQUIRED>

<!ELEMENT billTo (name, street, city, state, zip)>

<!ATTLIST billTo country CDATA #REQUIRED>

<!ELEMENT comment (#PCDATA)>

<!ELEMENT items (item+)>

<!ELEMENT name (#PCDATA)>

<!ELEMENT street (#PCDATA)>

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DTD continues

<!ELEMENT city (#PCDATA)>

<!ELEMENT state (#PCDATA)>

<!ELEMENT zip (#PCDATA)>

<!ELEMENT item (productName, quantity, USPrice, (comment |

shipDate))>

<!ATTLIST item partNum CDATA #REQUIRED>

<!ELEMENT productName (#PCDATA)>

<!ELEMENT quantity (#PCDATA)>

<!ELEMENT USPrice (#PCDATA)>

<!ELEMENT shipDate (#PCDATA)>

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Complex and simple types

Schema defines types for elements and attributes

complex types: allow elements in their content and may have attributes

simple types: cannot have element content and cannot have attributes

elements can have complex or simple types, attributes can have simple types

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XML Schema: structure<xsd:schema

xmlns:xsd=”http://www.w3.org/2001/XMLSchema”>

<xsd:annotation> … </xsd:annotation>

<xsd:element name=”purchaseOrder” type=”PurchaseOrderType”/>

<xsd:element name=”comment” type=”xsd:string”/>

<xsd:complexType name=”PurchaseOrderType”>

<xsd:sequence>… </xsd:sequence>

<xsd:attribute name=”orderDate” type=”xsd:date”/>

</xsd:complexType>

…

</xsd:schema>

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USAddress type

<xsd:complexType name=”USAddress” > <xsd:sequence> <xsd:element name=”name” type=”xsd:string” /> <xsd:element name=”street” type=”xsd:string” /> <xsd:element name=”city” type=”xsd:string” /> <xsd:element name=”state” type=”xsd:string” /> <xsd:element name=”zip” type=”xsd:decimal” /> </xsd:sequence> <xsd:attribute name=”country” type=”xsd:NMTOKEN” fixed=”US” /></xsd:complexType>

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PurchaseOrderType

<xsd:complexType name=”PurchaseOrderType”> <xsd:sequence> <xsd:element name=”shipTo” type=”USAddress” /> <xsd:element name=”billTo” type=”USAddress” /> <xsd:element ref=”comment” minOccurs=”0” /> <xsd:element name=”items” type=”Items” /> </xsd:sequence> <xsd:attribute name=”orderDate” type=”xsd:date” /></xsd:complexType>

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Shared types, references

element declarations for shipTo and billTo associate different element names with the same complex type

attribute declarations must reference simple types

element comment declared on the top level of the schema (here reference only)

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Occurrence constraints

minOccurs, maxOccurs (defaults: 1) minOccurs: minimun number of times

an element may appear element is optional, if minOccurs = 0 maxOccurs: maximum number of

times an element may appearattributes may appear once or not

at all

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Attributes use, default and fixed (in attribute declarations)

Attribute ”use” is used in an attribute declaration to indicate whether the attribute is ’required’, ’optional’ or ’prohibited’

default value may be provided if ’optional’ is set if the instance does not give the value

the default is used

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Attributes use, default and fixed (in attribute declarations)

Attribute ”fixed” the value of the attribute is the value of

”fixed”

<xsd:attribute name=”temp1” type=”xsd:decimal” use=”optional” default=”37” />

<xsd:attribute name=”temp2” type=”xsd:decimal” use=”optional” fixed=”37” />

<xsd:attribute name=”temp2” type=”xsd:decimal” use=”required” fixed=”37” />

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Items<xsd:complexType name="Items"><xsd:complexType name="Items"> <xsd:sequence><xsd:sequence> <xsd:element name="item" minOccurs="0" maxOccurs="unbounded"><xsd:element name="item" minOccurs="0" maxOccurs="unbounded"> <xsd:complexType><xsd:sequence><xsd:complexType><xsd:sequence> <xsd:element name=”productName” type=”xsd:string” /><xsd:element name=”productName” type=”xsd:string” /> <xsd:element name="quantity"><xsd:element name="quantity"> <xsd:simpleType><xsd:simpleType>

<xsd:restriction base="xsd:positiveInteger"><xsd:restriction base="xsd:positiveInteger"> <xsd:maxExclusive value="100"/><xsd:maxExclusive value="100"/>

</xsd:restriction></xsd:restriction> </xsd:simpleType></xsd:simpleType> </xsd:element></xsd:element> <xsd:element name="USprice" type="xsd:decimal"/><xsd:element name="USprice" type="xsd:decimal"/> <xsd:element ref="comment" minOccurs="0"/><xsd:element ref="comment" minOccurs="0"/> <xsd:element name="shipDate" type="xsd:date”<xsd:element name="shipDate" type="xsd:date” minOccurs="0"/>minOccurs="0"/> </xsd:sequence></xsd:sequence> <xsd:attribute name="partNum" type="Sku” use=”required”/><xsd:attribute name="partNum" type="Sku” use=”required”/> </xsd:complexType></xsd:complexType> </xsd:element></xsd:sequence></xsd:element></xsd:sequence></xsd:complexType></xsd:complexType>

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Anonymous type definitions

Schemas can be constructed by defining sets of named types such as PurchaseOrderType on the top level and then declaring elements such as purchaseOrder

if a type is used only once, it is more compactly defined as an anonymous type

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Anonymous type definitions

You can define anonymous types by the lack of ’type=’ in an element declaration and by the presence of an unnamed (simple or complex) type definition following the element name see the Items type definition

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Global elements and attributes

Global elements and attributes have declarations that appear as the children of the schema element

global elements and attributes can be referenced in one or more declarations using the ref attribute

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Global elements and attributes

global elements can appear in the instance document in the place where they have been referenced, or at the top level of the document

global declarations cannot contain references

global declarations cannot contain occurrence constraints

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Simple types

Built-in types e.g. string, integer, positiveInteger, decimal,

float, boolean, time, date, recurringDay, uriReference, language, ID, IDREF

must have XML Schema namespace prefixderived types

derived from built-in and other derived types by defining restrictions to the base type

each base type has a set of facets that can be used for restrictions

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Facets

XML Schema defines 15 facets e.g. string has facets: length,

minLength, maxLength, pattern, enumeration

e.g. integer has facets: pattern, enumeration, maxInclusive, maxExclusive, minInclusive, minExclusive, precision, scale

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Defining a new type of integer

<xsd:simpleType name=”myInteger”>

<xsd:restriction base=”xsd:integer”>

<xsd:minInclusive value=”10000”/>

<xsd:maxInclusive value=”99999”/>

</xsd:restriction>

</xsd:simpleType>

New type whose range of values is between 10000 and 99999

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Patterns

<xsd:simpleType name=”Sku”><xsd:simpleType name=”Sku”> <xsd:restriction base=”xsd:string”><xsd:restriction base=”xsd:string”> <xsd:pattern value="\d{3}-[A-Z]{2}"/><xsd:pattern value="\d{3}-[A-Z]{2}"/> <xsd:restriction><xsd:restriction></xsd:simpleType></xsd:simpleType>

”three digits followed by a hyphen followed by two upper-case ASCII letters”

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Enumeration facet

<xsd:simpleType name=”USState”>

<xsd:restriction base=”xsd:string”>

<xsd:enumeration value=”AK”/>

<xsd:enumeration value=”AL”/>

<xsd:enumeration value=”AR”/>



</xsd:restriction>

</xsd:simpleType>

Limits values to a set of distinct values

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List types

List types are comprised of sequences of simple types

<xsd:element name=”listOfMyInt” type=”listOfMyIntType”>

<xsd:simpleType name=”listOfMyIntType”>

<xsd:list itemtype=”myInteger”/>

</xsd:simpleType>

instance:

<listOfMyInt>20003 15037 95977 95945</listOfMyInt>

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Union types

Type can be chosen from a set:

<xsd:element name=”zips” type=”zipUnion”>

<xsd:simpleType name=”zipUnion”>

<xsd:union memberTypes=”USState listOfMyIntType”/>

</xsd:simpleType>

<zips>CA</zips>

<zips>95630 95977 95945</zips>

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Element content

How to define attributes for elements with simple type content? In instance: <internationalPrice currency=”EUR”>423.45</internationalPrice> in the sample schema: <xsd:element name=”USPrice” type=”xsd:decimal”/> comes

close

but simple types cannot have attributes -> a complex type has to be defined

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Element content

New complex type is derived from type decimal

<xsd:element name=”internationalPrice>

<xsd:complexType>

<xsd:simpleContent>

<xsd:extension base=”xsd:decimal”>

<xsd:attribute name=”currency” type=”xsd:string” />

</xsd:extension>

</xsd:simpleContent>

</xsd:complexType>

</xsd:element>

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Mixed content

Element contains both character data and subelements

<letterBody>

<salutation>Dear Mr.<name>Robert Smith</name>.</salutation>

Your order of <quantity>1</quantity> <productName>Baby

Monitor</productName> shipped from our warehouse on

<shipDate>1999-05-21</shipDate> …

</letterBody>

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Mixed content<xsd:element name=”letterBody”> <xsd:complexType mixed=”true”> <xsd:sequence> <xsd:element name=”salutation”> <xsd:complexType mixed=”true”> <xsd:sequence> <xsd:element name=”name” type=”xsd:string”/> </xsd:sequence> </xsd:complexType> </xsd:element> <xsd:element name=”quantity” type=”xsd:positiveInteger”/> … </xsd:sequence></xsd:complexType></xsd:element>

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Empty content

Assume we want the internationalPrice element to have both the unit of currency and the price as attribute values: <internationalPrice currency=”EUR”

value=”423.45” />

i.e. the element has no contentsolution: no elements defined in the

content model

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Empty content

<xsd:element name=”internationalPrice” <xsd:complexType> <xsd:complexContent> <xsd:restriction base:”xsd:anyType”> <xsd:attribute name=”currency” type=”xsd:string” /> <xsd:attribute name=”value” type=”xsd:decimal” /> </xsd:restriction> </xsd:complexContent> </xsd:complexType></xsd:element>

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Shorthand for empty complex type

<xsd:element name=”internationalPrice” <xsd:complexType> <xsd:attribute name=”currency” type=”xsd:string” /> <xsd:attribute name=”value” type=”xsd:decimal” /> </xsd:complexType></xsd:element>

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anyType

The anyType seen in the definition for an empty content model represents an abstraction which is the base type from which all simple and complex types are derived

anyType does not constrain its content in any way

can be used like other types is a default if no type is specified

<xsd:element name=”anything” />

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Building content models

<xsd:sequence>: fixed order<xsd:choice>: (1) choice of

alternatives<xsd:group>: grouping (also named)<xsd:all>: no order specified

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Nested choice and sequence groups

<xsd:complexType name=”PurchaseOrderType”> <xsd:sequence> <xsd:choice> <xsd:group ref=”shipAndBill” /> <xsd:element name=”singleUSAddress” type=”USAddress” /> </xsd:choice> <xsd:element name=”items” type=”Items” /> </xsd:sequence>

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Nested choice and sequence groups

<xsd:group name=”shipAndBill”> <xsd:sequence> <xsd:element name=”shipTo” type=”USAddress” /> <xsd:element name=”billTo” type=”USAddress” /> </xsd:sequence></xsd:group>

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An ’all’ group

An all group: all the elements in the group may appear once or not at all, and they may appear in any order

limited to the top-level of any content model

has to be the only child at the topgroup’s children must all be individual

elements (no groups), and no element in the content model may appear more than once

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An ’all’ group

<xsd:complexType name=”PurchaseOrderType”> <xsd:all> <xsd:element name=”shipTo” type=”USAddress” /> <xsd:element name=”billTo” type=”USAddress” /> <xsd:element ref=”comment” minOccurs=”0” /> <xsd:element name=”items” type=”Items” /> </xsd:all> <xsd:attribute name=”orderDate” type=”xsd:date” /> </xsd:complexType>

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Attribute groups

Also attribute definitions can be grouped and named

<xsd:element name=”item” > <xsd:complexType> <xsd:sequence> … </xsd:sequence> <xsd:attributeGroup ref=”ItemDelivery” /> </xsd:complexType></xsd:element>

<xsd:attributeGroup name=”ItemDelivery”> <xsd:attribute name=”partNum” type=”SKU” /> …</xsd:attributeGroup>

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An XML Schema document contains declarations of namespaces that are used in the document e.g. xmlns:xsd=”http://www.w3.org/2001/XMLSchema”

for the elements with special XML Schema semantics

Target namespace: ~these definitions included in this schema give definition to this namespace targetNamespace=”uri:mywork”

75


In XML Schema, schema components from different target namespaces can be used together

-> enables the schema validation of instance content defined across multiple namespaces

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Importing schema declarations

Every top-level schema component is associated with a target namespace (or, explicitly, with none, if the target namespace is not defined)

a component may refer to another component that is in a different namespace, using an import element

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Import

<schema xmlns=”http://www.w3.org/2001/XMLSchema” xmlns:html=”http://www.w3.org/1999/xhtml” targetNamespace=”uri:mywork” xmlns:my=”uri:mywork”>

<import namespace=”http://www.w3.org/1999/xhtml”>…<complexType name=”myType”> <sequence> <element ref=”html:p” minOccurs=”0”/> </sequence> …</complexType><element name=”myElt” type=”my:myType”/></schema>

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Type libraries

As XML schemas become more widespread, schema authors will want to create simple and complex types that can be shared and used as the basic building blocks for building new schemas

XML Schemas already provide types that play this role: the simple types

other examples: currency, units of measurement, business addresses

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Example: currencies

<schema targetNamespace=”http://www.example.com/Currency” xmlns:c=”http://www.example.com/Currency” xmlns=”http://www.w3.org/2000/08/XMLSchema”><complexType name=”Currency”> <simpleContent> <extension base=”decimal”> <attribute name=”name”> <simpleType> <restriction base=”string”> <enumeration value=”AED”/>

<enumeration value=”AFA” /> <enumeration value=”ALL” /> …

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Extending content models

Mixed content models an element can contain, in addition to

subelements, also arbitrary character data

import an element can contain elements whose types

are imported from external namespaces e.g. this element may contain an HTML p

element here

more flexible way: any element, any attribute

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Example<purchaseReport

xmlns=”http://www.example.com/Report”><regions>  </regions><parts>  </parts><htmlExample> <table xmlns=”http://www.w3.org/1999/xhtml” border=”0” width=”100%”> <tr> <th align=”left”>Zip Code</th> <th align=”left”>Part Number </th> <th align=”left”>Quantity</th> </tr> <tr><td>95819</td><td> </td> <td> </td></tr> <tr><td> </td><td>872-AAA</td><td>1</td></tr> ...

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Including an HTML table

To permit the appearance of HTML in the instance document we modify the report schema by declaring the content of the element htmlExample by the any element

in general, an any element specifies that any well-formed XML is permissible in a type’s content model

in the example, we require the XML to belong to the namespace http://www.w3.org/1999/xhtml -> the XML should be XHTML

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Schema declaration with any

<element name=”purchaseReport”> <complexType> <sequence> <element name=”regions” type=”r:RegionsType”/> <element name=”parts” type=”r:PartsType”/> <element name=”htmlExample”> <complexType> <sequence> <any namespace=”http://www.w3.org/1999/xhtml” minOccurs=”1” maxOccurs=”unbounded” processContents=”skip”/> </sequence> ...

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Schema validation

The attribute processContents skip: no validation strict: an XML processor is obliged to obtain

the schema associated with the required namespace and validate the HTML appearing within the HTMLExample element

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anyAttribute

<element name=”htmlExample”> <complexType> <sequence> <any namespace=”http://www.w3.org/1999/xhtml” minOccurs=”1” maxOccurs=”unbounded” processContents=”skip”/> </sequence> <anyAttribute namespace=”http://www.w3.org/1999/xhtml”/> </complexType></element>

Documents

Processing of structured documents Spring 2002, Part 2 Helena Ahonen-Myka