diff --git a/Doc/Sda1/xmlschema.xml b/Doc/Sda1/xmlschema.xml
index e4f385e408fc2f99b6104354cb05e347c4fc6c05..87ebd4754d1985d017dd4367103e9e74b417ec8b 100644
--- a/Doc/Sda1/xmlschema.xml
+++ b/Doc/Sda1/xmlschema.xml
@@ -1,158 +1,157 @@
- <chapter xml:id="xmlSchema" version="5.0" xmlns="http://docbook.org/ns/docbook"
- xmlns:xlink="http://www.w3.org/1999/xlink"
- xmlns:xi="http://www.w3.org/2001/XInclude"
- xmlns:svg="http://www.w3.org/2000/svg"
- xmlns:m="http://www.w3.org/1998/Math/MathML"
- xmlns:html="http://www.w3.org/1999/xhtml"
- xmlns:db="http://docbook.org/ns/docbook">
-
-
- <title>Beyond well- formedness</title>
-
- <section xml:id="motivationSchema">
- <title>Motivation</title>
-
- <para>So far we are able to create XML documents containing
- hierarchically structured data. We may nest elements and thus create
- tree structures of arbitrary depth. The only restrictions being imposed
- by the XML standard are the constraints of well - formedness. For many
- purposes in software development this is not sufficient.</para>
-
- <para>A company named <productname>Softmail</productname> might
- implement an email system which uses <link
- linkend="memoWellAttrib">memo</link> document files as low level data
- representation serving as a persistence layer. Now a second company
- named <productname>Hardmail</productname> wants to integrate mails
- generated by <productname>Softmail</productname>'s system into its own
- business product. The <productname>Hardmail</productname> software
- developers might <emphasis>infer</emphasis> the logical structure of
- <productname>Softmail</productname>'s email representation but the
- following problems arise:</para>
-
- <itemizedlist>
- <listitem>
- <para>The logical structure will in practice become more complex:
- E-mails may contain attachments leading to multi part messages.
- Additional header information is required for standard Internet mail
- compliance. This adds additional complexity to the XML structure
- being mandatory for data representation. Relying only on
- well-formedness the specification of an internal E-mail format can
- only be achieved <emphasis>informally</emphasis>. Thus a rule like
- <quote>Each E-mail must have a subject</quote> may be written down
- in the specification. A software developer will code these rules but
- probably make mistakes as the set of rules grows.</para>
-
- <para>In contrast a RDBMS based solution offers to solve such
- problems in a declarative manner: A developer may use a <code>NOT
- NULL</code> constraint on a subject attribute of type
- <code>VARCHAR</code> thus inhibiting empty subjects.</para>
- </listitem>
-
- <listitem>
- <para>As <productname>Softmail</productname>'s product evolves its
- internal E-mail XML format is subject to change due to functional
- extensions and possibly bug fixes both giving rise to
- interoperability problems.</para>
- </listitem>
- </itemizedlist>
-
- <para>Generally speaking well formed XML documents lack grammar
- constraints as being available for programming languages. In case of
- RDBMS developers can impose primary-, foreign and <code>CHECK</code>
- constraints in a <emphasis>declarative</emphasis> manner rather than
- hard coding them into their applications (A solution bad programmers are
- in favour of though...). Various XML standards exist for declarative
- constraint definitions namely:</para>
-
- <itemizedlist>
- <listitem>
- <para>DTDs</para>
- </listitem>
-
- <listitem>
- <para><link xlink:href="http://www.w3.org/XML/Schema">XML
- Schema</link></para>
- </listitem>
-
- <listitem>
- <para><link
- xlink:href="http://www.relaxng.org">RelaxNG</link></para>
- </listitem>
- </itemizedlist>
+<?xml version="1.0" encoding="UTF-8"?>
+<chapter version="5.0" xml:id="xmlSchema"
+ xmlns="http://docbook.org/ns/docbook"
+ xmlns:xlink="http://www.w3.org/1999/xlink"
+ xmlns:xi="http://www.w3.org/2001/XInclude"
+ xmlns:svg="http://www.w3.org/2000/svg"
+ xmlns:m="http://www.w3.org/1998/Math/MathML"
+ xmlns:html="http://www.w3.org/1999/xhtml"
+ xmlns:db="http://docbook.org/ns/docbook">
+ <title>Beyond well- formedness</title>
+
+ <section xml:id="motivationSchema">
+ <title>Motivation</title>
+
+ <para>So far we are able to create XML documents containing hierarchically
+ structured data. We may nest elements and thus create tree structures of
+ arbitrary depth. The only restrictions being imposed by the XML standard
+ are the constraints of well - formedness. For many purposes in software
+ development this is not sufficient.</para>
+
+ <para>A company named <productname>Softmail</productname> might implement
+ an email system which uses <link linkend="memoWellAttrib">memo</link>
+ document files as low level data representation serving as a persistence
+ layer. Now a second company named <productname>Hardmail</productname>
+ wants to integrate mails generated by
+ <productname>Softmail</productname>'s system into its own business
+ product. The <productname>Hardmail</productname> software developers might
+ <emphasis>infer</emphasis> the logical structure of
+ <productname>Softmail</productname>'s email representation but the
+ following problems arise:</para>
+
+ <itemizedlist>
+ <listitem>
+ <para>The logical structure will in practice become more complex:
+ E-mails may contain attachments leading to multi part messages.
+ Additional header information is required for standard Internet mail
+ compliance. This adds additional complexity to the XML structure being
+ mandatory for data representation. Relying only on well-formedness the
+ specification of an internal E-mail format can only be achieved
+ <emphasis>informally</emphasis>. Thus a rule like <quote>Each E-mail
+ must have a subject</quote> may be written down in the specification.
+ A software developer will code these rules but probably make mistakes
+ as the set of rules grows.</para>
+
+ <para>In contrast a RDBMS based solution offers to solve such problems
+ in a declarative manner: A developer may use a <code>NOT NULL</code>
+ constraint on a subject attribute of type <code>VARCHAR</code> thus
+ inhibiting empty subjects.</para>
+ </listitem>
+
+ <listitem>
+ <para>As <productname>Softmail</productname>'s product evolves its
+ internal E-mail XML format is subject to change due to functional
+ extensions and possibly bug fixes both giving rise to interoperability
+ problems.</para>
+ </listitem>
+ </itemizedlist>
+
+ <para>Generally speaking well formed XML documents lack grammar
+ constraints as being available for programming languages. In case of RDBMS
+ developers can impose primary-, foreign and <code>CHECK</code> constraints
+ in a <emphasis>declarative</emphasis> manner rather than hard coding them
+ into their applications (A solution bad programmers are in favour of
+ though...). Various XML standards exist for declarative constraint
+ definitions namely:</para>
+
+ <itemizedlist>
+ <listitem>
+ <para>DTDs</para>
+ </listitem>
+
+ <listitem>
+ <para><link xlink:href="http://www.w3.org/XML/Schema">XML
+ Schema</link></para>
+ </listitem>
+
+ <listitem>
+ <para><link xlink:href="http://www.relaxng.org">RelaxNG</link></para>
+ </listitem>
+ </itemizedlist>
+ </section>
+
+ <section xml:id="dtdBasic">
+ <title>XML Schema</title>
+
+ <section xml:id="dtdFirstExample">
+ <title>Structural descriptions for documents</title>
+
+ <para>As an example we choose documents of type
+ <emphasis>memo</emphasis> as a starting point. Documents like the
+ example from <xref linkend="memoWellAttrib"/> may be
+ <emphasis>informally</emphasis> described to be a sequence of the
+ following mandatory items:</para>
+
+ <figure xml:id="figure_memo_informalconstraints">
+ <title>Informal constraints on <tag class="element">memo</tag>
+ document instances</title>
+
+ <itemizedlist>
+ <listitem>
+ <para><emphasis>Exactly one</emphasis> sender.</para>
+ </listitem>
+
+ <listitem>
+ <para><emphasis>One or more</emphasis> recipients.</para>
+ </listitem>
+
+ <listitem>
+ <para>Subject</para>
+ </listitem>
+
+ <listitem>
+ <para>Content</para>
+ </listitem>
+ </itemizedlist>
+
+ <para>In addition we have:</para>
+
+ <itemizedlist>
+ <listitem>
+ <para>A date string <emphasis>must</emphasis> be supplied</para>
+ </listitem>
+
+ <listitem>
+ <para>A priority <emphasis>may</emphasis> be supplied with allowed
+ values to be chosen from the set of values <tag
+ class="attvalue">low</tag>, <tag class="attvalue">medium</tag> or
+ <tag class="attvalue">high</tag>.</para>
+ </listitem>
+ </itemizedlist>
+ </figure>
+
+ <para>All these fields contain ordinary text to be filled in by a user
+ and shall appear exactly in the defined order. For simplicity we do not
+ care about email address syntax rules being described in <link
+ xlink:href="http://www.w3.org/Protocols/rfc822">RFC based address
+ schemes</link>. We will see how the <emphasis>constraints</emphasis>
+ mentioned above can be modelled in XML by an extension to the concept of
+ well formed documents.</para>
</section>
- <section xml:id="dtdBasic">
- <title>XML Schema</title>
-
- <section xml:id="dtdFirstExample">
- <title>Structural descriptions for documents</title>
-
- <para>As an example we choose documents of type
- <emphasis>memo</emphasis> as a starting point. Documents like the
- example from <xref linkend="memoWellAttrib"/> may be
- <emphasis>informally</emphasis> described to be a sequence of the
- following mandatory items:</para>
-
- <figure xml:id="figure_memo_informalconstraints">
- <title>Informal constraints on <tag class="element">memo</tag>
- document instances</title>
-
- <itemizedlist>
- <listitem>
- <para><emphasis>Exactly one</emphasis> sender.</para>
- </listitem>
-
- <listitem>
- <para><emphasis>One or more</emphasis> recipients.</para>
- </listitem>
-
- <listitem>
- <para>Subject</para>
- </listitem>
-
- <listitem>
- <para>Content</para>
- </listitem>
- </itemizedlist>
-
- <para>In addition we have:</para>
-
- <itemizedlist>
- <listitem>
- <para>A date string <emphasis>must</emphasis> be supplied</para>
- </listitem>
-
- <listitem>
- <para>A priority <emphasis>may</emphasis> be supplied with
- allowed values to be chosen from the set of values <tag
- class="attvalue">low</tag>, <tag class="attvalue">medium</tag>
- or <tag class="attvalue">high</tag>.</para>
- </listitem>
- </itemizedlist>
- </figure>
-
- <para>All these fields contain ordinary text to be filled in by a user
- and shall appear exactly in the defined order. For simplicity we do
- not care about email address syntax rules being described in <link
- xlink:href="http://www.w3.org/Protocols/rfc822">RFC based address
- schemes</link>. We will see how the <emphasis>constraints</emphasis>
- mentioned above can be modelled in XML by an extension to the concept
- of well formed documents.</para>
- </section>
-
- <section xml:id="section_memo_machinereadable">
- <title>A machine readable description</title>
+ <section xml:id="section_memo_machinereadable">
+ <title>A machine readable description</title>
- <para>We now introduce an example of an XML schema. It allows for the
- specification of additional constraints to both element nodes and
- their attributes. Our set of <link
- linkend="figure_memo_informalconstraints" revision="">informal
- constraints</link> on memo documents may be expressed as:</para>
+ <para>We now introduce an example of an XML schema. It allows for the
+ specification of additional constraints to both element nodes and their
+ attributes. Our set of <link linkend="figure_memo_informalconstraints"
+ revision="">informal constraints</link> on memo documents may be
+ expressed as:</para>
- <figure xml:id="figure_memo_dtd">
- <title>A schema to describe memo documents.</title>
+ <figure xml:id="figure_memo_dtd">
+ <title>A schema to describe memo documents.</title>
- <programlisting language="none"><xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
+ <programlisting language="none"><xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:vc="http://www.w3.org/2007/XMLSchema-versioning" elementFormDefault="qualified"
vc:minVersion="1.0" vc:maxVersion="1.1">
@@ -160,13 +159,13 @@
<xs:complexType>
<xs:sequence> <co xml:id="memodtd_memodef"/>
<xs:element name="from" type="xs:string"/> <co
- xml:id="memodtd_elem_from"/>
+ xml:id="memodtd_elem_from"/>
<xs:element name="to" minOccurs="1" maxOccurs="unbounded" type="xs:string"/>
<xs:element name="subject" type="xs:string"/>
<xs:element name="content" type="xs:string"/>
</xs:sequence>
<xs:attribute name="date" type="xs:date" use="required"/> <co
- xml:id="memodtd_memo_attribs"/>
+ xml:id="memodtd_memo_attribs"/>
<xs:attribute name="priority" type="Priority" use="optional"/>
</xs:complexType>
@@ -182,138 +181,148 @@
</xs:schema></programlisting>
- <calloutlist>
- <callout arearefs="memodtd_memodef">
- <para>A <tag class="element">memo</tag> consists of a sender, at
- least one recipient, a subject and content.</para>
- </callout>
-
- <callout arearefs="memodtd_memo_attribs">
- <para>A <tag class="element">memo</tag> has got one required
- attribute <varname>date</varname> and an optional attribute
- <varname>priority</varname> being restricted to the three
- allowed values <tag class="attvalue">low</tag>, <tag
- class="attvalue">medium</tag> and <tag
- class="attvalue">high</tag> being defined by a separate <tag
- class="starttag">xs:simpleType</tag> directive.</para>
- </callout>
-
- <callout arearefs="memodtd_elem_from">
- <para>A <tag class="starttag">from</tag> element consists of
- ordinary text. This disallows XML markup. For example
- <code><from>Smith & partner</from></code> is
- disallowed since XML uses the ampersand (&) to denote the
- beginning of an entity like <tag class="genentity">auml</tag>
- for the German a-umlaut (ä). The correct form is
- <code><from>Smith &amp; partner</from></code>
- using the predefined entity <tag class="genentity">amp</tag> as
- an escape sequence for the ampersand.</para>
-
- <para><code>type="xs:string"</code> is a built in XML Schema
- type representing a restricted version of ordinary strings.
- Without digging into details a <code>xs:string</code> string
- must not contain any markup code like e.g. <tag
- class="starttag">msqrt</tag>. This ensures that a string does
- not interfere with the document's XML markup.</para>
- </callout>
- </calloutlist>
- </figure>
-
- <para>We notice our schema's syntax itself is an XML document.</para>
-
- <para>From the viewpoint of software modeling an XML Schema instance
- is a <emphasis>schema</emphasis> describing the syntax of a class of
- XML document instances adhering to it. In the context of XML
- technologies <link xlink:href="http://www.w3.org/XML/Schema">XML
- Schema</link> is one of several language alternatives which allow for
- XML document structure descriptions.</para>
-
- <para>Readers being familiar with <abbrev
- xlink:href="http://en.wikipedia.org/wiki/Backus-Naur_form">BNF</abbrev>
- or <abbrev
- xlink:href="http://en.wikipedia.org/wiki/Extended_Backus_Naur_form">EBNF</abbrev>
- will be able to understand the grammatical rules being expressed
- here.</para>
-
- <productionset>
- <title>A message of type <tag class="starttag">memo</tag></title>
-
- <production xml:id="memo.ebnf.memo">
- <lhs>Memo Message</lhs>
-
- <rhs>'<memo>' <nonterminal
- def="#memo.ebnf.sender">Sender</nonterminal> [<nonterminal
- def="#memo.ebnf.recipient">Recipient</nonterminal>]+ <nonterminal
- def="#memo.ebnf.subject">Subject</nonterminal> <nonterminal
- def="#memo.ebnf.content">Content</nonterminal>
- '</memo>'</rhs>
- </production>
-
- <production xml:id="memo.ebnf.sender">
- <lhs>Sender</lhs>
-
- <rhs>'<from>' <nonterminal def="#memo.ebnf.text"> Text
- </nonterminal> '</from>'</rhs>
- </production>
-
- <production xml:id="memo.ebnf.recipient">
- <lhs>Recipient</lhs>
-
- <rhs>'<to>' <nonterminal def="#memo.ebnf.text"> Text
- </nonterminal> '</to>'</rhs>
- </production>
-
- <production xml:id="memo.ebnf.subject">
- <lhs>Subject</lhs>
-
- <rhs>'<subject>' <nonterminal def="#memo.ebnf.text"> Text
- </nonterminal> '</subject>'</rhs>
- </production>
-
- <production xml:id="memo.ebnf.content">
- <lhs>Content</lhs>
-
- <rhs>'<content>' <nonterminal def="#memo.ebnf.text"> Text
- </nonterminal> '</content>'</rhs>
- </production>
-
- <production xml:id="memo.ebnf.text">
- <lhs>Text</lhs>
-
- <rhs>[a-zA-Z0-9]* <lineannotation>In real documents this is too
- restrictive!</lineannotation></rhs>
- </production>
- </productionset>
-
- <para>We may as well supply a graphical representation:</para>
-
- <figure xml:id="extendContModelGraph">
- <title>Graphical representation of the extended <code>content</code>
- model.</title>
-
- <mediaobject>
- <imageobject>
- <imagedata fileref="Ref/Fig/contentmixed.fig"/>
- </imageobject>
- </mediaobject>
- </figure>
-
- <para>In comparison to our informal description of memo documents a
- schema offers an added value: The grammar is machine readable and may
- thus become input to a parser which in turn gets enabled to check
- whether an XML document obeys the constraints being imposed. So the
- parser must be instructed to use a schema in addition to the XML
- document in question. For this purpose an XML document may define a
- reference to a schema:</para>
-
- <figure xml:id="memo_external_dtd">
- <title>A memo document instance holding a reference to a document
- external schema.</title>
-
- <programlisting language="none"><memo <co
- xml:id="memo_external_dtd_top_element"/> xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+ <calloutlist>
+ <callout arearefs="memodtd_memodef">
+ <para>A <tag class="element">memo</tag> consists of a sender, at
+ least one recipient, a subject and content.</para>
+ </callout>
+
+ <callout arearefs="memodtd_memo_attribs">
+ <para>A <tag class="element">memo</tag> has got one required
+ attribute <varname>date</varname> and an optional attribute
+ <varname>priority</varname> being restricted to the three allowed
+ values <tag class="attvalue">low</tag>, <tag
+ class="attvalue">medium</tag> and <tag class="attvalue">high</tag>
+ being defined by a separate <tag
+ class="starttag">xs:simpleType</tag> directive. Consider a similar
+ example being inspired from Xhtml:</para>
+
+ <figure xml:id="sda1FigSchemaAttribDef">
+ <title>Attribute schema definition example</title>
+
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="Ref/Fig/attribInElement.fig"/>
+ </imageobject>
+ </mediaobject>
+ </figure>
+ </callout>
+
+ <callout arearefs="memodtd_elem_from">
+ <para>A <tag class="starttag">from</tag> element consists of
+ ordinary text. This disallows XML markup. For example the
+ <quote>&</quote> within <code><from>Smith &
+ partner</from></code> is disallowed since XML uses the
+ ampersand to denote the beginning of an entity like <tag
+ class="genentity">auml</tag> for the German a-umlaut (ä). The
+ correct form is <code><from>Smith &amp;
+ partner</from></code> using the predefined entity <tag
+ class="genentity">amp</tag> as an escape sequence.</para>
+
+ <para><code>type="xs:string"</code> is a built in XML Schema type
+ representing a restricted version of ordinary strings. Without
+ digging into details a <code>xs:string</code> string must not
+ contain any markup code like e.g. <tag
+ class="starttag">msqrt</tag>. This ensures that a string does not
+ interfere with the document's XML markup.</para>
+ </callout>
+ </calloutlist>
+ </figure>
+
+ <para>We notice our schema's syntax itself is an XML document.</para>
+
+ <para>From the viewpoint of software modeling an XML Schema instance is
+ a <emphasis>schema</emphasis> describing the syntax of a class of XML
+ document instances adhering to it. In the context of XML technologies
+ <link xlink:href="http://www.w3.org/XML/Schema">XML Schema</link> is one
+ of several language alternatives which allow for XML document structure
+ descriptions.</para>
+
+ <para>Readers being familiar with <abbrev
+ xlink:href="http://en.wikipedia.org/wiki/Backus-Naur_form">BNF</abbrev>
+ or <abbrev
+ xlink:href="http://en.wikipedia.org/wiki/Extended_Backus_Naur_form">EBNF</abbrev>
+ will be able to understand the grammatical rules being expressed
+ here.</para>
+
+ <productionset>
+ <title>A message of type <tag class="starttag">memo</tag></title>
+
+ <production xml:id="memo.ebnf.memo">
+ <lhs>Memo Message</lhs>
+
+ <rhs>'<memo>' <nonterminal
+ def="#memo.ebnf.sender">Sender</nonterminal> [<nonterminal
+ def="#memo.ebnf.recipient">Recipient</nonterminal>]+ <nonterminal
+ def="#memo.ebnf.subject">Subject</nonterminal> <nonterminal
+ def="#memo.ebnf.content">Content</nonterminal> '</memo>'</rhs>
+ </production>
+
+ <production xml:id="memo.ebnf.sender">
+ <lhs>Sender</lhs>
+
+ <rhs>'<from>' <nonterminal def="#memo.ebnf.text"> Text
+ </nonterminal> '</from>'</rhs>
+ </production>
+
+ <production xml:id="memo.ebnf.recipient">
+ <lhs>Recipient</lhs>
+
+ <rhs>'<to>' <nonterminal def="#memo.ebnf.text"> Text
+ </nonterminal> '</to>'</rhs>
+ </production>
+
+ <production xml:id="memo.ebnf.subject">
+ <lhs>Subject</lhs>
+
+ <rhs>'<subject>' <nonterminal def="#memo.ebnf.text"> Text
+ </nonterminal> '</subject>'</rhs>
+ </production>
+
+ <production xml:id="memo.ebnf.content">
+ <lhs>Content</lhs>
+
+ <rhs>'<content>' <nonterminal def="#memo.ebnf.text"> Text
+ </nonterminal> '</content>'</rhs>
+ </production>
+
+ <production xml:id="memo.ebnf.text">
+ <lhs>Text</lhs>
+
+ <rhs>[a-zA-Z0-9]* <lineannotation>In real documents this is too
+ restrictive!</lineannotation></rhs>
+ </production>
+ </productionset>
+
+ <para>We may as well supply a graphical representation:</para>
+
+ <figure xml:id="extendContModelGraph">
+ <title>Graphical representation of the extended <code>content</code>
+ model.</title>
+
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="Ref/Fig/contentmixed.fig"/>
+ </imageobject>
+ </mediaobject>
+ </figure>
+
+ <para>In comparison to our informal description of memo documents a
+ schema offers an added value: The grammar is machine readable and may
+ thus become input to a parser which in turn gets enabled to check
+ whether an XML document obeys the constraints being imposed. So the
+ parser must be instructed to use a schema in addition to the XML
+ document in question. For this purpose an XML document may define a
+ reference to a schema:</para>
+
+ <figure xml:id="memo_external_dtd">
+ <title>A memo document instance holding a reference to a document
+ external schema.</title>
+
+ <programlisting language="none"><memo <co
+ xml:id="memo_external_dtd_top_element"/> xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="memo.xsd" <co
- xml:id="memo_external_dtd_url"/>
+ xml:id="memo_external_dtd_url"/>
date="2014-09-24" priority="high">
<from>M. Goik</from>
<to>B. King</to>
@@ -322,240 +331,237 @@
<content>Hi all, congratulations to your splendid party</content>
</memo></programlisting>
- <calloutlist>
- <callout arearefs="memo_external_dtd_top_element">
- <para>The element <tag class="starttag">memo</tag> is chosen to
- be the top (root) element of the document's tree. It must be
- defined in our schema <filename>memo.xsd</filename>. This is
- really a choice since an XML schema defines a
- <emphasis>set</emphasis> of elements in
- <emphasis>arbitrary</emphasis> order. There is no such rule as
- <quote>define before use</quote>. So an XML schema does not tell
- us which element has to appear on top of a document.</para>
-
- <para>Suppose a given XML schema offers both <tag
- class="starttag">book</tag> and <tag
- class="starttag">report</tag> elements. An XML author writing a
- complex document will choose <tag class="starttag">book</tag> as
- top level element rather than <tag class="starttag">report</tag>
- being more appropriate for a small piece of documentation.
- Consequently it is an XML authors <emphasis>choice</emphasis>
- which of the elements being defined in a schema shall appear as
- <emphasis>the</emphasis> top level element</para>
- </callout>
-
- <callout arearefs="memo_external_dtd_url">
- <para>The address of the schema's rule set. In the given example
- it is just a filename but it may as well be an <link
- xlink:href="http://www.w3.org/Addressing">URL</link> of type
- <abbrev
- xlink:href="http://en.wikipedia.org/wiki/File_Transfer_Protocol">ftp</abbrev>,
- <abbrev xlink:href="http://www.w3.org/Protocols">http</abbrev>
- and so on, see <xref linkend="memoDtdOnFtp"/>.</para>
- </callout>
- </calloutlist>
- </figure>
-
- <para>In presence of a schema parsing a document is actually a two
- step process: First the parser will check the document for well
- -formedness. Then the parser will read the referenced schema
- <filename>memo.xsd</filename> and check the document for the
- additional constraints being defined within.</para>
-
- <para>In the current example both the schema and the XML memo document
- reside as text files in a common file system folder. For general use a
- schema is usually kept at a centralized location. The attribute
- <varname>xsi:noNamespaceSchemaLocation</varname> value is actually a
- <emphasis>U</emphasis><foreignphrase>niform</foreignphrase>
- <emphasis>R</emphasis><foreignphrase>esource</foreignphrase>
- <emphasis>L</emphasis><foreignphrase>ocator</foreignphrase> <link
- xlink:href="http://www.w3.org/Addressing">(URL)</link>. Thus our
- <filename>memo.xsd</filename> may also be supplied as a <abbrev
- xlink:href="http://www.w3.org/Protocols">http</abbrev> or <abbrev
- xlink:href="http://en.wikipedia.org/wiki/File_Transfer_Protocol">ftp</abbrev>
- <link xlink:href="http://www.w3.org/Addressing">URL</link>:</para>
-
- <figure xml:id="memoDtdOnFtp">
- <title>A schema reference to a FTP server.</title>
-
- <programlisting language="none"><?xml version="1.0" encoding="UTF-8"?>
+ <calloutlist>
+ <callout arearefs="memo_external_dtd_top_element">
+ <para>The element <tag class="starttag">memo</tag> is chosen to be
+ the top (root) element of the document's tree. It must be defined
+ in our schema <filename>memo.xsd</filename>. This is really a
+ choice since an XML schema defines a <emphasis>set</emphasis> of
+ elements in <emphasis>arbitrary</emphasis> order. There is no such
+ rule as <quote>define before use</quote>. So an XML schema does
+ not tell us which element has to appear on top of a
+ document.</para>
+
+ <para>Suppose a given XML schema offers both <tag
+ class="starttag">book</tag> and <tag class="starttag">report</tag>
+ elements. An XML author writing a complex document will choose
+ <tag class="starttag">book</tag> as top level element rather than
+ <tag class="starttag">report</tag> being more appropriate for a
+ small piece of documentation. Consequently it is an XML authors
+ <emphasis>choice</emphasis> which of the elements being defined in
+ a schema shall appear as <emphasis>the</emphasis> top level
+ element</para>
+ </callout>
+
+ <callout arearefs="memo_external_dtd_url">
+ <para>The address of the schema's rule set. In the given example
+ it is just a filename but it may as well be an <link
+ xlink:href="http://www.w3.org/Addressing">URL</link> of type
+ <abbrev
+ xlink:href="http://en.wikipedia.org/wiki/File_Transfer_Protocol">ftp</abbrev>,
+ <abbrev xlink:href="http://www.w3.org/Protocols">http</abbrev> and
+ so on, see <xref linkend="memoDtdOnFtp"/>.</para>
+ </callout>
+ </calloutlist>
+ </figure>
+
+ <para>In presence of a schema parsing a document is actually a two step
+ process: First the parser will check the document for well -formedness.
+ Then the parser will read the referenced schema
+ <filename>memo.xsd</filename> and check the document for the additional
+ constraints being defined within.</para>
+
+ <para>In the current example both the schema and the XML memo document
+ reside as text files in a common file system folder. For general use a
+ schema is usually kept at a centralized location. The attribute
+ <varname>xsi:noNamespaceSchemaLocation</varname> value is actually a
+ <emphasis>U</emphasis><foreignphrase>niform</foreignphrase>
+ <emphasis>R</emphasis><foreignphrase>esource</foreignphrase>
+ <emphasis>L</emphasis><foreignphrase>ocator</foreignphrase> <link
+ xlink:href="http://www.w3.org/Addressing">(URL)</link>. Thus our
+ <filename>memo.xsd</filename> may also be supplied as a <abbrev
+ xlink:href="http://www.w3.org/Protocols">http</abbrev> or <abbrev
+ xlink:href="http://en.wikipedia.org/wiki/File_Transfer_Protocol">ftp</abbrev>
+ <link xlink:href="http://www.w3.org/Addressing">URL</link>:</para>
+
+ <figure xml:id="memoDtdOnFtp">
+ <title>A schema reference to a FTP server.</title>
+
+ <programlisting language="none"><?xml version="1.0" encoding="UTF-8"?>
<memo ... xsi:noNamespaceSchemaLocation="https://someserver.org/memo.xsd">
<from>M. Goik</from>
...
</memo></programlisting>
- </figure>
-
- <para>Some terms are helpful in the context of schemas:</para>
-
- <variablelist>
- <varlistentry>
- <term>Validating / non-validating:</term>
-
- <listitem>
- <para>A non-validating parser only checks a document for well-
- formedness. If it also checks XML documents for conformance to
- schema it is a <emphasis>validating</emphasis> parser.</para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term>Valid / invalid documents:</term>
-
- <listitem>
- <para>An XML document referencing a schema may either be valid
- or invalid depending on its conformance to the schema in
- question.</para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term>Document instance:</term>
-
- <listitem>
- <para>An XML memo document may conform to the <link
- linkend="figure_memo_dtd">memo schema</link>. In this case we
- call it a <emphasis>document instance</emphasis> of the memo
- schema.</para>
-
- <para>This situation is quite similar as in typed programming
- languages: A <xref linkend="glo_Java"/>
- <code>class</code> declaration is a blueprint for the <xref linkend="glo_Java"/> runtime
- system to construct <xref linkend="glo_Java"/> objects
- in memory. This is done by e.g. a statement<code> String name =
- new String();</code>. The identifier <code>name</code> will hold
- a reference to an <emphasis>instance of class String</emphasis>.
- So in a <xref linkend="glo_Java"/> runtime
- environment a class declaration plays the same role as a schema
- declaration in XML. See also <xref
- linkend="example_memoJavaClass"/>.</para>
- </listitem>
- </varlistentry>
- </variablelist>
-
- <para>For further discussions it is very useful to clearly distinguish
- element definitions in a schema from their
- <emphasis>realizations</emphasis> in a corresponding document
- instance: Our memo schema defines an element <tag
- class="starttag">from</tag> to be of content <type>xs:string</type>.
- According to the schema at least one <tag class="starttag">from</tag>
- clause must appear in a valid (conforming) document instance . If we
- were talking about HTML document instances we would prefer to talk
- about a <tag class="starttag">from</tag> <emphasis>tag</emphasis>
- rather than a <tag class="starttag">from</tag>
- <emphasis>element</emphasis>.</para>
-
- <para>In this document we will use the term <emphasis>element
- type</emphasis> to denote an <code><xs:element ...</code>
- definition in a schema. Thus we will talk about an element type <tag
- class="element">subject</tag> being defined in
- <filename>memo.xsd</filename>.</para>
-
- <para>An element type being defined in a <abbrev
- xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>
- may have document instances as realizations. For example the document
- instance shown in <xref linkend="memo_external_dtd"/> has two
- <emphasis>nodes</emphasis> of element type <tag
- class="element">to</tag>. Thus we say that the document instance
- contains two <emphasis>element nodes</emphasis> of type <tag
- class="element">to</tag>. We will frequently abbreviate this by saying
- the instance contains to <tag class="starttag">from</tag> element
- nodes. And we may even omit the term <emphasis>nodes</emphasis> and
- simply talk about two <tag class="starttag">from</tag> elements. But
- the careful reader should always distinguish between a single type
- <code>foo</code> being defined in a <abbrev
- xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>
- and the possibly empty set of <tag class="starttag">foo</tag> nodes
- appearing in valid document instances.</para>
-
- <para><abbrev
- xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">Schema</abbrev>'s
- appear on top of well-formed XML documents:</para>
-
- <figure xml:id="wellformedandvalid">
- <title>Well-formed and valid documents</title>
-
- <mediaobject>
- <imageobject>
- <imagedata fileref="Ref/Fig/wellformedandvalid.fig" scale="65"/>
- </imageobject>
- </mediaobject>
- </figure>
-
- <qandaset defaultlabel="qanda" xml:id="example_memoTestValid">
- <title>Validation of memo document instances.</title>
-
- <qandadiv>
- <qandaentry>
- <question>
- <para>Copy the two files <link
- xlink:href="Ref/src/Memo.1/message.xml">message.xml</link> and
- <link xlink:href="Ref/src/Memo.1/memo.xsd">memo.xsd</link>
- into your eclipse project. Use the Oxygen XML plug in to check
- if the document is valid. Then subsequently do and undo the
- following changes each time checking the document for
- validity:</para>
-
- <itemizedlist>
- <listitem>
- <para>Omit the <tag class="starttag">from</tag>
- element.</para>
- </listitem>
-
- <listitem>
- <para>Change the order of the two sub elements <tag
- class="starttag">subject</tag> and <tag
- class="starttag">content</tag>.</para>
- </listitem>
-
- <listitem>
- <para>Erase the <varname>date</varname> attribute and its
- value.</para>
- </listitem>
-
- <listitem>
- <para>Erase the <varname>priority</varname> attribute and
- its value.</para>
- </listitem>
- </itemizedlist>
-
- <para>What do you observe?</para>
- </question>
-
- <answer>
- <para>The <tag class="attribute">priority</tag> attribute is
- declared as <code>optional</code> and may thus be omitted.
- Erasing the <tag class="attribute">priority</tag> attribute
- thus leaves the document in a valid state. The remaining three
- edit actions yield an invalid document instance.</para>
- </answer>
- </qandaentry>
-
- <qandaentry xml:id="example_memoJavaClass">
- <question>
- <label>A memo implementation sketch in Java</label>
-
- <para>The aim of this exercise is to clarify the (abstract)
- relation between XML <abbrev
- xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>'s
- and sets of <xref linkend="glo_Java"/>
- classes rather then building a running application. We want to
- model the <link xlink:href="Ref/src/Memo.1/memo.xsd">memo
- schema</link> as a set of <xref linkend="glo_Java"/>
- classes.</para>
- </question>
-
- <answer>
- <para>The XML attributes <tag class="attribute">date</tag> and
- <tag class="attribute">priority</tag> can be mapped as <xref linkend="glo_Java"/>
- attributes. The same applies for the Memo elements <tag
- class="element">from</tag>, <tag class="element">subject</tag>
- and <tag class="element">content</tag> which may be
- implemented as simple Strings or alternatively as separate
- Classes wrapping the String content. The latter method of
- implementation should be preferred if the Memo schema is
- expected to grow in complexity. A simple sketch reads:</para>
-
- <programlisting language="none">import java.util.Date;
+ </figure>
+
+ <para>Some terms are helpful in the context of schemas:</para>
+
+ <variablelist>
+ <varlistentry>
+ <term>Validating / non-validating:</term>
+
+ <listitem>
+ <para>A non-validating parser only checks a document for well-
+ formedness. If it also checks XML documents for conformance to
+ schema it is a <emphasis>validating</emphasis> parser.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Valid / invalid documents:</term>
+
+ <listitem>
+ <para>An XML document referencing a schema may either be valid or
+ invalid depending on its conformance to the schema in
+ question.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Document instance:</term>
+
+ <listitem>
+ <para>An XML memo document may conform to the <link
+ linkend="figure_memo_dtd">memo schema</link>. In this case we call
+ it a <emphasis>document instance</emphasis> of the memo
+ schema.</para>
+
+ <para>This situation is quite similar as in typed programming
+ languages: A <xref linkend="glo_Java"/> <code>class</code>
+ declaration is a blueprint for the <xref linkend="glo_Java"/>
+ runtime system to construct <xref linkend="glo_Java"/> objects in
+ memory. This is done by e.g. a statement<code> String name = new
+ String();</code>. The identifier <code>name</code> will hold a
+ reference to an <emphasis>instance of class String</emphasis>. So
+ in a <xref linkend="glo_Java"/> runtime environment a class
+ declaration plays the same role as a schema declaration in XML.
+ See also <xref linkend="example_memoJavaClass"/>.</para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+
+ <para>For further discussions it is very useful to clearly distinguish
+ element definitions in a schema from their
+ <emphasis>realizations</emphasis> in a corresponding document instance:
+ Our memo schema defines an element <tag class="starttag">from</tag> to
+ be of content <type>xs:string</type>. According to the schema at least
+ one <tag class="starttag">from</tag> clause must appear in a valid
+ (conforming) document instance . If we were talking about HTML document
+ instances we would prefer to talk about a <tag
+ class="starttag">from</tag> <emphasis>tag</emphasis> rather than a <tag
+ class="starttag">from</tag> <emphasis>element</emphasis>.</para>
+
+ <para>In this document we will use the term <emphasis>element
+ type</emphasis> to denote an <code><xs:element ...</code> definition
+ in a schema. Thus we will talk about an element type <tag
+ class="element">subject</tag> being defined in
+ <filename>memo.xsd</filename>.</para>
+
+ <para>An element type being defined in a <abbrev
+ xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>
+ may have document instances as realizations. For example the document
+ instance shown in <xref linkend="memo_external_dtd"/> has two
+ <emphasis>nodes</emphasis> of element type <tag
+ class="element">to</tag>. Thus we say that the document instance
+ contains two <emphasis>element nodes</emphasis> of type <tag
+ class="element">to</tag>. We will frequently abbreviate this by saying
+ the instance contains to <tag class="starttag">from</tag> element nodes.
+ And we may even omit the term <emphasis>nodes</emphasis> and simply talk
+ about two <tag class="starttag">from</tag> elements. But the careful
+ reader should always distinguish between a single type <code>foo</code>
+ being defined in a <abbrev
+ xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>
+ and the possibly empty set of <tag class="starttag">foo</tag> nodes
+ appearing in valid document instances.</para>
+
+ <para><abbrev
+ xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">Schema</abbrev>'s
+ appear on top of well-formed XML documents:</para>
+
+ <figure xml:id="wellformedandvalid">
+ <title>Well-formed and valid documents</title>
+
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="Ref/Fig/wellformedandvalid.fig" scale="65"/>
+ </imageobject>
+ </mediaobject>
+ </figure>
+
+ <qandaset defaultlabel="qanda" xml:id="example_memoTestValid">
+ <title>Validation of memo document instances.</title>
+
+ <qandadiv>
+ <qandaentry>
+ <question>
+ <para>Copy the two files <link
+ xlink:href="Ref/src/Memo.1/message.xml">message.xml</link> and
+ <link xlink:href="Ref/src/Memo.1/memo.xsd">memo.xsd</link> into
+ your eclipse project. Use the Oxygen XML plug in to check if the
+ document is valid. Then subsequently do and undo the following
+ changes each time checking the document for validity:</para>
+
+ <itemizedlist>
+ <listitem>
+ <para>Omit the <tag class="starttag">from</tag>
+ element.</para>
+ </listitem>
+
+ <listitem>
+ <para>Change the order of the two sub elements <tag
+ class="starttag">subject</tag> and <tag
+ class="starttag">content</tag>.</para>
+ </listitem>
+
+ <listitem>
+ <para>Erase the <varname>date</varname> attribute and its
+ value.</para>
+ </listitem>
+
+ <listitem>
+ <para>Erase the <varname>priority</varname> attribute and
+ its value.</para>
+ </listitem>
+ </itemizedlist>
+
+ <para>What do you observe?</para>
+ </question>
+
+ <answer>
+ <para>The <tag class="attribute">priority</tag> attribute is
+ declared as <code>optional</code> and may thus be omitted.
+ Erasing the <tag class="attribute">priority</tag> attribute thus
+ leaves the document in a valid state. The remaining three edit
+ actions yield an invalid document instance.</para>
+ </answer>
+ </qandaentry>
+
+ <qandaentry xml:id="example_memoJavaClass">
+ <question>
+ <label>A memo implementation sketch in Java</label>
+
+ <para>The aim of this exercise is to clarify the (abstract)
+ relation between XML <abbrev
+ xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>'s
+ and sets of <xref linkend="glo_Java"/> classes rather then
+ building a running application. We want to model the <link
+ xlink:href="Ref/src/Memo.1/memo.xsd">memo schema</link> as a set
+ of <xref linkend="glo_Java"/> classes.</para>
+ </question>
+
+ <answer>
+ <para>The XML attributes <tag class="attribute">date</tag> and
+ <tag class="attribute">priority</tag> can be mapped as <xref
+ linkend="glo_Java"/> attributes. The same applies for the Memo
+ elements <tag class="element">from</tag>, <tag
+ class="element">subject</tag> and <tag
+ class="element">content</tag> which may be implemented as simple
+ Strings or alternatively as separate Classes wrapping the String
+ content. The latter method of implementation should be preferred
+ if the Memo schema is expected to grow in complexity. A simple
+ sketch reads:</para>
+
+ <programlisting language="none">import java.util.Date;
import java.util.SortedSet;
public class Memo {
@@ -566,88 +572,92 @@ public class Memo {
// Accessors not yet implemented
}</programlisting>
- <para>The only thing to note here is the implementation of the
- <tag class="element">to</tag> element: We want to be able to
- address a <emphasis>set</emphasis> of recipients. Thus we have
- to disallow duplicates. Note that this is an
- <emphasis>informal</emphasis> constraint not being handled by
- our schema: A Memo document instance <emphasis>may</emphasis>
- have duplicate content in <tag class="starttag">to</tag>
- nodes. This is a weakness of <abbrev
- xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>s:
- We are unable to impose uniqueness constraints on the content
- of partial sets of document nodes.</para>
-
- <para>On the other hand our set of recipients has to be
- ordered: In a XML document instance the order of <tag
- class="starttag">to</tag> nodes is important and has to be
- preserved in a <xref linkend="glo_Java"/>
- representation. Thus we choose an
- <classname>java.util.SortedSet</classname> parametrized with
- String type to fulfill both requirements.</para>
-
- <para>Our schema defines:</para>
-
- <programlisting language="none"><!ATTLIST memo ... priority (low|medium|high) #IMPLIED></programlisting>
-
- <para>Starting from <xref linkend="glo_Java"/> 1.5 we
- may implement this constraint by a type safe enumeration in a
- file <filename>Priority.java</filename>:</para>
-
- <programlisting language="none">public enum Priority{low, standard, high};</programlisting>
- </answer>
- </qandaentry>
- </qandadiv>
- </qandaset>
-
- <para>In the following chapters we will extend the memo document type
- (<code><!DOCTYPE memo ... ></code>) to demonstrate various
- concepts of <abbrev
- xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>'s
- and other XML related standards. In parallel a series of exercises
- deals with building a schema usable to edit books. This schema gets
- extended as our knowledge about XML advances. We start with an initial
- exercise:</para>
-
- <qandaset defaultlabel="qanda" xml:id="example_bookDtd">
- <title>A schema for editing books</title>
-
- <qandadiv>
- <qandaentry>
- <question>
- <para>Write a schema describing book document instances with
- the following features:</para>
-
- <itemizedlist>
- <listitem>
- <para>A book shall have a title to describe the book
- itself.</para>
- </listitem>
-
- <listitem>
- <para>A book shall have at least one but possibly a
- sequence of chapters.</para>
- </listitem>
-
- <listitem>
- <para>Each chapter shall have a title and at least one
- paragraph.</para>
- </listitem>
-
- <listitem>
- <para>The titles and paragraphs shall consist of ordinary
- text.</para>
- </listitem>
- </itemizedlist>
- </question>
-
- <answer>
- <para>A possible schema looks like:</para>
-
- <figure xml:id="figure_book.dtd_v1">
- <title>A first schema version for book documents</title>
+ <para>The only thing to note here is the implementation of the
+ <tag class="element">to</tag> element: We want to be able to
+ address a <emphasis>set</emphasis> of recipients. Thus we have
+ to disallow duplicates. Note that this is an
+ <emphasis>informal</emphasis> constraint not being handled by
+ our schema: A Memo document instance <emphasis>may</emphasis>
+ have duplicate content in <tag class="starttag">to</tag> nodes.
+ This is a weakness of <abbrev
+ xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>s:
+ We are unable to impose uniqueness constraints on the content of
+ partial sets of document nodes.</para>
+
+ <para>On the other hand our set of recipients has to be ordered:
+ In a XML document instance the order of <tag
+ class="starttag">to</tag> nodes is important and has to be
+ preserved in a <xref linkend="glo_Java"/> representation. Thus
+ we choose an <classname>java.util.SortedSet</classname>
+ parametrized with String type to fulfill both
+ requirements.</para>
+
+ <para>Our schema defines:</para>
+
+ <programlisting language="none"><xs:simpleType name="Priority">
+ <xs:restriction base="xs:string">
+ <xs:enumeration value="low"/>
+ <xs:enumeration value="medium"/>
+ <xs:enumeration value="high"/>
+ </xs:restriction>
+ </xs:simpleType></programlisting>
+
+ <para>Starting from <xref linkend="glo_Java"/> 1.5 we may
+ implement this constraint by a type safe enumeration:</para>
+
+ <programlisting language="none">public enum Priority {low, standard, high};</programlisting>
+ </answer>
+ </qandaentry>
+ </qandadiv>
+ </qandaset>
+
+ <para>In the following chapters we will extend the memo document schema
+ to demonstrate various concepts of <abbrev
+ xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>'s
+ and other XML related standards. In parallel a series of exercises deals
+ with building a schema usable to edit books. This schema gets extended
+ as our knowledge about XML advances. We start with an initial
+ exercise:</para>
+
+ <qandaset defaultlabel="qanda" xml:id="example_bookDtd">
+ <title>A schema for editing books</title>
+
+ <qandadiv>
+ <qandaentry>
+ <question>
+ <para>Write a schema describing book document instances with the
+ following features:</para>
+
+ <itemizedlist>
+ <listitem>
+ <para>A book shall have a title to describe the book
+ itself.</para>
+ </listitem>
+
+ <listitem>
+ <para>A book shall have at least one but possibly a sequence
+ of chapters.</para>
+ </listitem>
+
+ <listitem>
+ <para>Each chapter shall have a title and at least one
+ paragraph.</para>
+ </listitem>
+
+ <listitem>
+ <para>The titles and paragraphs shall consist of ordinary
+ text.</para>
+ </listitem>
+ </itemizedlist>
+ </question>
+
+ <answer>
+ <para>A possible schema looks like:</para>
+
+ <figure xml:id="figure_book.dtd_v1">
+ <title>A first schema version for book documents</title>
- <programlisting language="none"><xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
+ <programlisting language="none"><xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:vc="http://www.w3.org/2007/XMLSchema-versioning" elementFormDefault="qualified"
vc:minVersion="1.0" vc:maxVersion="1.1">
@@ -673,12 +683,12 @@ public class Memo {
<xs:element name="para" type="xs:string"/>
</xs:schema></programlisting>
- </figure>
+ </figure>
- <para>We supply a valid document instance:</para>
+ <para>We supply a valid document instance:</para>
- <informalfigure xml:id="bookInitialInstance">
- <programlisting language="none"><?xml version="1.0" encoding="UTF-8"?>
+ <informalfigure xml:id="bookInitialInstance">
+ <programlisting language="none"><?xml version="1.0" encoding="UTF-8"?>
<book xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="book.xsd">
<title>Introduction to Java</title>
@@ -696,67 +706,67 @@ public class Memo {
<para>This is especially useful for framework authors.</para>
</chapter>
</book></programlisting>
- </informalfigure>
-
- <para>.</para>
- </answer>
- </qandaentry>
- </qandadiv>
- </qandaset>
- </section>
-
- <section xml:id="dtdVsSqlDdl">
- <title>Relating <abbrev
- xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>'s
- and <acronym
- xlink:href="http://en.wikipedia.org/wiki/Sql">SQL</acronym> - <abbrev
- xlink:href="http://en.wikipedia.org/wiki/Data_definition_language">DDL</abbrev></title>
+ </informalfigure>
- <para>XML <abbrev
- xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>'s
- and <acronym
- xlink:href="http://en.wikipedia.org/wiki/Sql">SQL</acronym> - <abbrev
- xlink:href="http://en.wikipedia.org/wiki/Data_definition_language">DDL</abbrev>
- are related: They both describe data models and thus integrity
- constraints. We consider a simple invoice example:</para>
-
- <figure xml:id="invoiceIntegrity">
- <title>Invoice integrity constraints</title>
-
- <mediaobject>
- <imageobject>
- <imagedata fileref="Ref/Fig/invoicedata.fig" scale="65"/>
- </imageobject>
- </mediaobject>
- </figure>
-
- <para>A relational implementation may look like:</para>
-
- <figure xml:id="invoiceSqlDdl">
- <title>Relational implementation</title>
-
- <mediaobject>
- <imageobject>
- <imagedata fileref="Ref/Fig/invoicedataimplement.fig" scale="65"/>
- </imageobject>
- </mediaobject>
- </figure>
-
- <qandaset defaultlabel="qanda" xml:id="qandaInvoiceSchema">
- <title>An XML schema representing invoices</title>
-
- <qandadiv>
- <qandaentry>
- <question>
- <para>Represent the relational schema being described in <xref
- linkend="invoiceSqlDdl"/> by an XML Schema and provide an
- appropriate instance example.</para>
- </question>
-
- <answer>
- <para>A possible schema implementation:</para>
+ <para>.</para>
+ </answer>
+ </qandaentry>
+ </qandadiv>
+ </qandaset>
+ </section>
- <programlisting language="none"><xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
+ <section xml:id="dtdVsSqlDdl">
+ <title>Relating <abbrev
+ xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>'s
+ and <acronym xlink:href="http://en.wikipedia.org/wiki/Sql">SQL</acronym>
+ - <abbrev
+ xlink:href="http://en.wikipedia.org/wiki/Data_definition_language">DDL</abbrev></title>
+
+ <para>XML <abbrev
+ xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>'s
+ and <acronym xlink:href="http://en.wikipedia.org/wiki/Sql">SQL</acronym>
+ - <abbrev
+ xlink:href="http://en.wikipedia.org/wiki/Data_definition_language">DDL</abbrev>
+ are related: They both describe data models and thus integrity
+ constraints. We consider a simple invoice example:</para>
+
+ <figure xml:id="invoiceIntegrity">
+ <title>Invoice integrity constraints</title>
+
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="Ref/Fig/invoicedata.fig" scale="65"/>
+ </imageobject>
+ </mediaobject>
+ </figure>
+
+ <para>A relational implementation may look like:</para>
+
+ <figure xml:id="invoiceSqlDdl">
+ <title>Relational implementation</title>
+
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="Ref/Fig/invoicedataimplement.fig" scale="65"/>
+ </imageobject>
+ </mediaobject>
+ </figure>
+
+ <qandaset defaultlabel="qanda" xml:id="qandaInvoiceSchema">
+ <title>An XML schema representing invoices</title>
+
+ <qandadiv>
+ <qandaentry>
+ <question>
+ <para>Represent the relational schema being described in <xref
+ linkend="invoiceSqlDdl"/> by an XML Schema and provide an
+ appropriate instance example.</para>
+ </question>
+
+ <answer>
+ <para>A possible schema implementation:</para>
+
+ <programlisting language="none"><xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:vc="http://www.w3.org/2007/XMLSchema-versioning" elementFormDefault="qualified"
vc:minVersion="1.0" vc:maxVersion="1.1">
@@ -814,9 +824,9 @@ public class Memo {
</xs:schema></programlisting>
- <para>An example data set:</para>
+ <para>An example data set:</para>
- <programlisting language="none"><data xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+ <programlisting language="none"><data xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="invoice.xsd">
<customer id="5">
<name>Clarke Jefferson</name>
@@ -827,68 +837,68 @@ public class Memo {
<status>due</status>
</invoice>
</data></programlisting>
- </answer>
- </qandaentry>
- </qandadiv>
- </qandaset>
- </section>
+ </answer>
+ </qandaentry>
+ </qandadiv>
+ </qandaset>
+ </section>
- <section xml:id="airlineXsd">
- <title>The airline example revisited</title>
+ <section xml:id="airlineXsd">
+ <title>The airline example revisited</title>
- <qandaset defaultlabel="qanda" xml:id="qandaAirlineXsd">
- <title>Airline meta information by XML schema</title>
+ <qandaset defaultlabel="qanda" xml:id="qandaAirlineXsd">
+ <title>Airline meta information by XML schema</title>
- <qandadiv>
- <qandaentry>
- <question>
- <para>Transform the relational schema from <xref
- linkend="airlineRelationalSchema"/> into an XML schema and
- supply some test data. In particular consider the following
- constraints:</para>
+ <qandadiv>
+ <qandaentry>
+ <question>
+ <para>Transform the relational schema from <xref
+ linkend="airlineRelationalSchema"/> into an XML schema and
+ supply some test data. In particular consider the following
+ constraints:</para>
- <itemizedlist>
- <listitem>
- <para>Data types</para>
-
- <itemizedlist>
- <listitem>
- <para><link
- xlink:href="http://en.wikipedia.org/wiki/List_of_airline_codes">ICAO
- airline designator</link></para>
- </listitem>
-
- <listitem>
- <para><link
- xlink:href="http://en.wikipedia.org/wiki/International_Civil_Aviation_Organization_airport_code">ICAO
- airport code</link></para>
- </listitem>
- </itemizedlist>
- </listitem>
+ <itemizedlist>
+ <listitem>
+ <para>Data types</para>
- <listitem>
- <para>Primary / Unique key definitions</para>
- </listitem>
-
- <listitem>
- <para>Foreign key definitions</para>
- </listitem>
-
- <listitem>
- <para>CHECK constraint: Your XML schema will require <tag
- class="starttag">xs:assert test="..." </tag> and thus XML
- schema version 1.1. You may want to read about
- co-occurrence constraints as being described in <link
- xlink:href="http://www.ibm.com/developerworks/library/x-xml11pt2">Listing
- 6. Assertion on complex type - @height <
- @width</link>.</para>
- </listitem>
- </itemizedlist>
-
- <para>The following XML example instance may guide you towards
- an <filename>airline.xsd</filename> schema:</para>
+ <itemizedlist>
+ <listitem>
+ <para><link
+ xlink:href="http://en.wikipedia.org/wiki/List_of_airline_codes">ICAO
+ airline designator</link></para>
+ </listitem>
- <programlisting language="none"><top xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+ <listitem>
+ <para><link
+ xlink:href="http://en.wikipedia.org/wiki/International_Civil_Aviation_Organization_airport_code">ICAO
+ airport code</link></para>
+ </listitem>
+ </itemizedlist>
+ </listitem>
+
+ <listitem>
+ <para>Primary / Unique key definitions</para>
+ </listitem>
+
+ <listitem>
+ <para>Foreign key definitions</para>
+ </listitem>
+
+ <listitem>
+ <para>CHECK constraint: Your XML schema will require <tag
+ class="starttag">xs:assert test="..." </tag> and thus XML
+ schema version 1.1. You may want to read about co-occurrence
+ constraints as being described in <link
+ xlink:href="http://www.ibm.com/developerworks/library/x-xml11pt2">Listing
+ 6. Assertion on complex type - @height <
+ @width</link>.</para>
+ </listitem>
+ </itemizedlist>
+
+ <para>The following XML example instance may guide you towards
+ an <filename>airline.xsd</filename> schema:</para>
+
+ <programlisting language="none"><top xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="airline.xsd">
<airlines>
<airline airlineCode="DLH" id="1">
@@ -915,26 +925,26 @@ public class Memo {
</flights>
</top></programlisting>
- <para>Hints:</para>
-
- <itemizedlist>
- <listitem>
- <para>Identify all relational schema constraints from
- solution of <xref linkend="airlineRelationalSchema"/> and
- model them accordingly.</para>
- </listitem>
-
- <listitem>
- <para>The above example does not contain any constraint
- violations. In order to test your schema for completeness
- tinkering with primary key, unique and referencing
- attribute values may be helpful.</para>
- </listitem>
- </itemizedlist>
- </question>
-
- <answer>
- <programlisting language="none"><xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
+ <para>Hints:</para>
+
+ <itemizedlist>
+ <listitem>
+ <para>Identify all relational schema constraints from
+ solution of <xref linkend="airlineRelationalSchema"/> and
+ model them accordingly.</para>
+ </listitem>
+
+ <listitem>
+ <para>The above example does not contain any constraint
+ violations. In order to test your schema for completeness
+ tinkering with primary key, unique and referencing attribute
+ values may be helpful.</para>
+ </listitem>
+ </itemizedlist>
+ </question>
+
+ <answer>
+ <programlisting language="none"><xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:vc="http://www.w3.org/2007/XMLSchema-versioning" elementFormDefault="qualified"
vc:minVersion="1.1">
@@ -1076,53 +1086,52 @@ public class Memo {
</xs:element>
</xs:schema></programlisting>
- </answer>
- </qandaentry>
- </qandadiv>
- </qandaset>
- </section>
+ </answer>
+ </qandaentry>
+ </qandadiv>
+ </qandaset>
+ </section>
+
+ <section xml:id="xmlAndJava">
+ <title>Relating <abbrev
+ xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>'s
+ and <xref linkend="glo_Java"/> class descriptions.</title>
- <section xml:id="xmlAndJava">
- <title>Relating <abbrev
+ <para>We may also compare XML data constraints to <xref
+ linkend="glo_Java"/>. A <xref linkend="glo_Java"/> class declaration is
+ actually a blueprint for a <trademark
+ xlink:href="http://www.oracle.com/technetwork/java/javase">JRE</trademark>
+ to instantiate compatible objects. Likewise an XML schema restricts
+ well-formed documents:</para>
+
+ <figure xml:id="fig_XmlAndJava">
+ <title>XML <abbrev
xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>'s
- and <xref linkend="glo_Java"/>
- class descriptions.</title>
-
- <para>We may also compare XML data constraints to <xref linkend="glo_Java"/>. A <xref linkend="glo_Java"/> class
- declaration is actually a blueprint for a <trademark
- xlink:href="http://www.oracle.com/technetwork/java/javase">JRE</trademark>
- to instantiate compatible objects. Likewise an XML schema restricts
- well-formed documents:</para>
-
- <figure xml:id="fig_XmlAndJava">
- <title>XML <abbrev
- xlink:href="http://en.wikipedia.org/wiki/Document_Type_Declaration">schema</abbrev>'s
- and <xref linkend="glo_Java"/>
- class declarations.</title>
-
- <mediaobject>
- <imageobject>
- <imagedata fileref="Ref/Fig/xmlattribandjava.fig" scale="65"/>
- </imageobject>
- </mediaobject>
- </figure>
- </section>
+ and <xref linkend="glo_Java"/> class declarations.</title>
+
+ <mediaobject>
+ <imageobject>
+ <imagedata fileref="Ref/Fig/xmlattribandjava.fig" scale="65"/>
+ </imageobject>
+ </mediaobject>
+ </figure>
+ </section>
- <section xml:id="xmlSchemaExercise">
- <title>XML schema exercises</title>
+ <section xml:id="xmlSchemaExercise">
+ <title>XML schema exercises</title>
- <section xml:id="sectSchemaProductCatalog">
- <title>A product catalog</title>
+ <section xml:id="sectSchemaProductCatalog">
+ <title>A product catalog</title>
- <qandaset defaultlabel="qanda" xml:id="quandaProductCatalog">
- <title>Product catalog schema</title>
+ <qandaset defaultlabel="qanda" xml:id="quandaProductCatalog">
+ <title>Product catalog schema</title>
- <qandadiv>
- <qandaentry>
- <question>
- <para>Consider the following product catalog example:</para>
+ <qandadiv>
+ <qandaentry>
+ <question>
+ <para>Consider the following product catalog example:</para>
- <programlisting language="none"><catalog xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+ <programlisting language="none"><catalog xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="catalog.xsd">
<title>Outdoor products</title>
<introduction>
@@ -1146,53 +1155,51 @@ public class Memo {
</product>
</catalog></programlisting>
- <para>As you may have inferred the following rules shall
- apply for arbitrary catalog documents:</para>
+ <para>As you may have inferred the following rules shall apply
+ for arbitrary catalog documents:</para>
- <itemizedlist>
- <listitem>
- <para>Each <tag class="starttag">catalog</tag> shall
- have exactly one <tag class="starttag">title</tag> and
- <tag class="starttag">introduction</tag> element.</para>
- </listitem>
+ <itemizedlist>
+ <listitem>
+ <para>Each <tag class="starttag">catalog</tag> shall have
+ exactly one <tag class="starttag">title</tag> and <tag
+ class="starttag">introduction</tag> element.</para>
+ </listitem>
- <listitem>
- <para><tag class="starttag">introduction</tag> and <tag
- class="starttag">description</tag> shall have at least
- one <tag class="starttag">para</tag> child.</para>
- </listitem>
+ <listitem>
+ <para><tag class="starttag">introduction</tag> and <tag
+ class="starttag">description</tag> shall have at least one
+ <tag class="starttag">para</tag> child.</para>
+ </listitem>
- <listitem>
- <para>Each <tag class="starttag">catalog</tag> shall
- have at least one <tag
- class="starttag">product</tag>.</para>
- </listitem>
+ <listitem>
+ <para>Each <tag class="starttag">catalog</tag> shall have
+ at least one <tag class="starttag">product</tag>.</para>
+ </listitem>
- <listitem>
- <para>Each <tag class="starttag">product</tag> shall
- have exactly one <tag class="starttag">title</tag> and
- at least one <tag class="starttag">para</tag> child
- element.</para>
- </listitem>
+ <listitem>
+ <para>Each <tag class="starttag">product</tag> shall have
+ exactly one <tag class="starttag">title</tag> and at least
+ one <tag class="starttag">para</tag> child element.</para>
+ </listitem>
- <listitem>
- <para>The required <code>id</code> attribute shall not
- contain whitespace and be unique with respect to all
- <tag class="starttag">product</tag> elements.</para>
- </listitem>
+ <listitem>
+ <para>The required <code>id</code> attribute shall not
+ contain whitespace and be unique with respect to all <tag
+ class="starttag">product</tag> elements.</para>
+ </listitem>
- <listitem>
- <para>The attribute price shall represent money amounts
- and be optional.</para>
- </listitem>
- </itemizedlist>
+ <listitem>
+ <para>The attribute price shall represent money amounts
+ and be optional.</para>
+ </listitem>
+ </itemizedlist>
- <para>Provide a suitable <filename>catalog.xsd</filename>
- schema.</para>
- </question>
+ <para>Provide a suitable <filename>catalog.xsd</filename>
+ schema.</para>
+ </question>
- <answer>
- <programlisting language="none"><xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
+ <answer>
+ <programlisting language="none"><xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:vc="http://www.w3.org/2007/XMLSchema-versioning" elementFormDefault="qualified"
vc:minVersion="1.0" vc:maxVersion="1.1">
@@ -1241,56 +1248,55 @@ public class Memo {
</xs:element>
</xs:schema></programlisting>
- </answer>
- </qandaentry>
- </qandadiv>
- </qandaset>
- </section>
-
- <section xml:id="sectQandaBookV1">
- <title>Book like documents</title>
-
- <qandaset defaultlabel="qanda" xml:id="example_operatorprecedence">
- <title>Book documents with mixed content and itemized
- lists</title>
-
- <qandadiv>
- <qandaentry xml:id="example_book_v2">
- <question>
- <para>Extend the first version of <link
- linkend="example_bookDtd">book.xsd</link> to support the
- following features:</para>
+ </answer>
+ </qandaentry>
+ </qandadiv>
+ </qandaset>
+ </section>
- <itemizedlist>
- <listitem>
- <para>Within a <tag class="starttag">chapter</tag> node
- <tag class="starttag">para</tag> and <tag
- class="starttag">itemizedlist</tag> elements in
- arbitrary order shall be allowed.</para>
- </listitem>
+ <section xml:id="sectQandaBookV1">
+ <title>Book like documents</title>
- <listitem>
- <para><tag class="starttag">itemizedlist</tag> nodes
- shall contain at least one <tag
- class="starttag">listitem</tag>.</para>
- </listitem>
+ <qandaset defaultlabel="qanda" xml:id="example_operatorprecedence">
+ <title>Book documents with mixed content and itemized lists</title>
- <listitem>
- <para><tag class="starttag">listitem</tag> nodes shall
- be composed of one or more para or nested list item
- elements.</para>
- </listitem>
+ <qandadiv>
+ <qandaentry xml:id="example_book_v2">
+ <question>
+ <para>Extend the first version of <link
+ linkend="example_bookDtd">book.xsd</link> to support the
+ following features:</para>
- <listitem>
- <para>Within a <tag class="starttag">para</tag> we want
- to be able to emphasize text passages.</para>
- </listitem>
- </itemizedlist>
+ <itemizedlist>
+ <listitem>
+ <para>Within a <tag class="starttag">chapter</tag> node
+ <tag class="starttag">para</tag> and <tag
+ class="starttag">itemizedlist</tag> elements in arbitrary
+ order shall be allowed.</para>
+ </listitem>
+
+ <listitem>
+ <para><tag class="starttag">itemizedlist</tag> nodes shall
+ contain at least one <tag
+ class="starttag">listitem</tag>.</para>
+ </listitem>
- <para>The following sample document instance shall be
- valid:</para>
+ <listitem>
+ <para><tag class="starttag">listitem</tag> nodes shall be
+ composed of one or more para or nested list item
+ elements.</para>
+ </listitem>
- <programlisting language="none"><?xml version="1.0" encoding="UTF-8"?>
+ <listitem>
+ <para>Within a <tag class="starttag">para</tag> we want to
+ be able to emphasize text passages.</para>
+ </listitem>
+ </itemizedlist>
+
+ <para>The following sample document instance shall be
+ valid:</para>
+
+ <programlisting language="none"><?xml version="1.0" encoding="UTF-8"?>
<book xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="catalog.xsd">
<title>Introduction to Java</title>
@@ -1311,15 +1317,15 @@ public class Memo {
</itemizedlist>
</chapter>
</book></programlisting>
- </question>
+ </question>
- <answer>
- <para>An extended schema looks like:</para>
+ <answer>
+ <para>An extended schema looks like:</para>
- <figure xml:id="paraListEmphasize">
- <title>Version 2 of book.xsd</title>
+ <figure xml:id="paraListEmphasize">
+ <title>Version 2 of book.xsd</title>
- <programlisting language="none"><?xml version="1.0" encoding="UTF-8"?>
+ <programlisting language="none"><?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:vc="http://www.w3.org/2007/XMLSchema-versioning" elementFormDefault="qualified"
vc:minVersion="1.0" vc:maxVersion="1.1">
@@ -1378,7 +1384,7 @@ public class Memo {
<xs:element name="para">
<xs:complexType mixed="true"> <co
- xml:id="figure_book.dtd_v2_para"/>
+ xml:id="figure_book.dtd_v2_para"/>
<xs:choice minOccurs="0" maxOccurs="unbounded">
<xs:element ref="emphasis"/>
<xs:element ref="link"/>
@@ -1391,7 +1397,7 @@ public class Memo {
<xs:complexType>
<xs:sequence>
<xs:element ref="listitem" minOccurs="1" <co
- xml:id="figure_book.dtd_v2_itemizedlist"/> maxOccurs="unbounded"/>
+ xml:id="figure_book.dtd_v2_itemizedlist"/> maxOccurs="unbounded"/>
</xs:sequence>
<xs:attribute name="id" type="xs:ID" use="optional"/>
</xs:complexType>
@@ -1400,7 +1406,7 @@ public class Memo {
<xs:element name="listitem">
<xs:complexType>
<xs:choice minOccurs="1" maxOccurs="unbounded"> <co
- xml:id="figure_book.dtd_v2_listitem"/>
+ xml:id="figure_book.dtd_v2_listitem"/>
<xs:element ref="para"/>
<xs:element ref="itemizedlist"/>
</xs:choice>
@@ -1409,97 +1415,95 @@ public class Memo {
</xs:schema></programlisting>
- <caption>
- <para>This allows emphasized text in <tag
- class="starttag">para</tag> nodes and <tag
- class="starttag">itemizedlists</tag>.</para>
- </caption>
- </figure>
-
- <calloutlist>
- <callout arearefs="figure_book.dtd_v2_chapter">
- <para>We hook into <tag class="starttag">chapter</tag>
- to allow arbitrary sequences of at least one <tag
- class="starttag">para</tag> or <tag
- class="starttag">itemizedlist</tag> element node.</para>
- </callout>
-
- <callout arearefs="figure_book.dtd_v2_para">
- <para><tag class="starttag">para</tag> nodes now allow
- mixed content.</para>
- </callout>
-
- <callout arearefs="figure_book.dtd_v2_itemizedlist">
- <para>An <tag class="starttag">itemizedlist</tag>
- contains at least one list item.</para>
- </callout>
-
- <callout arearefs="figure_book.dtd_v2_listitem">
- <para>A <tag class="starttag">listitem</tag> contains a
- sequence of at least one <tag
- class="starttag">para</tag> or <tag
- class="starttag">itemizedlist</tag> child node. The
- latter gives rise to nested lists. We find a similar
- construct in HTML namely unnumbered lists defined by
- <code><UL><LI>... </code>constructs.</para>
- </callout>
- </calloutlist>
- </answer>
- </qandaentry>
- </qandadiv>
- </qandaset>
- </section>
-
- <section xml:id="sectQandaBookLang">
- <title>Allow different languages</title>
-
- <qandaset defaultlabel="qanda" xml:id="example_book.dtd_v3">
- <title>book.xsd and languages</title>
-
- <qandadiv>
- <qandaentry>
- <question>
- <para>We want to extend our schema from <xref
- linkend="example_book_v2"/> by allowing an author to define
- the language to be used within the whole or parts of the
- document in question. Add an attribute <code>lang</code> to
- all relevant elements like e.g. <tag class="starttag">para
- lang="es"</tag>. An XML editor may use this attribute to
- activate corresponding dictionaries for spell
- checking.</para>
-
- <para>The <code>lang</code> attribute shall be restricted to
- the following values:</para>
+ <caption>
+ <para>This allows emphasized text in <tag
+ class="starttag">para</tag> nodes and <tag
+ class="starttag">itemizedlists</tag>.</para>
+ </caption>
+ </figure>
- <itemizedlist>
- <listitem>
- <para><token>en</token></para>
- </listitem>
+ <calloutlist>
+ <callout arearefs="figure_book.dtd_v2_chapter">
+ <para>We hook into <tag class="starttag">chapter</tag> to
+ allow arbitrary sequences of at least one <tag
+ class="starttag">para</tag> or <tag
+ class="starttag">itemizedlist</tag> element node.</para>
+ </callout>
+
+ <callout arearefs="figure_book.dtd_v2_para">
+ <para><tag class="starttag">para</tag> nodes now allow
+ mixed content.</para>
+ </callout>
+
+ <callout arearefs="figure_book.dtd_v2_itemizedlist">
+ <para>An <tag class="starttag">itemizedlist</tag> contains
+ at least one list item.</para>
+ </callout>
+
+ <callout arearefs="figure_book.dtd_v2_listitem">
+ <para>A <tag class="starttag">listitem</tag> contains a
+ sequence of at least one <tag class="starttag">para</tag>
+ or <tag class="starttag">itemizedlist</tag> child node.
+ The latter gives rise to nested lists. We find a similar
+ construct in HTML namely unnumbered lists defined by
+ <code><UL><LI>... </code>constructs.</para>
+ </callout>
+ </calloutlist>
+ </answer>
+ </qandaentry>
+ </qandadiv>
+ </qandaset>
+ </section>
- <listitem>
- <para><token>fr</token></para>
- </listitem>
+ <section xml:id="sectQandaBookLang">
+ <title>Allow different languages</title>
- <listitem>
- <para><token>de</token></para>
- </listitem>
+ <qandaset defaultlabel="qanda" xml:id="example_book.dtd_v3">
+ <title>book.xsd and languages</title>
- <listitem>
- <para><token>it</token></para>
- </listitem>
+ <qandadiv>
+ <qandaentry>
+ <question>
+ <para>We want to extend our schema from <xref
+ linkend="example_book_v2"/> by allowing an author to define
+ the language to be used within the whole or parts of the
+ document in question. Add an attribute <code>lang</code> to
+ all relevant elements like e.g. <tag class="starttag">para
+ lang="es"</tag>. An XML editor may use this attribute to
+ activate corresponding dictionaries for spell checking.</para>
- <listitem>
- <para><token>es</token></para>
- </listitem>
- </itemizedlist>
- </question>
+ <para>The <code>lang</code> attribute shall be restricted to
+ the following values:</para>
+
+ <itemizedlist>
+ <listitem>
+ <para><token>en</token></para>
+ </listitem>
+
+ <listitem>
+ <para><token>fr</token></para>
+ </listitem>
+
+ <listitem>
+ <para><token>de</token></para>
+ </listitem>
+
+ <listitem>
+ <para><token>it</token></para>
+ </listitem>
+
+ <listitem>
+ <para><token>es</token></para>
+ </listitem>
+ </itemizedlist>
+ </question>
- <answer>
- <para>We define a suitable <tag
- class="starttag">xs:attribute</tag> type:</para>
+ <answer>
+ <para>We define a suitable <tag
+ class="starttag">xs:attribute</tag> type:</para>
- <programlisting language="none"><xs:attribute <emphasis
- role="bold">name="lang"</emphasis>>
+ <programlisting language="none"><xs:attribute <emphasis
+ role="bold">name="lang"</emphasis>>
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:enumeration value="en"/>
@@ -1511,10 +1515,10 @@ public class Memo {
</xs:simpleType>
</xs:attribute></programlisting>
- <para>Than we add this attribute to our elements like <tag
- class="starttag">chapter</tag> and others:</para>
+ <para>Than we add this attribute to our elements like <tag
+ class="starttag">chapter</tag> and others:</para>
- <programlisting language="none"> <xs:element name="chapter">
+ <programlisting language="none"> <xs:element name="chapter">
<xs:complexType>
<xs:sequence> ... </xs:sequence>
<xs:attribute <emphasis role="bold">ref="lang"</emphasis> use="optional"/>
@@ -1522,177 +1526,176 @@ public class Memo {
</xs:complexType>
</xs:element></programlisting>
- <para>This allows us to set a language on arbitrary
- hierarchy level. But of course we may define it on top level
- as well:</para>
+ <para>This allows us to set a language on arbitrary hierarchy
+ level. But of course we may define it on top level as
+ well:</para>
- <programlisting language="none"><?xml version="1.0" encoding="UTF-8"?>
+ <programlisting language="none"><?xml version="1.0" encoding="UTF-8"?>
<book ... lang="english">
<title>Introduction to Java</title>
...</programlisting>
- </answer>
- </qandaentry>
- </qandadiv>
- </qandaset>
- </section>
-
- <section xml:id="sectMixQuotes">
- <title>Mixing attribute quotes</title>
-
- <qandaset defaultlabel="qanda" xml:id="example_quotes">
- <title>Single and double quotes reconsidered</title>
-
- <qandadiv>
- <qandaentry>
- <question>
- <para>We recall the problem of nested quotes yielding
- non-well formed XML code:</para>
-
- <programlisting language="none"><img src="bold.gif" alt="We may use "quotes" here" /></programlisting>
-
- <para>The XML specification defines legal attribute value
- definitions as:</para>
-
- <productionset>
- <title><link
- xlink:href="http://www.w3.org/TR/2008/REC-xml-20081126/#d0e888">Literals</link></title>
-
- <production xml:id="w3RecXml_NT-EntityValue">
- <lhs>EntityValue</lhs>
-
- <rhs>'"' ([^%&"] | <nonterminal
- def="#w3RecXml_NT-PEReference">PEReference</nonterminal>
- | <nonterminal
- def="#w3RecXml_NT-Reference">Reference</nonterminal>)*
- '"' |Â "'" ([^%&'] | <nonterminal
- def="#w3RecXml_NT-PEReference">PEReference</nonterminal>
- | <nonterminal
- def="#w3RecXml_NT-Reference">Reference</nonterminal>)*
- "'"</rhs>
- </production>
-
- <production xml:id="w3RecXml_NT-AttValue">
- <lhs>AttValue</lhs>
-
- <rhs>'"' ([^<&"] | <nonterminal
- def="#w3RecXml_NT-Reference">Reference</nonterminal>)*
- '"' |Â "'" ([^<&'] | <nonterminal
- def="#w3RecXml_NT-Reference">Reference</nonterminal>)*
- "'"</rhs>
- </production>
-
- <production xml:id="w3RecXml_NT-SystemLiteral">
- <lhs>SystemLiteral</lhs>
-
- <rhs>('"' [^"]* '"') |Â ("'" [^']* "'")</rhs>
- </production>
-
- <production xml:id="w3RecXml_NT-PubidLiteral">
- <lhs>PubidLiteral</lhs>
-
- <rhs>'"' <nonterminal
- def="#w3RecXml_NT-PubidChar">PubidChar</nonterminal>*
- '"' | "'" (<nonterminal
- def="#w3RecXml_NT-PubidChar">PubidChar</nonterminal> -
- "'")* "'"</rhs>
- </production>
-
- <production xml:id="w3RecXml_NT-PubidChar">
- <lhs>PubidChar</lhs>
-
- <rhs>#x20 | #xD | #xA |Â [a-zA-Z0-9]
- |Â [-'()+,./:=?;!*#@$_%]</rhs>
- </production>
- </productionset>
-
- <para>Find out how it is possible to set the attribute <tag
- class="attribute">alt</tag>'s value to the string <code>We
- may use "quotes" here</code>.</para>
- </question>
-
- <answer>
- <para>The production rule for attribute values reads:</para>
-
- <productionset>
- <productionrecap linkend="w3RecXml_NT-AttValue"/>
- </productionset>
-
- <para>This allows us to use either of two alternatives to
- delimit attribute values:</para>
-
- <glosslist>
- <glossentry>
- <glossterm><tag class="starttag">img ...
- alt="..."/</tag></glossterm>
-
- <glossdef>
- <para><emphasis>Validity constraint:</emphasis> do not
- use <code>"</code> inside the value string.</para>
- </glossdef>
- </glossentry>
-
- <glossentry>
- <glossterm><tag class="starttag">img ...
- alt='...'/</tag></glossterm>
-
- <glossdef>
- <para><emphasis>Validity constraint:</emphasis> do not
- use <code>'</code> inside the value string.</para>
- </glossdef>
- </glossentry>
- </glosslist>
-
- <para>We may take advantage of the second rule:</para>
-
- <programlisting language="none"><img src="bold.gif" alt='We may use "quotes" here' /></programlisting>
-
- <para>Notice that according to <xref
- linkend="w3RecXml_NT-AttValue"/> the delimiting quotes must
- not be mixed. The following code is thus not well
- formed:</para>
-
- <programlisting language="none"><img src="bold.gif'/></programlisting>
- </answer>
- </qandaentry>
- </qandadiv>
- </qandaset>
- </section>
-
- <section xml:id="qandasetInternalRef">
- <title>Internal references</title>
-
- <qandaset defaultlabel="qanda" xml:id="example_book.dtd_v5">
- <title>book.xsd and internal references</title>
-
- <qandadiv>
- <qandaentry>
- <question>
- <para>We want to extend <xref
- linkend="example_book.dtd_v3"/> schema to allow for document
- internal references by:</para>
+ </answer>
+ </qandaentry>
+ </qandadiv>
+ </qandaset>
+ </section>
- <itemizedlist>
- <listitem>
- <para>Allowing each <tag class="starttag">chapter</tag>,
- <tag class="starttag">para</tag> and <tag
- class="starttag">itemizedlist</tag> to become reference
- targets.</para>
- </listitem>
+ <section xml:id="sectMixQuotes">
+ <title>Mixing attribute quotes</title>
- <listitem>
- <para>Extending the element <tag
- class="element">para</tag>'s mixed content model by a
- new element <tag class="element">link</tag> with an
- attribute <tag class="attribute">linkend</tag> being a
- reference to a target.</para>
- </listitem>
- </itemizedlist>
- </question>
+ <qandaset defaultlabel="qanda" xml:id="example_quotes">
+ <title>Single and double quotes reconsidered</title>
- <answer>
- <para>We extend our schema:</para>
+ <qandadiv>
+ <qandaentry>
+ <question>
+ <para>We recall the problem of nested quotes yielding non-well
+ formed XML code:</para>
+
+ <programlisting language="none"><img src="bold.gif" alt="We may use "quotes" here" /></programlisting>
+
+ <para>The XML specification defines legal attribute value
+ definitions as:</para>
+
+ <productionset>
+ <title><link
+ xlink:href="http://www.w3.org/TR/2008/REC-xml-20081126/#d0e888">Literals</link></title>
+
+ <production xml:id="w3RecXml_NT-EntityValue">
+ <lhs>EntityValue</lhs>
+
+ <rhs>'"' ([^%&"] | <nonterminal
+ def="#w3RecXml_NT-PEReference">PEReference</nonterminal> |
+ <nonterminal
+ def="#w3RecXml_NT-Reference">Reference</nonterminal>)* '"'
+ |Â "'" ([^%&'] | <nonterminal
+ def="#w3RecXml_NT-PEReference">PEReference</nonterminal> |
+ <nonterminal
+ def="#w3RecXml_NT-Reference">Reference</nonterminal>)*
+ "'"</rhs>
+ </production>
+
+ <production xml:id="w3RecXml_NT-AttValue">
+ <lhs>AttValue</lhs>
+
+ <rhs>'"' ([^<&"] | <nonterminal
+ def="#w3RecXml_NT-Reference">Reference</nonterminal>)* '"'
+ |Â "'" ([^<&'] | <nonterminal
+ def="#w3RecXml_NT-Reference">Reference</nonterminal>)*
+ "'"</rhs>
+ </production>
+
+ <production xml:id="w3RecXml_NT-SystemLiteral">
+ <lhs>SystemLiteral</lhs>
+
+ <rhs>('"' [^"]* '"') |Â ("'" [^']* "'")</rhs>
+ </production>
+
+ <production xml:id="w3RecXml_NT-PubidLiteral">
+ <lhs>PubidLiteral</lhs>
+
+ <rhs>'"' <nonterminal
+ def="#w3RecXml_NT-PubidChar">PubidChar</nonterminal>* '"'
+ | "'" (<nonterminal
+ def="#w3RecXml_NT-PubidChar">PubidChar</nonterminal> -
+ "'")* "'"</rhs>
+ </production>
+
+ <production xml:id="w3RecXml_NT-PubidChar">
+ <lhs>PubidChar</lhs>
+
+ <rhs>#x20 | #xD | #xA |Â [a-zA-Z0-9]
+ |Â [-'()+,./:=?;!*#@$_%]</rhs>
+ </production>
+ </productionset>
+
+ <para>Find out how it is possible to set the attribute <tag
+ class="attribute">alt</tag>'s value to the string <code>We may
+ use "quotes" here</code>.</para>
+ </question>
- <programlisting language="none"><?xml version="1.0" encoding="UTF-8"?>
+ <answer>
+ <para>The production rule for attribute values reads:</para>
+
+ <productionset>
+ <productionrecap linkend="w3RecXml_NT-AttValue"/>
+ </productionset>
+
+ <para>This allows us to use either of two alternatives to
+ delimit attribute values:</para>
+
+ <glosslist>
+ <glossentry>
+ <glossterm><tag class="starttag">img ...
+ alt="..."/</tag></glossterm>
+
+ <glossdef>
+ <para><emphasis>Validity constraint:</emphasis> do not
+ use <code>"</code> inside the value string.</para>
+ </glossdef>
+ </glossentry>
+
+ <glossentry>
+ <glossterm><tag class="starttag">img ...
+ alt='...'/</tag></glossterm>
+
+ <glossdef>
+ <para><emphasis>Validity constraint:</emphasis> do not
+ use <code>'</code> inside the value string.</para>
+ </glossdef>
+ </glossentry>
+ </glosslist>
+
+ <para>We may take advantage of the second rule:</para>
+
+ <programlisting language="none"><img src="bold.gif" alt='We may use "quotes" here' /></programlisting>
+
+ <para>Notice that according to <xref
+ linkend="w3RecXml_NT-AttValue"/> the delimiting quotes must
+ not be mixed. The following code is thus not well
+ formed:</para>
+
+ <programlisting language="none"><img src="bold.gif'/></programlisting>
+ </answer>
+ </qandaentry>
+ </qandadiv>
+ </qandaset>
+ </section>
+
+ <section xml:id="qandasetInternalRef">
+ <title>Internal references</title>
+
+ <qandaset defaultlabel="qanda" xml:id="example_book.dtd_v5">
+ <title>book.xsd and internal references</title>
+
+ <qandadiv>
+ <qandaentry>
+ <question>
+ <para>We want to extend <xref linkend="example_book.dtd_v3"/>
+ schema to allow for document internal references by:</para>
+
+ <itemizedlist>
+ <listitem>
+ <para>Allowing each <tag class="starttag">chapter</tag>,
+ <tag class="starttag">para</tag> and <tag
+ class="starttag">itemizedlist</tag> to become reference
+ targets.</para>
+ </listitem>
+
+ <listitem>
+ <para>Extending the element <tag
+ class="element">para</tag>'s mixed content model by a new
+ element <tag class="element">link</tag> with an attribute
+ <tag class="attribute">linkend</tag> being a reference to
+ a target.</para>
+ </listitem>
+ </itemizedlist>
+ </question>
+
+ <answer>
+ <para>We extend our schema:</para>
+
+ <programlisting language="none"><?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:vc="http://www.w3.org/2007/XMLSchema-versioning" elementFormDefault="qualified"
vc:minVersion="1.0" vc:maxVersion="1.1">
@@ -1721,9 +1724,9 @@ public class Memo {
<xs:element name="title" type="xs:string"/>
<xs:element name="link">
<xs:complexType mixed="true"> <co
- xml:id="progamlisting_book_v5_link"/>
+ xml:id="progamlisting_book_v5_link"/>
<xs:attribute name="linkend" <co
- xml:id="progamlisting_book_v5_link_linkend"/> type="xs:IDREF" use="required"/>
+ xml:id="progamlisting_book_v5_link_linkend"/> type="xs:IDREF" use="required"/>
</xs:complexType>
</xs:element>
@@ -1750,21 +1753,21 @@ public class Memo {
</xs:sequence>
<xs:attribute ref="lang" use="optional"/>
<xs:attribute name="id" <co
- xml:id="progamlisting_book_v5_chapter_id"/> type="xs:ID" use="optional"/>
+ xml:id="progamlisting_book_v5_chapter_id"/> type="xs:ID" use="optional"/>
<xs:attribute ref="xml:base"/> <!-- This allows for <xi:include ...> -->
</xs:complexType>
</xs:element>
<xs:element name="para">
<xs:complexType mixed="true"> <co
- xml:id="progamlisting_book_v5_mixed_link"/>
+ xml:id="progamlisting_book_v5_mixed_link"/>
<xs:choice minOccurs="0" maxOccurs="unbounded">
<xs:element ref="emphasis"/>
<xs:element ref="link"/>
</xs:choice>
<xs:attribute ref="lang" use="optional"/>
<xs:attribute name="id" <co
- xml:id="progamlisting_book_v5_para_id"/> type="xs:ID" use="optional"/>
+ xml:id="progamlisting_book_v5_para_id"/> type="xs:ID" use="optional"/>
</xs:complexType>
</xs:element>
@@ -1790,43 +1793,42 @@ public class Memo {
</xs:schema></programlisting>
- <calloutlist>
- <callout arearefs="progamlisting_book_v5_chapter_id">
- <para>Defining an attribute <tag
- class="attribute">id</tag> of type <code>ID</code> for
- the elements <tag class="element">chapter</tag>, <tag
- class="element">para</tag> and <tag
- class="element">itemizedList</tag>. This enables an
- author to define internal reference targets.</para>
- </callout>
-
- <callout arearefs="progamlisting_book_v5_mixed_link">
- <para>A link is part of the element <tag
- class="element">para</tag>'s mixed content model. Thus
- an author may define internal references along with
- ordinary text.</para>
- </callout>
-
- <callout arearefs="progamlisting_book_v5_link">
- <para>Like in HTML a link may contain text. If converted
- to HTML the formatting expectation is a hypertext
- link.</para>
- </callout>
-
- <callout arearefs="progamlisting_book_v5_link_linkend">
- <para>The attribute <tag class="attribute">linkend</tag>
- holds the reference to an internal target being either a
- <tag class="element">chapter</tag>, a <tag
- class="element">para</tag> or an <tag
- class="element">itemizedList</tag>.</para>
- </callout>
- </calloutlist>
- </answer>
- </qandaentry>
- </qandadiv>
- </qandaset>
- </section>
+ <calloutlist>
+ <callout arearefs="progamlisting_book_v5_chapter_id">
+ <para>Defining an attribute <tag
+ class="attribute">id</tag> of type <code>ID</code> for the
+ elements <tag class="element">chapter</tag>, <tag
+ class="element">para</tag> and <tag
+ class="element">itemizedList</tag>. This enables an author
+ to define internal reference targets.</para>
+ </callout>
+
+ <callout arearefs="progamlisting_book_v5_mixed_link">
+ <para>A link is part of the element <tag
+ class="element">para</tag>'s mixed content model. Thus an
+ author may define internal references along with ordinary
+ text.</para>
+ </callout>
+
+ <callout arearefs="progamlisting_book_v5_link">
+ <para>Like in HTML a link may contain text. If converted
+ to HTML the formatting expectation is a hypertext
+ link.</para>
+ </callout>
+
+ <callout arearefs="progamlisting_book_v5_link_linkend">
+ <para>The attribute <tag class="attribute">linkend</tag>
+ holds the reference to an internal target being either a
+ <tag class="element">chapter</tag>, a <tag
+ class="element">para</tag> or an <tag
+ class="element">itemizedList</tag>.</para>
+ </callout>
+ </calloutlist>
+ </answer>
+ </qandaentry>
+ </qandadiv>
+ </qandaset>
</section>
</section>
- </chapter>
-
+ </section>
+</chapter>