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diff --git a/docs/org.eclipse.wst.xsdeditor.doc.user/topics/rnmspc.html b/docs/org.eclipse.wst.xsdeditor.doc.user/topics/rnmspc.html deleted file mode 100644 index 3686085fee..0000000000 --- a/docs/org.eclipse.wst.xsdeditor.doc.user/topics/rnmspc.html +++ /dev/null @@ -1,255 +0,0 @@ -<?xml version="1.0" encoding="UTF-8"?> -<!DOCTYPE html - PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> -<html> -<head> -<!-- /******************************************************************************* - * Copyright (c) 2000, 2005 IBM Corporation and others. - * All rights reserved. This program and the accompanying materials - * are made available under the terms of the Eclipse Public License v1.0 - * which accompanies this distribution, and is available at - * http://www.eclipse.org/legal/epl-v10.html - * - * Contributors: - * IBM Corporation - initial API and implementation - *******************************************************************************/ --> -<link rel="stylesheet" type="text/css" href="../../org.eclipse.wst.doc.user/common.css" /> -<title>XML namespaces</title> -</head> -<body id="rnmspc"><a name="rnmspc"><!-- --></a> - -<h1 class="topictitle1">XML namespaces</h1> -<div><p>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.</p> -<div><div class="skipspace">XML namespaces are defined by a W3C recommendation, dating 14 January -1999, called <a href="http://www.w3.org/TR/REC-xml-names/">Namespaces -in XML</a>. XML tag names should be globally unique, as well as short for -performance reasons. In order to resolve this conflict, the W3C namespace -recommendation defines an attribute xmlns which can amend any XML element. -If it is present in an element, it identifies the namespace for this element.</div> -<div class="skipspace"><p>The xmlns attribute has the following syntax:</p> -<p><samp class="codeph"> xmlns: <var class="varname">prefix</var>:namespace</samp> </p> -<p>where <samp class="codeph">namespace</samp> is a unique URI (such as www.ibm.com) and where <samp class="codeph"><var class="varname">prefix</var></samp> represents -the namespace and provides a pointer to it.</p> -<p>In the following customer -element definition, an accounting namespace is defined in order to be able -to distinguish the element tags from those appearing in customer records created -by other business applications:</p> -<div class="p"><pre><acct:customer xmlns:acct="http://www.my.com/acct-REV10"> - <acct:name>Corporation</acct:name> - <acct:order acct:ref="5566"/> - <acct:status>invoice</acct:status> -</acct:customer> </pre> - </div> -<p>The <i>namespace definition</i> in -the first line assigns the namespace <i>http://www.my.com/acct-REV10</i> to -the prefix. This prefix is used on the element names such as name in order -to attach them to the namespace. A second application, for example, a fulfillment -system, can assign a different namespace to its customer elements:</p> -<div class="p"><pre><ful:customer xmlns:ful="http://www.your.com/ful"> - <ful:name>Corporation</ful:name> - <ful:order ful:ref="A98756"/> - <ful:status>shipped</ful:status> - </ful:customer></pre> - </div> -<p>An application processing both data -structures is now able to treat the accounting and the fulfillment data differently. -There is a default namespace. It is set if no local name is assigned in the -namespace definition:</p> -<div class="p"><pre><acct:customer xmlns="http://www.my.com/acct-REV10" xmlns:acct="http://www.my.com/acct-REV10 "> -<name>Corporation</name> -<order acct:ref="5566"/> -<status>invoice</status> -</customer></pre> -</div> -<p>In this example, all tags in the customer -record are qualified to reside in the namespace <i>http://www.my.com/acct-REV10.</i> No -explicit prefix is needed because the default namespace is used. Note that -the default namespace applies to any attributes definitions.</p> -</div> -<div class="skipspace"><h4 class="sectiontitle">XML schemas and namespaces</h4><p>In the XML schema below, -the default namespace for the schema is defined as the standard XML schema -namespace <i>http://www.w3.org/2001/XMLSchem</i>a; there is also a schema -specific namespace <i>http://www.ibm.com</i>.</p> -<div class="p"><pre><?xml version="1.0"> -<schema xmlns="http://www.w3.org/2001/XMLSchema" targetNamespace="http://www.ibm.com" xmlns:TestSchema="http://www.ibm.com"> - <simpleType name="ZipCodeType"> - <restriction base="integer"> - <minInclusive value="10000"/> - <maxInclusive value="99999"/> -</restriction> - </simpleType> - <!--element definitions skipped --> -</schema> </pre> -</div> -<p>Assuming that the preceding XML schema is -is saved as <span class="filepath">C:\temp\TestSchema.xsd</span>, a sample XML file -that validates against this schema is:</p> -<div class="p"><pre><?xml version="1.0"> -<x:addressList xmlns:x="http://www.ibm.com" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.ibm.com file:///C:/temp/TestSchema.xsd"> - xsi:schemaLocation="http://www.ibm.com file:///C:/temp/TestSchema.xsd"> -<x:address> - <x:street>x:Vangerowstrasse</x:street> - <x:zipCode>69115</x:zipCode> - <x:city>x:Heidelberg</x:city> - </x:address> - <x:address> -<x:street>x:Bernal Road</x:street> -<x:zipCode>90375</x:zipCode> - <x:city>x:San Jose</x:city> - </x:address> -</x:addressList> </pre> -</div> -</div> -<div class="skipspace"><h4 class="sectiontitle">Target namespace</h4><p> The target namespace serves to -identify the namespace within which the association between the element and -its name exists. In the case of declarations, this association determines -the namespace of the elements in XML files conforming to the schema. An XML -file importing a schema must reference its target namespace in the schemaLocation -attribute. Any mismatches between the target and the actual namespace of an -element are reported as schema validation errors. In our example, the target -namespace is http://www.ibm.com; it is defined in the XML schema file and -referenced twice in the XML file. Any mismatch between these three occurrences -of the namespace lead to validation errors.</p> -<p> The following examples -show how target namespaces and namespace prefixes work in XML schemas and -their corresponding XML instance documents.</p> -</div> -<div class="skipspace"><h4 class="sectiontitle">Sample 1 - A schema with both a default and target namespace -and unqualified locals</h4><p>The XML schema: </p> -<div class="p"><pre><?xml version="1.0"> -<schema xmlns="http://www.w3.org/2001/XMLSchema" targetNamespace="http://www.ibm.com" xmlns:x="http://www.ibm.com"> -<complexType name="AddressType"> -<sequence> -<element name="name" type="string"></element> -</sequence> -</complexType> -<element name="MyAddress" type="x:AddressType"></element> -</schema> </pre> - </div> -<p>A valid XML instance document created from -this schema looks like this. Local elements and attributes are <i>unqualified</i>.</p> -<div class="p"><pre><?xml version="1.0"> -<x:MyAddress xmlns:x="http://www.ibm.com" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.ibm.com x.xsd "> -<name>Peter Smith</name> -</x:MyAddress> </pre> -</div> -<p>When local elements (such as the <i>"name"</i> element) -and attributes are unqualified in an XML file, then only the root element -is qualified. So, in this example, the <i>"x"</i> namespace prefix is assigned -to the root element <i>"MyAddress"</i>, associating it with the namespace <i>"http://www.ibm.com",</i> but -the<i>"x"</i> prefix is not assigned to the local element <i>"name"</i>.</p> -</div> -<div class="skipspace"><h4 class="sectiontitle">Sample 2 - A schema with both a default and target namespace -and qualified locals</h4><div class="p"><pre><?xml version="1.0"> -<schema xmlns="http://www.w3.org/2001/XMLSchema" targetNamespace="http://www.ibm.com" xmlns:x="http://www.ibm.com" elementFormDefault="qualified"> -<complexType name="AddressType"> -<sequence> -<element name="name" type="string"></element> -</sequence> -</complexType> -<element name="MyAddress" type="x:AddressType"></element> - </schema> </pre> -</div> -<p>A valid XML instance document created from -this schema looks like this. Local elements and attributes are <i>qualified</i> This -is because the elementFormDefault attribute is set to qualified in the XML -schema.</p> -<div class="p"><pre><?xml version="1.0"> - <x:MyAddress xmlns:x="http://www.ibm.com" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" - xsi:schemaLocation="http://www.ibm.com x.xsd "> -<x:name>Peter Smith</x:name> - </x:MyAddress></pre> - </div> -<p>In this example, the <i>"x"</i> namespace -prefix is assigned to both the root element <i>"MyAddress"</i> and the local -element <i>"name"</i>, associating them with the namespace <i>"http://www.ibm.com",</i>.</p> -</div> -<div class="skipspace"><h4 class="sectiontitle">Sample 3 - Schema with target Namespace, and explicitly defines -xmlns:xsd</h4><p>This XML schema adds this attribute: </p> -<samp class="codeph">xmlns:xsd="http://www.w3.org/2001/XMLSchema </samp><p>What -this means is that each of the constructs that are defined by the XML schema -language will need to be qualified with the <var class="varname">"xsd"</var> prefix. -For example, xsd:complexType and xsd:string</p> -<p>. Note that you can chose -any other prefixes such as <var class="varname">"xs"</var> or <var class="varname">"foobar"</var> in -your declaration and usage.</p> -<p>You can specify this prefix in the XML Schema -preferences page. For more information, refer to the related tasks below.</p> -<p>All -user defined types belong to the namespace http://www.ibm.com as defined -by the targetNamespace attribute, and the prefix is <i>"x"</i> as defined -by the xmlns:x attribute.</p> -<div class="p"><pre><?xml version="1.0"> -<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema" targetNamespace="http://www.ibm.com" xmlns:x="http://www.ibm.com"> -<xsd:complexType name="AddressType"> -<xsd:sequence> - <xsd:element name="name" type="xsd:string"></xsd:element> -</xsd:sequence> - </xsd:complexType> - <xsd:element name="MyAddress" type="x:AddressType"></xsd:element> -</xsd:schema></pre> - </div> -<p>A valid XML instance document created -from this schema looks like this. Local elements and attributes are <i>unqualified</i>. -The semantics of qualification is the same as Sample 1.</p> -<div class="p"><pre><?xml version="1.0"> - <x:MyAddress xmlns:x="http://www.ibm.com" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://www.ibm.com x.xsd "> -<name>Peter Smith</name> - </x:MyAddress></pre> -</div> -</div> -<div class="skipspace"><h4 class="sectiontitle">Sample 4 - Schema with undeclared target Namespace that explicitly -defines xmlns:xsd</h4><p>This XML schema has no target namespace for itself. -In this case, it is highly recommended that all XML schema constructs be explicitly -qualified with a prefix such as <i>"xsd"</i>. The definitions and declarations -from this schema such as <i>AddressType</i> are referenced without namespace -qualification since there is no namespace prefix. </p> -<div class="p"><pre><?xml version="1.0"> -<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"> -<xsd:complexType name="AddressType"> -<xsd:sequence> -<xsd:element name="name" type="xsd:string"></xsd:element> -<xsd:element name="name" type="xsd:string"></xsd:element> -<xsd:element name="name" type="xsd:string"></xsd:element> -</xsd:sequence> -</xsd:complexType> -<xsd:element name="MyAddress" type="AddressType"></xsd:element> -</xsd:schema> </pre> -</div> -<p>A valid XML instance document created -from the schema looks like this. All elements are <i>unqualified</i>.</p> -<div class="p"><pre><?xml version="1.0"> -<MyAddress xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="x.xsd"> -<name>name</name> -</MyAddress></pre> - </div> -</div> -<div class="skipspace"><h4 class="sectiontitle">Sample 5 - A schema where the target namespace is the default -namespace</h4><p>This is an XML schema where the target namespace is the -default namespace. As well, the namespace has no namespace prefix.</p> -<div class="p"><pre><?xml version="1.0"> - <xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema" targetNamespace="http://www.ibm.com" xmlns="http://www.ibm.com"> -<xsd:complexType name="AddressType"> -<xsd:sequence> -<xsd:element name="name" type="xsd:string"></xsd:element> -</xsd:sequence> -</xsd:complexType> - <xsd:element name="MyAddress" type="AddressType"></xsd:element> - </xsd:schema> </pre> - </div> -<p>A valid XML instance document created -from the schema looks like this:</p> -<div class="p"><pre><?xml version="1.0" encoding="UTF-8"> -<MyAddress xmlns="http://www.ibm.com" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.ibm.com NewXMLSchema.xsd"> -<name>name</name> - </MyAddress> </pre> - </div> -</div> -</div> -<div><div class="reltasks"><strong>Related tasks</strong><br /> -<div><a href="../topics/tedtpref.html" title="You can set various preferences for XML schema files such as the default target namespace and XML Schema language constructs prefix used.">Editing XML schema file preferences</a></div> -</div> -</div></body> -</html>
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