XSD Tutorials - Herong's Tutorial Examples - v5.23, by Herong Yang
Including Old Schema Documents - Errors
This section describes a tutorial example of element declaration and datatype definition colliding with those in the included schema.
When an "include" component is used, the specified schema document is actually merged into the current schema document to represent a single schema.
As a single schema, you need to watch out some schema general rules like:
Rule 1. A global element can not be declared more than once.
Rule 2. A global datatype can not be defined more than once.
For example, the schema, address_include_error.xsd, listed below has two errors. It is trying to re-define "addressType" and re-declare "address".
<?xml version="1.0"?> <xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"> <xsd:annotation> <xsd:documentation>address_include_error.xsd - Copyright (c) 2002-2013 HerongYang.com. All Rights Reserved. </xsd:documentation> </xsd:annotation> <xsd:include schemaLocation="address.xsd"> </xsd:include> <xsd:element name="address" type="addressType"/> <xsd:complexType name="addressType"> <xsd:sequence> <xsd:element name="street" type="xsd:string"/> <xsd:element name="city" type="xsd:string"/> <xsd:element name="state" type="xsd:string"/> <xsd:element name="zip" type="xsd:string"/> </xsd:sequence> </xsd:complexType> </xsd:schema>
Here are the errors reported by the schema checker program, XsdSchemaChecker.java:
herong> java XsdSchemaChecker address_include_error.xsd Error: Line number: 7 Column number: 50 Message: sch-props-correct.2: A schema cannot contain two global components with the same name; this schema contains two occurrences of ',address'. Error: Line number: 9 Column number: 38 Message: sch-props-correct.2: A schema cannot contain two global components with the same name; this schema contains two occurrences of ',addressType'. Failed with 2 errors.
Table of Contents
XML Editor and Schema Processor - XMLPad
Java API for XML Processing - JAXP
JAXP - XML Schema (XSD) Validation
Xerces2 Java Parser - Java API of XML Parsers
Introduction of XSD Built-in Datatypes
"string" and Its Derived Datatypes
"decimal" and Its Derived Datatypes
"dateTime" and Its Related Datatypes
Miscellaneous Built-in Datatypes
Facets, Constraining Facets and Restriction Datatypes
"simpleType" - Defining Your Own Simple Datatypes
Identity-Constraints: unique, key and keyref
Assertion as Custom Validation Rules
XML Schema Location and Namespace in XML Documents
Overriding Element Types in XML Documents
►Linking Multiple Schema Documents Together
Schema Component Reuse - "include", "redefine" or "import"
Including Old Schema Documents - "include" Component
Including Old Schema Documents - Examples
►Including Old Schema Documents - Errors
Redefining Old Datatypes - "redefine" Component
Redefining Old Datatypes - XML Examples
Redefining Old Datatypes - Errors
Importing Declarations Across Namespaces - "import" Component
Importing Declarations Across Namespaces - Examples
Using Elements Declared in Different Namespaces