Hello, I have a problem regarding the use of substitution groups and class loaders. In practise, I get an exception when trying to access a base class defined in a plugin which has been loaded with a typical class loader. Below I give the schema definition and source code:
1. I have created the following XSD (simple_agenda.xsd): <?xml version="1.0" encoding="UTF-8"?> <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"; elementFormDefault="qualified" attributeFormDefault="unqualified"> <xs:element name="agenda"> <xs:complexType> <xs:sequence> <xs:element name="version" type="xs:string"/> <xs:element ref="person" maxOccurs="unbounded"/> </xs:sequence> </xs:complexType> </xs:element> <xs:element name="person" type="personType" abstract="false"/> <xs:complexType name="personType" abstract="true"> <xs:sequence> <xs:element name="name" type="xs:string"/> </xs:sequence> </xs:complexType> <xs:complexType name="friendType"> <xs:complexContent> <xs:extension base="personType"> <xs:sequence> <xs:element name="telephone" type="xs:string"/> </xs:sequence> </xs:extension> </xs:complexContent> </xs:complexType> <xs:element name="friend" type="friendType" abstract="false" substitutionGroup="person"/> </xs:schema> This schema has then been compiled with XmlBeans scomp command into a JAR file (simple_agenda.jar). 2. An example of XML file which follows the previous XSD (agenda.xml): <?xml version="1.0" encoding="UTF-8"?> <agenda xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"; xsi:noNamespaceSchemaLocation="simple_agenda.xsd"> <version>1.0.0</version> <friend> <name>Some name</name> <telephone>0123456789</telephone> </friend> </agenda> 3. The following is a plugin (SimpleAgendaImporter.java) used to load the XML file agenda.xml: package com.mycompany.xmlimport; import java.io.File; import java.io.IOException; import noNamespace.AgendaDocument; import noNamespace.PersonType; import org.apache.xmlbeans.XmlException; public class SimpleAgendaImporter implements Importer { public boolean loadFile(File input_xmlFile) { AgendaDocument agenda_doc = null; try { agenda_doc = AgendaDocument.Factory.parse(input_xmlFile); } catch (XmlException ex) { ex.printStackTrace(); } catch (IOException ex) { ex.printStackTrace(); } AgendaDocument.Agenda root_agenda = agenda_doc.getAgenda(); String version = root_agenda.getVersion(); System.out.println("Version: " + version ); int num_persons = root_agenda.sizeOfPersonArray(); PersonType person; for (int i_per = 0; i_per < num_persons; i_per++) { person = root_agenda.getPersonArray(i_per); System.out.println("Current person's name: " + person.getName()); } return true; } } N.B.: the compiled JAR for this plugin has been named AgendaImporter.jar. 4. In the following main program I load and (try to) execute the previous plugin: package agendamanager; import com.mycompany.xmlimport.IImporterFactory; import com.mycompany.xmlimport.Importer; import java.io.File; import java.io.FilenameFilter; import java.net.MalformedURLException; import java.net.URL; import java.net.URLClassLoader; public class Main { public Main() { } public static void main(String[] args) { // --- Load the agenda entries String plugin_dirname = "plugins"; File plugin_dir = new File(plugin_dirname); File plugin_file = new File(plugin_dir, "AgendaImporter.jar"); IImporterFactory importer_factory = null; Importer importer = null; URLClassLoader fileScroll = null; Class c = null; System.out.println("Loading jar for AGENDA import..."); try { fileScroll = new URLClassLoader( new URL[]{plugin_file.toURI().toURL()}); } catch (MalformedURLException ex) { ex.printStackTrace(); return; } try { c = fileScroll.loadClass( "com.mycompany.xmlimport.ImporterFactory"); } catch (ClassNotFoundException ex) { System.out.println("Current plug-in (file " + plugin_file.getName() + ") is not for agenda import (I)."); return; } try { importer_factory = (IImporterFactory) c.newInstance(); } catch (IllegalAccessException ex) { ex.printStackTrace(); } catch (InstantiationException ex) { System.out.println("Current plug-in (file " + plugin_file.getName() + ") is not for agenda import (II)."); return; } importer = importer_factory.getInstance(); File xml_agenda = new File("data/agenda.xml"); System.out.println("Parsing agenda from file " + xml_agenda.getName()); importer.loadFile(xml_agenda); } } 5. Here follows the Importer interface... package com.mycompany.xmlimport; import java.io.File; public interface Importer { boolean loadFile( File input_xmlFile ); } 6. Here follows the class IImporterFactory... package com.mycompany.xmlimport; public interface IImporterFactory { public Importer getInstance(); } 7. Here follows the class ImporterFactory... package com.mycompany.xmlimport; public class ImporterFactory implements IImporterFactory { public SimpleAgendaImporter getInstance() { return new SimpleAgendaImporter(); } } ================================================================== When executing the main program I get the following exception Exception in thread "main" java.lang.ClassCastException: org.apache.xmlbeans.impl.values.XmlAnyTypeImpl cannot be cast to noNamespace.PersonType at noNamespace.impl.AgendaDocumentImpl$AgendaImpl.getPersonArray( Unknown Source) at this line person = root_agenda.getPersonArray(i_per); of the plugin. However, if I read in the file agenda.xml directly from the main program (see below), I do not get any exception: ---------------------------------------------------------------- package agendamanager; import com.mycompany.xmlimport.Importer; import com.mycompany.xmlimport.SimpleAgendaImporter; import java.io.File; public class Main { public Main() { } public static void main(String[] args) { // --- Load the agenda entries Importer importer = new SimpleAgendaImporter(); File xml_agenda = new File("data/agenda.xml"); System.out.println("Parsing agenda from file " + xml_agenda.getName()); importer.loadFile(xml_agenda); } } ---------------------------------------------------------------- Maybe this kind of problem or a similar one has been implicitly solved in some other mail in this forum, but I really did not succeed in extrapolating a solution to my case. Maybe the XSD can be slightly modified in order to overcome the problem? Thanks to all, S. 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