JAXB partielle unmarshalling Éléments sans @XMLRootElement

Je suis en utilisant le partielle unmarshalling exemple de JAXB, mais je suis incapable de unmarshal XML-Éléments qui ne sont pas sur le niveau de la racine (la cause qu'ils n'ont pas de @XmlRootElement tag). Dans mon exemple, j'ai essayé de lire le shipTo-Élément au lieu de purchaseOrder-Élément.

Normalement, je devrais travailler avec JAXBElement unmarshal(Source de source de,la Classe declaredType), mais comme l'exemple à l'aide d'un UnmarshallerHandler et un XMLFilterImpl je ne sais pas où en parler Jaxb la Classe qu'il doit utiliser.

Mon message d'erreur est: Causée par: javax.xml.bind.UnmarshalException: inattendu élément (uri:"", locale:"shipTo"). Éléments attendus sont <{}commentaire>,<{}purchaseOrder>,<{}purchaseOrders>

J'ai googlé autour d'un lot, mais n'ai rien trouvé d'utile encore.

Voici l'exemple de code à partir de la JaxB-site web:

Main.java

public class Main {
public static void main( String[] args ) throws Exception {

    //create JAXBContext for the primer.xsd
    JAXBContext context = JAXBContext.newInstance("primer");

    //create a new XML parser
    SAXParserFactory factory = SAXParserFactory.newInstance();
    factory.setNamespaceAware(true);
    XMLReader reader = factory.newSAXParser().getXMLReader();

    //prepare a Splitter
    Splitter splitter = new Splitter(context);

    //connect two components
    reader.setContentHandler(splitter);

    for( int i=0; i<args.length; i++ ) {
        //parse all the documents specified via the command line.
        //note that XMLReader expects an URL, not a file name.
        //so we need conversion.
        reader.parse(new File(args[i]).toURL().toExternalForm());
    }
}

}

Splitter.java

public class Splitter extends XMLFilterImpl {
public Splitter( JAXBContext context ) {
this.context = context;
}
/**
* We will create unmarshallers from this context.
*/
private final JAXBContext context;
public void startElement(String namespaceURI, String localName, String qName, Attributes atts)
throws SAXException {
if( depth!= 0 ) {
//we are in the middle of forwarding events.
//continue to do so.
depth++;
super.startElement(namespaceURI, localName, qName, atts);
return;
}
if( namespaceURI.equals("") && localName.equals("purchaseOrder") ) {
//start a new unmarshaller
Unmarshaller unmarshaller;
try {
unmarshaller = context.createUnmarshaller();
} catch( JAXBException e ) {
//there's no way to recover from this error.
//we will abort the processing.
throw new SAXException(e);
}
unmarshallerHandler = unmarshaller.getUnmarshallerHandler();
//set it as the content handler so that it will receive
//SAX events from now on.
setContentHandler(unmarshallerHandler);
//fire SAX events to emulate the start of a new document.
unmarshallerHandler.startDocument();
unmarshallerHandler.setDocumentLocator(locator);
Enumeration e = namespaces.getPrefixes();
while( e.hasMoreElements() ) {
String prefix = (String)e.nextElement();
String uri = namespaces.getURI(prefix);
unmarshallerHandler.startPrefixMapping(prefix,uri);
}
String defaultURI = namespaces.getURI("");
if( defaultURI!=null )
unmarshallerHandler.startPrefixMapping("",defaultURI);
super.startElement(namespaceURI, localName, qName, atts);
//count the depth of elements and we will know when to stop.
depth=1;
}
}
public void endElement(String namespaceURI, String localName, String qName) throws SAXException {
//forward this event
super.endElement(namespaceURI, localName, qName);
if( depth!=0 ) {
depth--;
if( depth==0 ) {
//just finished sending one chunk.
//emulate the end of a document.
Enumeration e = namespaces.getPrefixes();
while( e.hasMoreElements() ) {
String prefix = (String)e.nextElement();
unmarshallerHandler.endPrefixMapping(prefix);
}
String defaultURI = namespaces.getURI("");
if( defaultURI!=null )
unmarshallerHandler.endPrefixMapping("");
unmarshallerHandler.endDocument();
//stop forwarding events by setting a dummy handler.
//XMLFilter doesn't accept null, so we have to give it something,
//hence a DefaultHandler, which does nothing.
setContentHandler(new DefaultHandler());
//then retrieve the fully unmarshalled object
try {
JAXBElement<PurchaseOrderType> result = 
(JAXBElement<PurchaseOrderType>)unmarshallerHandler.getResult();
//process this new purchase order
process(result.getValue());
} catch( JAXBException je ) {
//error was found during the unmarshalling.
//you can either abort the processing by throwing a SAXException,
//or you can continue processing by returning from this method.
System.err.println("unable to process an order at line "+
locator.getLineNumber() );
return;
}
unmarshallerHandler = null;
}
}
}
public void process( PurchaseOrderType order ) {
System.out.println("this order will be shipped to "
+ order.getShipTo().getName() );
}
/**
* Remembers the depth of the elements as we forward
* SAX events to a JAXB unmarshaller.
*/
private int depth;
/**
* Reference to the unmarshaller which is unmarshalling
* an object.
*/
private UnmarshallerHandler unmarshallerHandler;
/**
* Keeps a reference to the locator object so that we can later
* pass it to a JAXB unmarshaller.
*/
private Locator locator;
public void setDocumentLocator(Locator locator) {
super.setDocumentLocator(locator);
this.locator = locator;
}
/**
* Used to keep track of in-scope namespace bindings.
* 
* For JAXB unmarshaller to correctly unmarshal documents, it needs
* to know all the effective namespace declarations.
*/
private NamespaceSupport namespaces = new NamespaceSupport();
public void startPrefixMapping(String prefix, String uri) throws SAXException {
namespaces.pushContext();
namespaces.declarePrefix(prefix,uri);
super.startPrefixMapping(prefix, uri);
}
public void endPrefixMapping(String prefix) throws SAXException {
namespaces.popContext();
super.endPrefixMapping(prefix);
}

}

Apprêt.xsd

    <xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<xsd:annotation>
<xsd:documentation xml:lang="en">
Purchase order schema for Example.com.
Copyright 2000 Example.com. All rights reserved.
</xsd:documentation>
</xsd:annotation>
<xsd:element name="purchaseOrders">
<xsd:complexType>
<xsd:sequence>
<xsd:element ref="purchaseOrder" minOccurs="0" maxOccurs="unbounded"/>
</xsd:sequence>
</xsd:complexType>
</xsd:element>
<xsd:element name="purchaseOrder" type="PurchaseOrderType"/>
<xsd:element name="comment" type="xsd:string"/>
<xsd:complexType name="PurchaseOrderType">
<xsd:sequence>
<xsd:element name="shipTo" type="USAddress"/>
<xsd:element name="billTo" type="USAddress"/>
<xsd:element ref="comment" minOccurs="0"/>
<xsd:element name="items" type="Items"/>
</xsd:sequence>
<xsd:attribute name="orderDate" type="xsd:date"/>
</xsd:complexType>
<xsd:complexType name="USAddress">
<xsd:sequence>
<xsd:element name="name" type="xsd:string"/>
<xsd:element name="street" type="xsd:string"/>
<xsd:element name="city" type="xsd:string"/>
<xsd:element name="state" type="xsd:string"/>
<xsd:element name="zip" type="xsd:decimal"/>
</xsd:sequence>
<xsd:attribute name="country" type="xsd:NMTOKEN"
fixed="US"/>
</xsd:complexType>
<xsd:complexType name="Items">
<xsd:sequence>
<xsd:element name="item" minOccurs="0" maxOccurs="unbounded">
<xsd:complexType>
<xsd:sequence>
<xsd:element name="productName" type="xsd:string"/>
<xsd:element name="quantity">
<xsd:simpleType>
<xsd:restriction base="xsd:positiveInteger">
<xsd:maxExclusive value="100"/>
</xsd:restriction>
</xsd:simpleType>
</xsd:element>
<xsd:element name="USPrice" type="xsd:decimal"/>
<xsd:element ref="comment" minOccurs="0"/>
<xsd:element name="shipDate" type="xsd:date" minOccurs="0"/>
</xsd:sequence>
<xsd:attribute name="partNum" type="SKU" use="required"/>
</xsd:complexType>
</xsd:element>
</xsd:sequence>
</xsd:complexType>
<!-- Stock Keeping Unit, a code for identifying products -->
<xsd:simpleType name="SKU">
<xsd:restriction base="xsd:string">
<xsd:pattern value="\d{3}-[A-Z]{2}"/>
</xsd:restriction>
</xsd:simpleType>
</xsd:schema>

test.xml

<purchaseOrders>
<!-- 1st -->
<purchaseOrder orderDate="1999-10-20">
<shipTo country="US">
<name>Alice Smith</name>
<street>123 Maple Street</street>
<city>Cambridge</city>
<state>MA</state>
<zip>12345</zip>
</shipTo>
<billTo country="US">
<name>Robert Smith</name>
<street>8 Oak Avenue</street>
<city>Cambridge</city>
<state>MA</state>
<zip>12345</zip>
</billTo>
<items/>
</purchaseOrder>
</purchaseOrders>
Quand je lance ton exemple j'ai "cette commande sera expédiée à Alice Smith".
Oui, bon! Le code fonctionne, mais si vous modifiez cette façon qu'il faut lire "shipTo" au lieu de "purchaseOrder" l'erreur est à venir

OriginalL'auteur cloudnaut | 2011-06-26