net.sf.saxon.dom
Class DOMEnvelope

java.lang.Object
  extended by net.sf.saxon.dom.DOMEnvelope
All Implemented Interfaces:
Serializable, ExternalObjectModel

public class DOMEnvelope
extends Object
implements ExternalObjectModel, Serializable

DOMEnvelope is an object model representation in which DOM interfaces are wrapped around Saxon NodeInfo nodes: that is, it implements the DOM on top of a Saxon tree implementation such as the tiny tree or linked tree.

See Also:
Serialized Form

Constructor Summary
DOMEnvelope()
           
 
Method Summary
 Value convertObjectToXPathValue(Object object, Configuration config)
          Convert a Java object to an XPath value.
 Object convertToNodeList(SequenceExtent extent)
          Convert a sequence of values to a NODELIST, as defined in the JAXP XPath API spec.
 Object convertXPathValueToObject(Value value, Class target, XPathContext context)
          Convert an XPath value to an object in this object model.
 Receiver getDocumentBuilder(Result result)
          Test whether this object model recognizes a particular kind of JAXP Result object, and if it does, return a Receiver that builds an instance of this data model from a sequence of events.
 boolean isRecognizedNode(Object object)
          Test whether this object model recognizes a given node as one of its own
 boolean isRecognizedNodeClass(Class nodeClass)
          Test whether this object model recognizes a given class as representing a node in that object model.
 boolean isRecognizedNodeListClass(Class nodeClass)
          Test whether this object model recognizes a given class as representing a list of nodes in that object model.
 boolean sendSource(Source source, Receiver receiver, PipelineConfiguration pipe)
          Test whether this object model recognizes a particular kind of JAXP Source object, and if it does, send the contents of the document to a supplied Receiver, and return true.
 NodeInfo unravel(Source source, Configuration config)
          Wrap or unwrap a node using this object model to return the corresponding Saxon node.
 DocumentInfo wrapDocument(Object node, String baseURI, Configuration config)
          Wrap a document node in the external object model in a document wrapper that implements the Saxon DocumentInfo interface.
 NodeInfo wrapNode(DocumentInfo document, Object node)
          Wrap a node in the external object model in a wrapper that implements the Saxon NodeInfo interface.
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

DOMEnvelope

public DOMEnvelope()
Method Detail

isRecognizedNode

public boolean isRecognizedNode(Object object)
Test whether this object model recognizes a given node as one of its own

Specified by:
isRecognizedNode in interface ExternalObjectModel
Parameters:
object - An object that possibly represents a node
Returns:
true if the object is a representation of a node in this object model

isRecognizedNodeClass

public boolean isRecognizedNodeClass(Class nodeClass)
Test whether this object model recognizes a given class as representing a node in that object model. This method will generally be called at compile time.

Specified by:
isRecognizedNodeClass in interface ExternalObjectModel
Parameters:
nodeClass - A class that possibly represents nodes
Returns:
true if the class is used to represent nodes in this object model

isRecognizedNodeListClass

public boolean isRecognizedNodeListClass(Class nodeClass)
Test whether this object model recognizes a given class as representing a list of nodes in that object model. This method will generally be called at compile time.

Specified by:
isRecognizedNodeListClass in interface ExternalObjectModel
Parameters:
nodeClass - A class that possibly represents nodes
Returns:
true if the class is used to represent nodes in this object model

getDocumentBuilder

public Receiver getDocumentBuilder(Result result)
                            throws XPathException
Test whether this object model recognizes a particular kind of JAXP Result object, and if it does, return a Receiver that builds an instance of this data model from a sequence of events. If the Result is not recognised, return null.

This implementation always returns null: it is not possible to construct an instance of this object model implementation directly as the result of a JAXP transformation.

Specified by:
getDocumentBuilder in interface ExternalObjectModel
Throws:
XPathException

sendSource

public boolean sendSource(Source source,
                          Receiver receiver,
                          PipelineConfiguration pipe)
                   throws XPathException
Test whether this object model recognizes a particular kind of JAXP Source object, and if it does, send the contents of the document to a supplied Receiver, and return true. Otherwise, return false.

This implementation returns true only if the source is a DOMSource whose contained node is a a "NodeOverNodeInfo".

Specified by:
sendSource in interface ExternalObjectModel
Throws:
XPathException

unravel

public NodeInfo unravel(Source source,
                        Configuration config)
Wrap or unwrap a node using this object model to return the corresponding Saxon node. If the supplied source does not belong to this object model, return null

Specified by:
unravel in interface ExternalObjectModel

convertObjectToXPathValue

public Value convertObjectToXPathValue(Object object,
                                       Configuration config)
                                throws XPathException
Convert a Java object to an XPath value. If the supplied object is recognized as a representation of a value using this object model, the object model should convert the value to an XPath value and return this as the result. If not, it should return null. If the object is recognized but cannot be converted, an exception should be thrown

Specified by:
convertObjectToXPathValue in interface ExternalObjectModel
Throws:
XPathException

convertXPathValueToObject

public Object convertXPathValueToObject(Value value,
                                        Class target,
                                        XPathContext context)
                                 throws XPathException
Convert an XPath value to an object in this object model. If the supplied value can be converted to an object in this model, of the specified class, then the conversion should be done and the resulting object returned. If the value cannot be converted, the method should return null. Note that the supplied class might be a List, in which case the method should inspect the contents of the Value to see whether they belong to this object model.

Specified by:
convertXPathValueToObject in interface ExternalObjectModel
Throws:
XPathException - if the target class is explicitly associated with this object model, but the supplied value cannot be converted to the appropriate class

wrapDocument

public DocumentInfo wrapDocument(Object node,
                                 String baseURI,
                                 Configuration config)
Wrap a document node in the external object model in a document wrapper that implements the Saxon DocumentInfo interface. (However, if the supplied object is a wrapper for a Saxon NodeInfo object, which is the case for this object model, then we unwrap it).

Specified by:
wrapDocument in interface ExternalObjectModel
Parameters:
node - a node (any node) in the third party document
baseURI - the base URI of the node (supply "" if unknown)
config - the Saxon configuration (which among other things provides access to the NamePool)
Returns:
the wrapper, which must implement DocumentInfo

wrapNode

public NodeInfo wrapNode(DocumentInfo document,
                         Object node)
Wrap a node in the external object model in a wrapper that implements the Saxon NodeInfo interface. (However, if the supplied object is a wrapper for a Saxon NodeInfo object, which is the case for this object model, then we unwrap it).

Specified by:
wrapNode in interface ExternalObjectModel
Parameters:
document - the document wrapper, as a DocumentInfo object
node - the node to be wrapped. This must be a node within the document wrapped by the DocumentInfo provided in the first argument
Returns:
the wrapper for the node, as an instance of VirtualNode

convertToNodeList

public Object convertToNodeList(SequenceExtent extent)
Convert a sequence of values to a NODELIST, as defined in the JAXP XPath API spec. This method is used when the evaluate() request specifies the return type as NODELIST, regardless of the actual results of the expression. If the sequence contains things other than nodes, the fallback is to return the sequence as a Java List object. The method can return null to invoke fallback behaviour.

Specified by:
convertToNodeList in interface ExternalObjectModel


Copyright (C) Michael H. Kay. All rights reserved.