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The XSLT and XQuery Processor
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Copyright (c) 2018-2023 Saxonica Limited
// This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
// If a copy of the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
// This Source Code Form is "Incompatible With Secondary Licenses", as defined by the Mozilla Public License, v. 2.0.
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
package net.sf.saxon.option.jdom2;
import net.sf.saxon.Configuration;
import net.sf.saxon.event.Builder;
import net.sf.saxon.event.PipelineConfiguration;
import net.sf.saxon.event.Receiver;
import net.sf.saxon.expr.JPConverter;
import net.sf.saxon.expr.PJConverter;
import net.sf.saxon.expr.XPathContext;
import net.sf.saxon.lib.ExternalObjectModel;
import net.sf.saxon.lib.NamespaceConstant;
import net.sf.saxon.om.*;
import net.sf.saxon.pattern.AnyNodeTest;
import net.sf.saxon.tree.wrapper.VirtualNode;
import net.sf.saxon.type.ItemType;
import org.jdom2.*;
import javax.xml.transform.Result;
import javax.xml.transform.Source;
/**
* This interface must be implemented by any third-party object model that can
* be wrapped with a wrapper that implements the Saxon Object Model (the NodeInfo interface).
* This implementation of the interface supports wrapping of JDOM Documents.
*/
public class JDOM2ObjectModel extends TreeModel implements ExternalObjectModel {
private static final JDOM2ObjectModel THE_INSTANCE = new JDOM2ObjectModel();
public static JDOM2ObjectModel getInstance() {
return THE_INSTANCE;
}
public JDOM2ObjectModel() {
}
/**
* Get the name of a characteristic class, which, if it can be loaded, indicates that the supporting libraries
* for this object model implementation are available on the classpath
*
* @return by convention (but not necessarily) the class that implements a document node in the relevant
* external model
*/
@Override
public String getDocumentClassName() {
return "org.jdom2.Document";
}
/**
* Get the URI of the external object model as used in the JAXP factory interfaces for obtaining
* an XPath implementation
*/
@Override
public String getIdentifyingURI() {
return NamespaceConstant.OBJECT_MODEL_JDOM;
}
@Override
public Builder makeBuilder(PipelineConfiguration pipe) {
return new JDOM2Writer(pipe);
}
@Override
public int getSymbolicValue() {
return Builder.JDOM2_TREE;
}
@Override
public String getName() {
return "JDOM2";
}
/**
* Test whether this object model recognizes a given node as one of its own
*
* @param object the object in question
* @return true if the object is a JDOM node
*/
private static boolean isRecognizedNode(Object object) {
return object instanceof Document ||
object instanceof Element ||
object instanceof Attribute ||
object instanceof Text ||
object instanceof Comment ||
object instanceof ProcessingInstruction ||
object instanceof Namespace;
}
@Override
public PJConverter getPJConverter(Class targetClass) {
if (isRecognizedNodeClass(targetClass)) {
return new PJConverter() {
@Override
public Object convert(Sequence value, Class targetClass, XPathContext context) {
return convertXPathValueToObject(value, targetClass);
}
};
} else {
return null;
}
}
@Override
public JPConverter getJPConverter(Class sourceClass, Configuration config) {
if (isRecognizedNodeClass(sourceClass)) {
return new JPConverter() {
@Override
public GroundedValue convert(Object object, XPathContext context) {
return convertObjectToXPathValue(object, context.getConfiguration());
}
@Override
public ItemType getItemType() {
return AnyNodeTest.getInstance();
}
};
} else {
return null;
}
}
/**
* Get a converter that converts a sequence of XPath nodes to this model's representation
* of a node list.
*
* @param node an example of the kind of node used in this model
* @return if the model does not recognize this node as one of its own, return null. Otherwise
* return a PJConverter that takes a list of XPath nodes (represented as NodeInfo objects) and
* returns a collection of nodes in this object model
*/
@Override
public PJConverter getNodeListCreator(Object node) {
return null;
}
/**
* 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.
*
* @param nodeClass A class that possibly represents nodes
* @return true if the class is used to represent nodes in this object model
*/
private boolean isRecognizedNodeClass(Class nodeClass) {
return Document.class.isAssignableFrom(nodeClass) ||
Element.class.isAssignableFrom(nodeClass) ||
Attribute.class.isAssignableFrom(nodeClass) ||
Text.class.isAssignableFrom(nodeClass) ||
CDATA.class.isAssignableFrom(nodeClass) ||
Comment.class.isAssignableFrom(nodeClass) ||
ProcessingInstruction.class.isAssignableFrom(nodeClass) ||
Namespace.class.isAssignableFrom(nodeClass);
}
/**
* 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.
* @return always null
*/
@Override
public Receiver getDocumentBuilder(Result result) {
return null;
}
/**
* 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
*/
@Override
public NodeInfo unravel(Source source, Configuration config) {
return null;
}
/**
* 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
*
* @param object the object to be converted . If this is not a JDOM node, the method returns null
* @param config the Saxon Configuration
* @return either an XPath node that wraps the supplied JDOM node, or null
*/
/*@Nullable*/
private GroundedValue convertObjectToXPathValue(Object object, Configuration config) {
if (isRecognizedNode(object)) {
if (object instanceof Document) {
return wrapDocument(object, config).getRootNode();
} else {
Document root = getDocumentRoot(object);
TreeInfo docInfo = wrapDocument(root, config);
return wrapNode(docInfo, object);
}
} else {
return null;
}
}
/**
* 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.
*
* @param value the XPath value to be converted
* @param target the Java class required for the result of the conversion
* @return the object that results from conversion if conversion is possible, or null otherwise
*/
/*@Nullable*/
private Object convertXPathValueToObject(Sequence value, Class target) {
if (value instanceof VirtualNode) {
Object u = ((VirtualNode) value).getRealNode();
if (target.isAssignableFrom(u.getClass())) {
return u;
}
}
return null;
}
/**
* Wrap a document node in the external object model in a document wrapper that implements
* the Saxon DocumentInfo interface
*
* @param node a node (any node) in the third party document
* @param config the Saxon configuration (which among other things provides access to the NamePool)
* @return the wrapper, which must implement DocumentInfo
*/
public TreeInfo wrapDocument(Object node, Configuration config) {
Document documentNode = getDocumentRoot(node);
return new JDOM2DocumentWrapper(documentNode, config);
}
/**
* Wrap a node within the external object model in a node wrapper that implements the Saxon
* VirtualNode interface (which is an extension of NodeInfo)
*
* @param document the document wrapper, as a DocumentInfo object
* @param node the node to be wrapped. This must be a node within the document wrapped by the
* DocumentInfo provided in the first argument
* @return the wrapper for the node, as an instance of VirtualNode
*/
public NodeInfo wrapNode(TreeInfo document, Object node) {
return ((JDOM2DocumentWrapper) document).wrap(node);
}
/**
* Get the document root
*
* @param node a JDOM node
* @return the root of the JDOM tree containing the given node
*/
private static Document getDocumentRoot(Object node) {
while (!(node instanceof Document)) {
if (node instanceof Element) {
if (((Element) node).isRootElement()) {
return ((Element) node).getDocument();
} else {
node = ((Element) node).getParent();
}
} else if (node instanceof Text) {
node = ((Text) node).getParent();
} else if (node instanceof Comment) {
node = ((Comment) node).getParent();
} else if (node instanceof ProcessingInstruction) {
node = ((ProcessingInstruction) node).getParent();
} else if (node instanceof Attribute) {
node = ((Attribute) node).getParent();
} else if (node instanceof Namespace) {
throw new UnsupportedOperationException("Cannot find parent of JDOM namespace node");
} else {
throw new IllegalStateException("Unknown JDOM node type " + node.getClass());
}
}
return (Document) node;
}
}
// Original Code is Copyright (c) 2009-2020 Saxonica Limited