/*
* eXist Open Source Native XML Database
* Copyright (C) 2001-10 The eXist-db Project
* http://exist-db.org
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* $Id: Marshaller.java 14553 2011-05-27 13:26:09Z wolfgang_m $
*/
package org.exist.xqj;
import org.exist.xquery.value.*;
import org.exist.xquery.XPathException;
import org.exist.xquery.NameTest;
import org.exist.storage.DBBroker;
import org.exist.memtree.MemTreeBuilder;
import org.exist.memtree.NodeImpl;
import org.exist.memtree.InMemoryNodeSet;
import org.exist.memtree.ElementImpl;
import org.exist.memtree.DocumentBuilderReceiver;
import org.exist.dom.QName;
import org.w3c.dom.Node;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.AttributesImpl;
import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.XMLStreamReader;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamConstants;
import javax.xml.transform.dom.DOMSource;
import javax.xml.xquery.XQItemType;
import javax.xml.xquery.XQException;
import java.util.Properties;
import java.io.Reader;
import java.io.StringReader;
/**
* A utility class that provides marshalling services for external variables and methods
* to create DOM Nodes from streamed representation.
*
* @author Wolfgang Meier
*
*/
public class Marshaller {
public final static String NAMESPACE = "http://exist-db.org/xquery/types/serialized";
public final static String PREFIX = "sx";
private final static Properties OUTPUT_PROPERTIES = new Properties();
private final static String VALUE_ELEMENT = "value";
private final static String VALUE_ELEMENT_QNAME = PREFIX + ":value";
private final static QName VALUE_QNAME = new QName(VALUE_ELEMENT, NAMESPACE, PREFIX);
private final static String SEQ_ELEMENT = "sequence";
private final static String SEQ_ELEMENT_QNAME = PREFIX + ":sequence";
private final static String ATTR_TYPE = "type";
private final static String ATTR_ITEM_TYPE = "item-type";
public final static QName ROOT_ELEMENT_QNAME = new QName(SEQ_ELEMENT, NAMESPACE, PREFIX);
/**
* Marshall a sequence in an xml based string representation
* @param broker
* @param seq Sequence to be marshalled
* @param handler Content handler for building the resulting string
* @throws XPathException
* @throws SAXException
*/
public static void marshall(DBBroker broker, Sequence seq, ContentHandler handler) throws XPathException, SAXException {
AttributesImpl attrs = new AttributesImpl();
attrs.addAttribute("", ATTR_ITEM_TYPE, ATTR_ITEM_TYPE, "CDATA", Type.getTypeName(seq.getItemType()));
handler.startElement(NAMESPACE, SEQ_ELEMENT, SEQ_ELEMENT_QNAME, attrs);
for (SequenceIterator i = seq.iterate(); i.hasNext(); ) {
marshallItem(broker, i.nextItem(), handler);
}
handler.endElement(NAMESPACE, SEQ_ELEMENT, SEQ_ELEMENT_QNAME);
}
/**
* Marshall the items of a sequence in an xml based string representation
* @param broker
* @param seq Sequence which items are to be marshalled
* @param start index of first item to be marshalled
* @param howmany number of items following and including the first to be marshalled
* @param handler
* @throws XPathException
* @throws SAXException
*/
public static void marshall(DBBroker broker, Sequence seq,int start,int howmany, ContentHandler handler) throws XPathException, SAXException {
AttributesImpl attrs = new AttributesImpl();
attrs.addAttribute("", ATTR_ITEM_TYPE, ATTR_ITEM_TYPE, "CDATA", Type.getTypeName(seq.getItemType()));
handler.startElement(NAMESPACE, SEQ_ELEMENT, SEQ_ELEMENT_QNAME, attrs);
for (int i = start; i < howmany && i < seq.getItemCount(); i++ ) {
marshallItem(broker, seq.itemAt(i), handler);
}
handler.endElement(NAMESPACE, SEQ_ELEMENT, SEQ_ELEMENT_QNAME);
}
/**
* Marshall an item in an xml based string representation
* @param broker
* @param item Sequence(or Item) to me marshalled
* @param handler
* @throws SAXException
* @throws XPathException
*/
public static void marshallItem(DBBroker broker, Item item, ContentHandler handler) throws SAXException, XPathException {
AttributesImpl attrs = new AttributesImpl();
int type = item.getType();
if (type == Type.NODE)
type = ((NodeValue)item).getNode().getNodeType();
attrs.addAttribute("", ATTR_TYPE, ATTR_TYPE, "CDATA", Type.getTypeName(type));
if (Type.subTypeOf(item.getType(), Type.NODE)) {
handler.startElement(NAMESPACE, VALUE_ELEMENT, VALUE_ELEMENT_QNAME, attrs);
NodeValue nv = (NodeValue) item;
nv.toSAX(broker, handler, OUTPUT_PROPERTIES);
handler.endElement(NAMESPACE, VALUE_ELEMENT, VALUE_ELEMENT_QNAME);
} else {
handler.startElement(NAMESPACE, VALUE_ELEMENT, VALUE_ELEMENT_QNAME, attrs);
String value = item.getStringValue();
handler.characters(value.toCharArray(), 0, value.length());
handler.endElement(NAMESPACE, VALUE_ELEMENT, VALUE_ELEMENT_QNAME);
}
}
public static Sequence demarshall(DBBroker broker, Reader reader) throws XMLStreamException, XPathException {
XMLInputFactory factory = XMLInputFactory.newInstance();
factory.setProperty(XMLInputFactory.IS_NAMESPACE_AWARE, Boolean.TRUE);
factory.setProperty(XMLInputFactory.IS_VALIDATING, Boolean.FALSE);
XMLStreamReader parser = factory.createXMLStreamReader(reader);
return demarshall(broker, parser);
}
public static Sequence demarshall(DBBroker broker,Node n) throws XMLStreamException, XPathException {
DOMSource source = new DOMSource(n, null);
XMLInputFactory factory = XMLInputFactory.newInstance();
factory.setProperty(XMLInputFactory.IS_NAMESPACE_AWARE, Boolean.TRUE);
factory.setProperty(XMLInputFactory.IS_VALIDATING, Boolean.FALSE);
XMLStreamReader parser = factory.createXMLStreamReader(source);
return demarshall(broker,parser);
}
public static Sequence demarshall(DBBroker broker, XMLStreamReader parser) throws XMLStreamException, XPathException {
int event = parser.next();
while (event != XMLStreamConstants.START_ELEMENT)
event = parser.next();
if (!NAMESPACE.equals(parser.getNamespaceURI()))
throw new XMLStreamException("Root element is not in the correct namespace. Expected: " + NAMESPACE);
if (!SEQ_ELEMENT.equals(parser.getLocalName()))
throw new XMLStreamException("Root element should be a " + SEQ_ELEMENT_QNAME);
ValueSequence result = new ValueSequence();
while ((event = parser.next()) != XMLStreamConstants.END_DOCUMENT) {
switch (event) {
case XMLStreamConstants.START_ELEMENT :
if (NAMESPACE.equals(parser.getNamespaceURI()) && VALUE_ELEMENT.equals(parser.getLocalName())) {
String typeName = null;
// scan through attributes instead of direct lookup to work around issue in xerces
for (int i = 0; i < parser.getAttributeCount(); i++) {
if (ATTR_TYPE.equals(parser.getAttributeLocalName(i))) {
typeName = parser.getAttributeValue(i);
break;
}
}
if (typeName != null) {
int type = Type.getType(typeName);
Item item;
if (Type.subTypeOf(type, Type.NODE))
item = streamToDOM(type, parser);
else
item = new StringValue(parser.getElementText()).convertTo(type);
result.add(item);
}
}
break;
case XMLStreamConstants.END_ELEMENT :
if (NAMESPACE.equals(parser.getNamespaceURI()) && SEQ_ELEMENT.equals(parser.getLocalName()))
return result;
break;
}
}
return result;
}
public static Sequence demarshall(NodeImpl node) throws XMLStreamException, XPathException {
if (!NAMESPACE.equals(node.getNamespaceURI()))
throw new XMLStreamException("Root element is not in the correct namespace. Expected: " + NAMESPACE);
if (!SEQ_ELEMENT.equals(node.getLocalName()))
throw new XMLStreamException("Root element should be a " + SEQ_ELEMENT_QNAME);
ValueSequence result = new ValueSequence();
InMemoryNodeSet values = new InMemoryNodeSet();
node.selectChildren(new NameTest(Type.ELEMENT, VALUE_QNAME), values);
for (SequenceIterator i = values.iterate(); i.hasNext();) {
ElementImpl child = (ElementImpl) i.nextItem();
String typeName = child.getAttribute(ATTR_TYPE);
if (typeName != null) {
int type = Type.getType(typeName);
Item item;
if (Type.subTypeOf(type, Type.NODE)) {
item = (Item) child.getFirstChild();
if (type == Type.DOCUMENT) {
NodeImpl n = (NodeImpl) item;
DocumentBuilderReceiver receiver = new DocumentBuilderReceiver();
try {
receiver.startDocument();
n.getDocument().copyTo(n, receiver);
receiver.endDocument();
} catch (SAXException e) {
throw new XPathException("Error while demarshalling node: " + e.getMessage(), e);
}
item = (Item) receiver.getDocument();
}
} else {
StringBuilder data = new StringBuilder();
Node txt = child.getFirstChild();
while (txt != null) {
if (!(txt.getNodeType() == Node.TEXT_NODE || txt.getNodeType() == Node.CDATA_SECTION_NODE))
throw new XMLStreamException("sx:value should only contain text if type is " + typeName);
data.append(txt.getNodeValue());
txt = txt.getNextSibling();
}
item = new StringValue(data.toString()).convertTo(type);
}
result.add(item);
}
}
return result;
}
public static Item streamToDOM(XMLStreamReader parser, XQItemType type) throws XMLStreamException, XQException {
if (type.getBaseType() == XQItemType.XQITEMKIND_DOCUMENT_ELEMENT ||
type.getBaseType() == XQItemType.XQITEMKIND_DOCUMENT_SCHEMA_ELEMENT)
return streamToDOM(Type.DOCUMENT, parser);
else
return streamToDOM(Type.ELEMENT, parser);
}
/**
* Creates an Item from a streamed representation
* @param parser Parser to read xml elements from
* @return item
* @throws XMLStreamException
*/
public static Item streamToDOM(int rootType, XMLStreamReader parser) throws XMLStreamException {
MemTreeBuilder builder = new MemTreeBuilder();
builder.startDocument();
int event;
boolean finish = false;
while ((event = parser.next()) != XMLStreamConstants.END_DOCUMENT) {
switch (event) {
case XMLStreamConstants.START_ELEMENT :
AttributesImpl attribs = new AttributesImpl();
for (int i = 0; i < parser.getAttributeCount(); i++) {
javax.xml.namespace.QName qn = parser.getAttributeName(i);
attribs.addAttribute(qn.getNamespaceURI(), qn.getLocalPart(), qn.getPrefix() + ':' + qn.getLocalPart(),
parser.getAttributeType(i), parser.getAttributeValue(i));
}
builder.startElement(QName.fromJavaQName(parser.getName()), attribs);
// for (int i = 0; i < parser.getNamespaceCount(); i++) {
// builder.namespaceNode(parser.getNamespacePrefix(i), parser.getNamespaceURI(i));
// }
break;
case XMLStreamConstants.END_ELEMENT :
if (NAMESPACE.equals(parser.getNamespaceURI()) && VALUE_ELEMENT.equals(parser.getLocalName()))
finish = true;
else
builder.endElement();
break;
case XMLStreamConstants.CHARACTERS :
builder.characters(parser.getText());
break;
}
if (finish) break;
}
builder.endDocument();
if (rootType == Type.DOCUMENT)
return builder.getDocument();
else if (rootType == Type.ELEMENT)
return (NodeImpl) builder.getDocument().getDocumentElement();
else
return (NodeImpl) builder.getDocument().getFirstChild();
}
/**
* Creates an Item from a streamed representation
* @param reader
* @return item
* @throws XMLStreamException
*/
public static Item streamToDOM(Reader reader, XQItemType type) throws XMLStreamException, XQException {
XMLInputFactory factory = XMLInputFactory.newInstance();
factory.setProperty(XMLInputFactory.IS_NAMESPACE_AWARE, Boolean.TRUE);
factory.setProperty(XMLInputFactory.IS_VALIDATING, Boolean.FALSE);
XMLStreamReader parser = factory.createXMLStreamReader(reader);
return streamToDOM(parser, type);
}
/**
* Creates a node from a string representation
* @param content
* @return node
* @throws XMLStreamException
*/
public static Node streamToNode(String content) throws XMLStreamException {
StringReader reader = new StringReader(content);
return streamToNode(reader);
}
/**
* Creates a node from a streamed representation
* @param reader
* @return item
* @throws XMLStreamException
*/
public static Node streamToNode(Reader reader) throws XMLStreamException {
XMLInputFactory factory = XMLInputFactory.newInstance();
factory.setProperty(XMLInputFactory.IS_NAMESPACE_AWARE, Boolean.TRUE);
factory.setProperty(XMLInputFactory.IS_VALIDATING, Boolean.FALSE);
XMLStreamReader parser = factory.createXMLStreamReader(reader);
MemTreeBuilder builder = new MemTreeBuilder();
builder.startDocument();
int event;
boolean finish = false;
while ((event = parser.next()) != XMLStreamConstants.END_DOCUMENT) {
switch (event) {
case XMLStreamConstants.START_ELEMENT :
AttributesImpl attribs = new AttributesImpl();
for (int i = 0; i < parser.getAttributeCount(); i++) {
javax.xml.namespace.QName qn = parser.getAttributeName(i);
attribs.addAttribute(qn.getNamespaceURI(), qn.getLocalPart(), qn.getPrefix() + ':' + qn.getLocalPart(),
parser.getAttributeType(i), parser.getAttributeValue(i));
}
builder.startElement(QName.fromJavaQName(parser.getName()), attribs);
// for (int i = 0; i < parser.getNamespaceCount(); i++) {
// builder.namespaceNode(parser.getNamespacePrefix(i), parser.getNamespaceURI(i));
// }
break;
case XMLStreamConstants.END_ELEMENT :
if (NAMESPACE.equals(parser.getNamespaceURI()) && VALUE_ELEMENT.equals(parser.getLocalName()))
finish = true;
else
builder.endElement();
break;
case XMLStreamConstants.CHARACTERS :
builder.characters(parser.getText());
break;
}
if (finish) break;
}
builder.endDocument();
return builder.getDocument().getDocumentElement();
}
}