/*
* eXist Open Source Native XML Database
* Copyright (C) 2001-2014 The eXist-db project
* wolfgang@exist-db.org
* http://exist.sourceforge.net
*
* 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 program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* $Id$
*/
package org.exist.dom.memtree;
import org.exist.dom.INodeHandle;
import org.exist.dom.QName;
import org.exist.dom.persistent.NodeProxy;
import org.exist.util.serializer.AttrList;
import org.exist.util.serializer.Receiver;
import org.exist.xquery.XQueryContext;
import org.w3c.dom.DOMException;
import org.w3c.dom.Document;
import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;
import org.xml.sax.ext.LexicalHandler;
import javax.xml.XMLConstants;
import java.util.Map;
import java.util.HashMap;
/**
* Builds an in-memory DOM tree from SAX {@link org.exist.util.serializer.Receiver} events.
*
* @author Wolfgang <wolfgang@exist-db.org>
*/
public class DocumentBuilderReceiver implements ContentHandler, LexicalHandler, Receiver {
private MemTreeBuilder builder = null;
private final boolean explicitNSDecl;
private Map<String, String> namespaces = null;
private boolean checkNS = false;
private boolean suppressWhitespace = true;
public DocumentBuilderReceiver() {
this(null);
}
public DocumentBuilderReceiver(final MemTreeBuilder builder) {
this(builder, false);
}
public DocumentBuilderReceiver(final MemTreeBuilder builder, final boolean declareNamespaces) {
this.builder = builder;
this.explicitNSDecl = declareNamespaces;
}
public void setCheckNS(final boolean checkNS) {
this.checkNS = checkNS;
}
public void setSuppressWhitespace(boolean flag) {
this.suppressWhitespace = flag;
}
@Override
public Document getDocument() {
return builder.getDocument();
}
public XQueryContext getContext() {
return builder.getContext();
}
@Override
public void setDocumentLocator(Locator locator) {
}
@Override
public void startDocument() throws SAXException {
if(builder == null) {
builder = new MemTreeBuilder();
builder.startDocument();
}
}
@Override
public void endDocument() throws SAXException {
builder.endDocument();
}
@Override
public void startPrefixMapping(final String prefix, final String namespaceURI) throws SAXException {
if(prefix == null || prefix.length() == 0) {
builder.setDefaultNamespace(namespaceURI);
}
if(!explicitNSDecl) {
return;
}
if(namespaces == null) {
namespaces = new HashMap<>();
}
namespaces.put(prefix, namespaceURI);
}
@Override
public void endPrefixMapping(final String prefix) throws SAXException {
if(prefix == null || prefix.length() == 0) {
builder.setDefaultNamespace(XMLConstants.NULL_NS_URI);
}
}
@Override
public void startElement(final String namespaceURI, final String localName, final String qName,
final Attributes attrs) throws SAXException {
builder.startElement(namespaceURI, localName, qName, attrs);
declareNamespaces();
}
private void declareNamespaces() {
if(explicitNSDecl && namespaces != null) {
for(final Map.Entry<String, String> entry : namespaces.entrySet()) {
builder.namespaceNode(entry.getKey(), entry.getValue());
}
namespaces.clear();
}
}
@Override
public void startElement(final QName qname, final AttrList attribs) {
builder.startElement(checkNS(true, qname), null);
declareNamespaces();
if(attribs != null) {
for(int i = 0; i < attribs.getLength(); i++) {
builder.addAttribute(attribs.getQName(i), attribs.getValue(i));
}
}
}
@Override
public void endElement(final String namespaceURI, final String localName, final String qName) throws SAXException {
builder.endElement();
}
@Override
public void endElement(final QName qname) throws SAXException {
builder.endElement();
}
public void addReferenceNode(final NodeProxy proxy) throws SAXException {
builder.addReferenceNode(proxy);
}
public void addNamespaceNode(final QName qname) throws SAXException {
builder.namespaceNode(qname, checkNS);
}
@Override
public void characters(final CharSequence seq) throws SAXException {
builder.characters(seq);
}
@Override
public void characters(final char[] ch, final int start, final int len) throws SAXException {
builder.characters(ch, start, len);
}
@Override
public void attribute(final QName qname, final String value) throws SAXException {
try {
builder.addAttribute(checkNS(false, qname), value);
} catch(final DOMException e) {
throw new SAXException(e.getMessage(), e);
}
}
@Override
public void ignorableWhitespace(final char[] ch, final int start, final int len) throws SAXException {
if (!suppressWhitespace) {
builder.characters(ch, start, len);
}
}
@Override
public void processingInstruction(final String target, final String data) throws SAXException {
builder.processingInstruction(target, data);
}
@Override
public void cdataSection(final char[] ch, final int start, final int len) throws SAXException {
builder.cdataSection(new String(ch, start, len));
}
@Override
public void skippedEntity(final String name) throws SAXException {
}
@Override
public void endCDATA() throws SAXException {
}
@Override
public void endDTD() throws SAXException {
}
@Override
public void startCDATA() throws SAXException {
}
@Override
public void documentType(final String name, final String publicId, final String systemId) throws SAXException {
builder.documentType(name, publicId, systemId);
}
@Override
public void comment(final char[] ch, final int start, final int length) throws SAXException {
builder.comment(ch, start, length);
}
@Override
public void endEntity(final String name) throws SAXException {
}
@Override
public void startEntity(final String name) throws SAXException {
}
@Override
public void startDTD(final String name, final String publicId, final String systemId) throws SAXException {
}
@Override
public void highlightText(final CharSequence seq) {
// not supported with this receiver
}
@Override
public void setCurrentNode(final INodeHandle node) {
// ignored
}
private QName checkNS(boolean isElement, final QName qname) {
if(checkNS) {
final XQueryContext context = builder.getContext();
if(qname.getPrefix() == null) {
if(!qname.hasNamespace()) {
return qname;
} else if(isElement) {
return qname;
} else {
final String prefix = generatePrefix(context, context.getInScopePrefix(qname.getNamespaceURI()));
context.declareInScopeNamespace(prefix, qname.getNamespaceURI());
return new QName(qname.getLocalPart(), qname.getNamespaceURI(), prefix);
}
}
if(qname.getPrefix().isEmpty() && qname.getNamespaceURI() == null) {
return qname;
}
final String inScopeNamespace = context.getInScopeNamespace(qname.getPrefix());
if(inScopeNamespace == null) {
context.declareInScopeNamespace(qname.getPrefix(), qname.getNamespaceURI());
} else if(!inScopeNamespace.equals(qname.getNamespaceURI())) {
final String prefix = generatePrefix(context, context.getInScopePrefix(qname.getNamespaceURI()));
context.declareInScopeNamespace(prefix, qname.getNamespaceURI());
return new QName(qname.getLocalPart(), qname.getNamespaceURI(), prefix);
}
}
return qname;
}
private String generatePrefix(final XQueryContext context, String prefix) {
int i = 0;
while(prefix == null) {
prefix = "XXX";
if(i > 0) {
prefix += String.valueOf(i);
}
if(context.getInScopeNamespace(prefix) != null) {
prefix = null;
i++;
}
}
return prefix;
}
}