DOMScanner.java
/*
* Copyright (c) 1997, 2022 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Distribution License v. 1.0, which is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
package org.glassfish.jaxb.core.unmarshaller;
import java.util.Enumeration;
import jakarta.xml.bind.ValidationEventLocator;
import jakarta.xml.bind.helpers.AbstractUnmarshallerImpl;
import jakarta.xml.bind.helpers.ValidationEventLocatorImpl;
import org.glassfish.jaxb.core.v2.runtime.unmarshaller.LocatorEx;
import org.w3c.dom.Attr;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.ProcessingInstruction;
import org.xml.sax.ContentHandler;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.AttributesImpl;
import org.xml.sax.helpers.NamespaceSupport;
/**
* Visits a W3C DOM tree and generates SAX2 events from it.
*
* <p>
* This class is just intended to be used by {@link AbstractUnmarshallerImpl}.
* The jakarta.xml.bind.helpers package is generally a wrong place to put
* classes like this.
*
* @author <ul><li>Kohsuke Kawaguchi, Sun Microsystems, Inc.</li></ul>
* @since JAXB 1.0
*/
public class DOMScanner implements LocatorEx,InfosetScanner<Node> {
/** reference to the current node being scanned - used for determining
* location info for validation events */
private Node currentNode = null;
/** To save memory, only one instance of AttributesImpl will be used. */
private final AttributesImpl atts = new AttributesImpl();
/** This handler will receive SAX2 events. */
private ContentHandler receiver=null;
private Locator locator=this;
public DOMScanner() {
}
/**
* Configures the locator object that the SAX {@link ContentHandler} will see.
*/
public void setLocator( Locator loc ) {
this.locator = loc;
}
@Override
public void scan(Node node) throws SAXException {
if( node instanceof Document ) {
scan( (Document)node );
} else {
scan( (Element)node );
}
}
public void scan( Document doc ) throws SAXException {
scan( doc.getDocumentElement() );
}
public void scan( Element e) throws SAXException {
setCurrentLocation( e );
receiver.setDocumentLocator(locator);
receiver.startDocument();
NamespaceSupport nss = new NamespaceSupport();
buildNamespaceSupport( nss, e.getParentNode() );
for( Enumeration<String> en = nss.getPrefixes(); en.hasMoreElements(); ) {
String prefix = en.nextElement();
receiver.startPrefixMapping( prefix, nss.getURI(prefix) );
}
final String defaultUri = nss.getURI("");
if (defaultUri != null && !defaultUri.isEmpty()) {
receiver.startPrefixMapping("", defaultUri);
}
visit(e);
for( Enumeration<String> en = nss.getPrefixes(); en.hasMoreElements(); ) {
String prefix = en.nextElement();
receiver.endPrefixMapping( prefix );
}
if (defaultUri != null && !defaultUri.isEmpty()) {
receiver.endPrefixMapping("");
}
setCurrentLocation( e );
receiver.endDocument();
}
/**
* Parses a subtree starting from the element e and
* reports SAX2 events to the specified handler.
*
* @deprecated in JAXB 2.0
* Use {@link #scan(Element)}
*/
@Deprecated(since="2.0", forRemoval=true)
public void parse( Element e, ContentHandler handler ) throws SAXException {
// it might be better to set receiver at the constructor.
receiver = handler;
setCurrentLocation( e );
receiver.startDocument();
receiver.setDocumentLocator(locator);
visit(e);
setCurrentLocation( e );
receiver.endDocument();
}
/**
* Similar to the parse method but it visits the ancestor nodes
* and properly emulate the all in-scope namespace declarations.
*
* @deprecated in JAXB 2.0
* Use {@link #scan(Element)}
*/
@Deprecated(since="2.0", forRemoval=true)
public void parseWithContext( Element e, ContentHandler handler ) throws SAXException {
setContentHandler(handler);
scan(e);
}
/**
* Recursively visit ancestors and build up {@link NamespaceSupport} oject.
*/
private void buildNamespaceSupport(NamespaceSupport nss, Node node) {
if(node==null || node.getNodeType()!=Node.ELEMENT_NODE)
return;
buildNamespaceSupport( nss, node.getParentNode() );
nss.pushContext();
NamedNodeMap atts = node.getAttributes();
for( int i=0; i<atts.getLength(); i++ ) {
Attr a = (Attr)atts.item(i);
if( "xmlns".equals(a.getPrefix()) ) {
nss.declarePrefix( a.getLocalName(), a.getValue() );
continue;
}
if( "xmlns".equals(a.getName()) ) {
nss.declarePrefix( "", a.getValue() );
continue;
}
}
}
/**
* Visits an element and its subtree.
*/
public void visit( Element e ) throws SAXException {
setCurrentLocation( e );
final NamedNodeMap attributes = e.getAttributes();
atts.clear();
int len = attributes==null ? 0: attributes.getLength();
for( int i=len-1; i>=0; i-- ) {
Attr a = (Attr)attributes.item(i);
String name = a.getName();
// start namespace binding
if(name.startsWith("xmlns")) {
if(name.length()==5) {
receiver.startPrefixMapping( "", a.getValue() );
} else {
String localName = a.getLocalName();
if(localName==null) {
// DOM built without namespace support has this problem
localName = name.substring(6);
}
receiver.startPrefixMapping( localName, a.getValue() );
}
continue;
}
String uri = a.getNamespaceURI();
if(uri==null) uri="";
String local = a.getLocalName();
if(local==null) local = a.getName();
// add other attributes to the attribute list
// that we will pass to the ContentHandler
atts.addAttribute(
uri,
local,
a.getName(),
"CDATA",
a.getValue());
}
String uri = e.getNamespaceURI();
if(uri==null) uri="";
String local = e.getLocalName();
String qname = e.getTagName();
if(local==null) local = qname;
receiver.startElement( uri, local, qname, atts );
// visit its children
NodeList children = e.getChildNodes();
int clen = children.getLength();
for( int i=0; i<clen; i++ )
visit(children.item(i));
setCurrentLocation( e );
receiver.endElement( uri, local, qname );
// call the endPrefixMapping method
for( int i=len-1; i>=0; i-- ) {
Attr a = (Attr)attributes.item(i);
String name = a.getName();
if(name.startsWith("xmlns")) {
if(name.length()==5)
receiver.endPrefixMapping("");
else
receiver.endPrefixMapping(a.getLocalName());
}
}
}
private void visit( Node n ) throws SAXException {
setCurrentLocation( n );
// if a case statement gets too big, it should be made into a separate method.
switch(n.getNodeType()) {
case Node.CDATA_SECTION_NODE:
case Node.TEXT_NODE:
String value = n.getNodeValue();
receiver.characters( value.toCharArray(), 0, value.length() );
break;
case Node.ELEMENT_NODE:
visit( (Element)n );
break;
case Node.ENTITY_REFERENCE_NODE:
receiver.skippedEntity(n.getNodeName());
break;
case Node.PROCESSING_INSTRUCTION_NODE:
ProcessingInstruction pi = (ProcessingInstruction)n;
receiver.processingInstruction(pi.getTarget(),pi.getData());
break;
}
}
private void setCurrentLocation( Node currNode ) {
currentNode = currNode;
}
/**
* The same as {@link #getCurrentElement()} but
* better typed.
*/
public Node getCurrentLocation() {
return currentNode;
}
@Override
public Node getCurrentElement() {
return currentNode;
}
@Override
public LocatorEx getLocator() {
return this;
}
@Override
public void setContentHandler(ContentHandler handler) {
this.receiver = handler;
}
@Override
public ContentHandler getContentHandler() {
return this.receiver;
}
// LocatorEx implementation
@Override
public String getPublicId() { return null; }
@Override
public String getSystemId() { return null; }
@Override
public int getLineNumber() { return -1; }
@Override
public int getColumnNumber() { return -1; }
@Override
public ValidationEventLocator getLocation() {
return new ValidationEventLocatorImpl(getCurrentLocation());
}
}