org.apache.xml.utils.DOMBuilder Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* $Id: DOMBuilder.java 472634 2006-11-08 20:43:55Z jycli $
*/
package org.apache.xml.utils;
import java.util.Stack;
import java.util.Vector;
import org.apache.xml.res.XMLErrorResources;
import org.apache.xml.res.XMLMessages;
import org.w3c.dom.Document;
import org.w3c.dom.DocumentFragment;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.Text;
import org.w3c.dom.CDATASection;
import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.Locator;
import org.xml.sax.ext.LexicalHandler;
/**
* This class takes SAX events (in addition to some extra events
* that SAX doesn't handle yet) and adds the result to a document
* or document fragment.
* @xsl.usage general
*/
public class DOMBuilder
implements ContentHandler, LexicalHandler
{
/** Root document */
public Document m_doc;
/** Current node */
protected Node m_currentNode = null;
/** The root node */
protected Node m_root = null;
/** The next sibling node */
protected Node m_nextSibling = null;
/** First node of document fragment or null if not a DocumentFragment */
public DocumentFragment m_docFrag = null;
/** Vector of element nodes */
protected Stack m_elemStack = new Stack();
/** Namespace support */
protected Vector m_prefixMappings = new Vector();
/**
* DOMBuilder instance constructor... it will add the DOM nodes
* to the document fragment.
*
* @param doc Root document
* @param node Current node
*/
public DOMBuilder(Document doc, Node node)
{
m_doc = doc;
m_currentNode = m_root = node;
if (node instanceof Element)
m_elemStack.push(node);
}
/**
* DOMBuilder instance constructor... it will add the DOM nodes
* to the document fragment.
*
* @param doc Root document
* @param docFrag Document fragment
*/
public DOMBuilder(Document doc, DocumentFragment docFrag)
{
m_doc = doc;
m_docFrag = docFrag;
}
/**
* DOMBuilder instance constructor... it will add the DOM nodes
* to the document.
*
* @param doc Root document
*/
public DOMBuilder(Document doc)
{
m_doc = doc;
}
/**
* Get the root document or DocumentFragment of the DOM being created.
*
* @return The root document or document fragment if not null
*/
public Node getRootDocument()
{
return (null != m_docFrag) ? (Node) m_docFrag : (Node) m_doc;
}
/**
* Get the root node of the DOM tree.
*/
public Node getRootNode()
{
return m_root;
}
/**
* Get the node currently being processed.
*
* @return the current node being processed
*/
public Node getCurrentNode()
{
return m_currentNode;
}
/**
* Set the next sibling node, which is where the result nodes
* should be inserted before.
*
* @param nextSibling the next sibling node.
*/
public void setNextSibling(Node nextSibling)
{
m_nextSibling = nextSibling;
}
/**
* Return the next sibling node.
*
* @return the next sibling node.
*/
public Node getNextSibling()
{
return m_nextSibling;
}
/**
* Return null since there is no Writer for this class.
*
* @return null
*/
public java.io.Writer getWriter()
{
return null;
}
/**
* Append a node to the current container.
*
* @param newNode New node to append
*/
protected void append(Node newNode) throws org.xml.sax.SAXException
{
Node currentNode = m_currentNode;
if (null != currentNode)
{
if (currentNode == m_root && m_nextSibling != null)
currentNode.insertBefore(newNode, m_nextSibling);
else
currentNode.appendChild(newNode);
// System.out.println(newNode.getNodeName());
}
else if (null != m_docFrag)
{
if (m_nextSibling != null)
m_docFrag.insertBefore(newNode, m_nextSibling);
else
m_docFrag.appendChild(newNode);
}
else
{
boolean ok = true;
short type = newNode.getNodeType();
if (type == Node.TEXT_NODE)
{
String data = newNode.getNodeValue();
if ((null != data) && (data.trim().length() > 0))
{
throw new org.xml.sax.SAXException(
XMLMessages.createXMLMessage(
XMLErrorResources.ER_CANT_OUTPUT_TEXT_BEFORE_DOC, null)); //"Warning: can't output text before document element! Ignoring...");
}
ok = false;
}
else if (type == Node.ELEMENT_NODE)
{
if (m_doc.getDocumentElement() != null)
{
ok = false;
throw new org.xml.sax.SAXException(
XMLMessages.createXMLMessage(
XMLErrorResources.ER_CANT_HAVE_MORE_THAN_ONE_ROOT, null)); //"Can't have more than one root on a DOM!");
}
}
if (ok)
{
if (m_nextSibling != null)
m_doc.insertBefore(newNode, m_nextSibling);
else
m_doc.appendChild(newNode);
}
}
}
/**
* Receive an object for locating the origin of SAX document events.
*
* SAX parsers are strongly encouraged (though not absolutely
* required) to supply a locator: if it does so, it must supply
* the locator to the application by invoking this method before
* invoking any of the other methods in the ContentHandler
* interface.
*
* The locator allows the application to determine the end
* position of any document-related event, even if the parser is
* not reporting an error. Typically, the application will
* use this information for reporting its own errors (such as
* character content that does not match an application's
* business rules). The information returned by the locator
* is probably not sufficient for use with a search engine.
*
* Note that the locator will return correct information only
* during the invocation of the events in this interface. The
* application should not attempt to use it at any other time.
*
* @param locator An object that can return the location of
* any SAX document event.
* @see org.xml.sax.Locator
*/
public void setDocumentLocator(Locator locator)
{
// No action for the moment.
}
/**
* Receive notification of the beginning of a document.
*
* The SAX parser will invoke this method only once, before any
* other methods in this interface or in DTDHandler (except for
* setDocumentLocator).
*/
public void startDocument() throws org.xml.sax.SAXException
{
// No action for the moment.
}
/**
* Receive notification of the end of a document.
*
* The SAX parser will invoke this method only once, and it will
* be the last method invoked during the parse. The parser shall
* not invoke this method until it has either abandoned parsing
* (because of an unrecoverable error) or reached the end of
* input.
*/
public void endDocument() throws org.xml.sax.SAXException
{
// No action for the moment.
}
/**
* Receive notification of the beginning of an element.
*
* The Parser will invoke this method at the beginning of every
* element in the XML document; there will be a corresponding
* endElement() event for every startElement() event (even when the
* element is empty). All of the element's content will be
* reported, in order, before the corresponding endElement()
* event.
*
* If the element name has a namespace prefix, the prefix will
* still be attached. Note that the attribute list provided will
* contain only attributes with explicit values (specified or
* defaulted): #IMPLIED attributes will be omitted.
*
*
* @param ns The namespace of the node
* @param localName The local part of the qualified name
* @param name The element name.
* @param atts The attributes attached to the element, if any.
* @see #endElement
* @see org.xml.sax.Attributes
*/
public void startElement(
String ns, String localName, String name, Attributes atts)
throws org.xml.sax.SAXException
{
Element elem;
// Note that the namespace-aware call must be used to correctly
// construct a Level 2 DOM, even for non-namespaced nodes.
if ((null == ns) || (ns.length() == 0))
elem = m_doc.createElementNS(null,name);
else
elem = m_doc.createElementNS(ns, name);
append(elem);
try
{
int nAtts = atts.getLength();
if (0 != nAtts)
{
for (int i = 0; i < nAtts; i++)
{
//System.out.println("type " + atts.getType(i) + " name " + atts.getLocalName(i) );
// First handle a possible ID attribute
if (atts.getType(i).equalsIgnoreCase("ID"))
setIDAttribute(atts.getValue(i), elem);
String attrNS = atts.getURI(i);
if("".equals(attrNS))
attrNS = null; // DOM represents no-namespace as null
// System.out.println("attrNS: "+attrNS+", localName: "+atts.getQName(i)
// +", qname: "+atts.getQName(i)+", value: "+atts.getValue(i));
// Crimson won't let us set an xmlns: attribute on the DOM.
String attrQName = atts.getQName(i);
// In SAX, xmlns[:] attributes have an empty namespace, while in DOM they
// should have the xmlns namespace
if (attrQName.startsWith("xmlns:") || attrQName.equals("xmlns")) {
attrNS = "http://www.w3.org/2000/xmlns/";
}
// ALWAYS use the DOM Level 2 call!
elem.setAttributeNS(attrNS,attrQName, atts.getValue(i));
}
}
/*
* Adding namespace nodes to the DOM tree;
*/
int nDecls = m_prefixMappings.size();
String prefix, declURL;
for (int i = 0; i < nDecls; i += 2)
{
prefix = (String) m_prefixMappings.elementAt(i);
if (prefix == null)
continue;
declURL = (String) m_prefixMappings.elementAt(i + 1);
elem.setAttributeNS("http://www.w3.org/2000/xmlns/", prefix, declURL);
}
m_prefixMappings.clear();
// append(elem);
m_elemStack.push(elem);
m_currentNode = elem;
// append(elem);
}
catch(java.lang.Exception de)
{
// de.printStackTrace();
throw new org.xml.sax.SAXException(de);
}
}
/**
* Receive notification of the end of an element.
*
* The SAX parser will invoke this method at the end of every
* element in the XML document; there will be a corresponding
* startElement() event for every endElement() event (even when the
* element is empty).
*
* If the element name has a namespace prefix, the prefix will
* still be attached to the name.
*
*
* @param ns the namespace of the element
* @param localName The local part of the qualified name of the element
* @param name The element name
*/
public void endElement(String ns, String localName, String name)
throws org.xml.sax.SAXException
{
m_elemStack.pop();
m_currentNode = m_elemStack.isEmpty() ? null : (Node)m_elemStack.peek();
}
/**
* Set an ID string to node association in the ID table.
*
* @param id The ID string.
* @param elem The associated ID.
*/
public void setIDAttribute(String id, Element elem)
{
// Do nothing. This method is meant to be overiden.
}
/**
* Receive notification of character data.
*
* The Parser will call this method to report each chunk of
* character data. SAX parsers may return all contiguous character
* data in a single chunk, or they may split it into several
* chunks; however, all of the characters in any single event
* must come from the same external entity, so that the Locator
* provides useful information.
*
* The application must not attempt to read from the array
* outside of the specified range.
*
* Note that some parsers will report whitespace using the
* ignorableWhitespace() method rather than this one (validating
* parsers must do so).
*
* @param ch The characters from the XML document.
* @param start The start position in the array.
* @param length The number of characters to read from the array.
* @see #ignorableWhitespace
* @see org.xml.sax.Locator
*/
public void characters(char ch[], int start, int length) throws org.xml.sax.SAXException
{
if(isOutsideDocElem()
&& org.apache.xml.utils.XMLCharacterRecognizer.isWhiteSpace(ch, start, length))
return; // avoid DOM006 Hierarchy request error
if (m_inCData)
{
cdata(ch, start, length);
return;
}
String s = new String(ch, start, length);
Node childNode;
childNode = m_currentNode != null ? m_currentNode.getLastChild(): null;
if( childNode != null && childNode.getNodeType() == Node.TEXT_NODE ){
((Text)childNode).appendData(s);
}
else{
Text text = m_doc.createTextNode(s);
append(text);
}
}
/**
* If available, when the disable-output-escaping attribute is used,
* output raw text without escaping. A PI will be inserted in front
* of the node with the name "lotusxsl-next-is-raw" and a value of
* "formatter-to-dom".
*
* @param ch Array containing the characters
* @param start Index to start of characters in the array
* @param length Number of characters in the array
*/
public void charactersRaw(char ch[], int start, int length)
throws org.xml.sax.SAXException
{
if(isOutsideDocElem()
&& org.apache.xml.utils.XMLCharacterRecognizer.isWhiteSpace(ch, start, length))
return; // avoid DOM006 Hierarchy request error
String s = new String(ch, start, length);
append(m_doc.createProcessingInstruction("xslt-next-is-raw",
"formatter-to-dom"));
append(m_doc.createTextNode(s));
}
/**
* Report the beginning of an entity.
*
* The start and end of the document entity are not reported.
* The start and end of the external DTD subset are reported
* using the pseudo-name "[dtd]". All other events must be
* properly nested within start/end entity events.
*
* @param name The name of the entity. If it is a parameter
* entity, the name will begin with '%'.
* @see #endEntity
* @see org.xml.sax.ext.DeclHandler#internalEntityDecl
* @see org.xml.sax.ext.DeclHandler#externalEntityDecl
*/
public void startEntity(String name) throws org.xml.sax.SAXException
{
// Almost certainly the wrong behavior...
// entityReference(name);
}
/**
* Report the end of an entity.
*
* @param name The name of the entity that is ending.
* @see #startEntity
*/
public void endEntity(String name) throws org.xml.sax.SAXException{}
/**
* Receive notivication of a entityReference.
*
* @param name name of the entity reference
*/
public void entityReference(String name) throws org.xml.sax.SAXException
{
append(m_doc.createEntityReference(name));
}
/**
* Receive notification of ignorable whitespace in element content.
*
* Validating Parsers must use this method to report each chunk
* of ignorable whitespace (see the W3C XML 1.0 recommendation,
* section 2.10): non-validating parsers may also use this method
* if they are capable of parsing and using content models.
*
* SAX parsers may return all contiguous whitespace in a single
* chunk, or they may split it into several chunks; however, all of
* the characters in any single event must come from the same
* external entity, so that the Locator provides useful
* information.
*
* The application must not attempt to read from the array
* outside of the specified range.
*
* @param ch The characters from the XML document.
* @param start The start position in the array.
* @param length The number of characters to read from the array.
* @see #characters
*/
public void ignorableWhitespace(char ch[], int start, int length)
throws org.xml.sax.SAXException
{
if(isOutsideDocElem())
return; // avoid DOM006 Hierarchy request error
String s = new String(ch, start, length);
append(m_doc.createTextNode(s));
}
/**
* Tell if the current node is outside the document element.
*
* @return true if the current node is outside the document element.
*/
private boolean isOutsideDocElem()
{
return (null == m_docFrag) && m_elemStack.size() == 0 && (null == m_currentNode || m_currentNode.getNodeType() == Node.DOCUMENT_NODE);
}
/**
* Receive notification of a processing instruction.
*
* The Parser will invoke this method once for each processing
* instruction found: note that processing instructions may occur
* before or after the main document element.
*
* A SAX parser should never report an XML declaration (XML 1.0,
* section 2.8) or a text declaration (XML 1.0, section 4.3.1)
* using this method.
*
* @param target The processing instruction target.
* @param data The processing instruction data, or null if
* none was supplied.
*/
public void processingInstruction(String target, String data)
throws org.xml.sax.SAXException
{
append(m_doc.createProcessingInstruction(target, data));
}
/**
* Report an XML comment anywhere in the document.
*
* This callback will be used for comments inside or outside the
* document element, including comments in the external DTD
* subset (if read).
*
* @param ch An array holding the characters in the comment.
* @param start The starting position in the array.
* @param length The number of characters to use from the array.
*/
public void comment(char ch[], int start, int length) throws org.xml.sax.SAXException
{
append(m_doc.createComment(new String(ch, start, length)));
}
/** Flag indicating that we are processing a CData section */
protected boolean m_inCData = false;
/**
* Report the start of a CDATA section.
*
* @see #endCDATA
*/
public void startCDATA() throws org.xml.sax.SAXException
{
m_inCData = true;
append(m_doc.createCDATASection(""));
}
/**
* Report the end of a CDATA section.
*
* @see #startCDATA
*/
public void endCDATA() throws org.xml.sax.SAXException
{
m_inCData = false;
}
/**
* Receive notification of cdata.
*
* The Parser will call this method to report each chunk of
* character data. SAX parsers may return all contiguous character
* data in a single chunk, or they may split it into several
* chunks; however, all of the characters in any single event
* must come from the same external entity, so that the Locator
* provides useful information.
*
* The application must not attempt to read from the array
* outside of the specified range.
*
* Note that some parsers will report whitespace using the
* ignorableWhitespace() method rather than this one (validating
* parsers must do so).
*
* @param ch The characters from the XML document.
* @param start The start position in the array.
* @param length The number of characters to read from the array.
* @see #ignorableWhitespace
* @see org.xml.sax.Locator
*/
public void cdata(char ch[], int start, int length) throws org.xml.sax.SAXException
{
if(isOutsideDocElem()
&& org.apache.xml.utils.XMLCharacterRecognizer.isWhiteSpace(ch, start, length))
return; // avoid DOM006 Hierarchy request error
String s = new String(ch, start, length);
CDATASection section =(CDATASection) m_currentNode.getLastChild();
section.appendData(s);
}
/**
* Report the start of DTD declarations, if any.
*
* Any declarations are assumed to be in the internal subset
* unless otherwise indicated.
*
* @param name The document type name.
* @param publicId The declared public identifier for the
* external DTD subset, or null if none was declared.
* @param systemId The declared system identifier for the
* external DTD subset, or null if none was declared.
* @see #endDTD
* @see #startEntity
*/
public void startDTD(String name, String publicId, String systemId)
throws org.xml.sax.SAXException
{
// Do nothing for now.
}
/**
* Report the end of DTD declarations.
*
* @see #startDTD
*/
public void endDTD() throws org.xml.sax.SAXException
{
// Do nothing for now.
}
/**
* Begin the scope of a prefix-URI Namespace mapping.
*
* The information from this event is not necessary for
* normal Namespace processing: the SAX XML reader will
* automatically replace prefixes for element and attribute
* names when the http://xml.org/sax/features/namespaces
* feature is true (the default).
*
* There are cases, however, when applications need to
* use prefixes in character data or in attribute values,
* where they cannot safely be expanded automatically; the
* start/endPrefixMapping event supplies the information
* to the application to expand prefixes in those contexts
* itself, if necessary.
*
* Note that start/endPrefixMapping events are not
* guaranteed to be properly nested relative to each-other:
* all startPrefixMapping events will occur before the
* corresponding startElement event, and all endPrefixMapping
* events will occur after the corresponding endElement event,
* but their order is not guaranteed.
*
* @param prefix The Namespace prefix being declared.
* @param uri The Namespace URI the prefix is mapped to.
* @see #endPrefixMapping
* @see #startElement
*/
public void startPrefixMapping(String prefix, String uri)
throws org.xml.sax.SAXException
{
if(null == prefix || prefix.equals(""))
prefix = "xmlns";
else prefix = "xmlns:"+prefix;
m_prefixMappings.addElement(prefix);
m_prefixMappings.addElement(uri);
}
/**
* End the scope of a prefix-URI mapping.
*
* See startPrefixMapping for details. This event will
* always occur after the corresponding endElement event,
* but the order of endPrefixMapping events is not otherwise
* guaranteed.
*
* @param prefix The prefix that was being mapping.
* @see #startPrefixMapping
* @see #endElement
*/
public void endPrefixMapping(String prefix) throws org.xml.sax.SAXException{}
/**
* Receive notification of a skipped entity.
*
* The Parser will invoke this method once for each entity
* skipped. Non-validating processors may skip entities if they
* have not seen the declarations (because, for example, the
* entity was declared in an external DTD subset). All processors
* may skip external entities, depending on the values of the
* http://xml.org/sax/features/external-general-entities and the
* http://xml.org/sax/features/external-parameter-entities
* properties.
*
* @param name The name of the skipped entity. If it is a
* parameter entity, the name will begin with '%'.
*/
public void skippedEntity(String name) throws org.xml.sax.SAXException{}
}