* The parsing methods in this class make use of some features internal to the * Xerces DOM parser, mainly for performance reasons. As soon as JAXP (currently * at version 1.2) is better at schema handling, it should be used as the parser * interface. *
* */ public class DomUtils { private static final Logger log = LoggerFactory.getLogger(DomUtils.class); /** Feature URI for namespace aware parsing. */ private static final String NAMESPACES_FEATURE = "http://xml.org/sax/features/namespaces"; /** Feature URI for validating parsing. */ private static final String VALIDATION_FEATURE = "http://xml.org/sax/features/validation"; /** Feature URI for schema validating parsing. */ private static final String SCHEMA_VALIDATION_FEATURE = "http://apache.org/xml/features/validation/schema"; /** Feature URI for normalization of element/attribute values. */ private static final String NORMALIZED_VALUE_FEATURE = "http://apache.org/xml/features/validation/schema/normalized-value"; /** Feature URI for parsing ignorable whitespace. */ private static final String INCLUDE_IGNORABLE_WHITESPACE_FEATURE = "http://apache.org/xml/features/dom/include-ignorable-whitespace"; /** Feature URI for creating EntityReference nodes in the DOM tree. */ private static final String CREATE_ENTITY_REF_NODES_FEATURE = "http://apache.org/xml/features/dom/create-entity-ref-nodes"; /** Property URI for providing external schema locations. */ private static final String EXTERNAL_SCHEMA_LOCATION_PROPERTY = "http://apache.org/xml/properties/schema/external-schemaLocation"; /** * Property URI for providing the external schema location for elements without * a namespace. */ private static final String EXTERNAL_NO_NAMESPACE_SCHEMA_LOCATION_PROPERTY = "http://apache.org/xml/properties/schema/external-noNamespaceSchemaLocation"; private static final String EXTERNAL_GENERAL_ENTITIES_FEATURE = "http://xml.org/sax/features/external-general-entities"; private static final String EXTERNAL_PARAMETER_ENTITIES_FEATURE = "http://xml.org/sax/features/external-parameter-entities"; public static final String DISALLOW_DOCTYPE_FEATURE = "http://apache.org/xml/features/disallow-doctype-decl"; /** Property URI for the Xerces grammar pool. */ private static final String GRAMMAR_POOL = org.apache.xerces.impl.Constants.XERCES_PROPERTY_PREFIX + org.apache.xerces.impl.Constants.XMLGRAMMAR_POOL_PROPERTY; /** A prime number for initializing the symbol table. */ private static final int BIG_PRIME = 2039; /** Symbol table for the grammar pool. */ private static SymbolTable symbolTable = new SymbolTable(BIG_PRIME); /** Xerces schema grammar pool. */ private static XMLGrammarPool grammarPool = new XMLGrammarPoolImpl(); /** * Set holding the NamespaceURIs of the grammarPool, to prevent multiple entries * of same grammars to the pool. */ private static Set grammarNamespaces; static { grammarPool.lockPool(); grammarNamespaces = new HashSet(); } /** * Preparse a schema and add it to the schema pool. The method only adds the * schema to the pool if a schema having the samesystemId
* (namespace URI) is not already present in the pool.
*
* @param inputStream An InputStream providing the contents of the
* schema.
* @param systemId The systemId (namespace URI) to use for the schema.
* @throws IOException An error occurred reading the schema.
*/
public static void addSchemaToPool(final InputStream inputStream, final String systemId)
throws IOException {
XMLGrammarPreparser preparser;
if (!grammarNamespaces.contains(systemId)) {
grammarNamespaces.add(systemId);
// unlock the pool so that we can add another grammar
grammarPool.unlockPool();
// prepare the preparser
preparser = new XMLGrammarPreparser(symbolTable);
preparser.registerPreparser(XMLGrammarDescription.XML_SCHEMA, null);
preparser.setProperty(GRAMMAR_POOL, grammarPool);
preparser.setFeature(NAMESPACES_FEATURE, true);
preparser.setFeature(VALIDATION_FEATURE, true);
// add the grammar to the pool
preparser.preparseGrammar(XMLGrammarDescription.XML_SCHEMA,
new XMLInputSource(null, systemId, null, inputStream, null));
// lock the pool again so that schemas are not added automatically
grammarPool.lockPool();
}
}
/**
* Parse an XML document from an InputStream.
*
*
* It uses a MOAEntityResolver as the EntityResolver
* and a MOAErrorHandler as the ErrorHandler.
*
InputStream
* containing the XML document.
* @param validating If true, parse
* validating.
* @param externalSchemaLocations A String containing
* namespace URI to schema location
* pairs, the same way it is accepted
* by the xsi:
* schemaLocation attribute.
* @param externalNoNamespaceSchemaLocation The schema location of the schema
* for elements without a namespace,
* the same way it is accepted by the
* xsi:noNamespaceSchemaLocation
* attribute.
* @param parserFeatures Map of features that should be set
* into XML parser
* @return The parsed XML document as a DOM tree.
* @throws SAXException An error occurred parsing the document.
* @throws IOException An error occurred reading the document.
* @throws ParserConfigurationException An error occurred configuring the XML
* parser.
*/
public static Document parseDocument(final InputStream inputStream, final boolean validating,
final String externalSchemaLocations, final String externalNoNamespaceSchemaLocation,
final MapString.
*
*
* It uses a MOAEntityResolver as the EntityResolver
* and a MOAErrorHandler as the ErrorHandler.
*
String containing
* the XML document.
* @param encoding The encoding of the XML document.
* @param validating If true, parse
* validating.
* @param externalSchemaLocations A String containing
* namespace URI to schema location
* pairs, the same way it is accepted
* by the xsi:
* schemaLocation attribute.
* @param externalNoNamespaceSchemaLocation The schema location of the schema
* for elements without a namespace,
* the same way it is accepted by the
* xsi:noNamespaceSchemaLocation
* attribute.
* @return The parsed XML document as a DOM tree.
* @throws SAXException An error occurred parsing the document.
* @throws IOException An error occurred reading the document.
* @throws ParserConfigurationException An error occurred configuring the XML
* parser.
*/
public static Document parseDocument(final String xmlString, final String encoding,
final boolean validating, final String externalSchemaLocations,
final String externalNoNamespaceSchemaLocation, final MapString.
*
*
* It uses a MOAEntityResolver as the EntityResolver
* and a MOAErrorHandler as the ErrorHandler.
*
String containing
* the XML document.
* @param encoding The encoding of the XML document.
* @param validating If true, parse
* validating.
* @param externalSchemaLocations A String containing
* namespace URI to schema location
* pairs, the same way it is accepted
* by the xsi:
* schemaLocation attribute.
* @param externalNoNamespaceSchemaLocation The schema location of the schema
* for elements without a namespace,
* the same way it is accepted by the
* xsi:noNamespaceSchemaLocation
* attribute.
* @return The parsed XML document as a DOM tree.
* @throws SAXException An error occurred parsing the document.
* @throws IOException An error occurred reading the document.
* @throws ParserConfigurationException An error occurred configuring the XML
* parser.
*/
public static Document parseDocument(final String xmlString, final String encoding,
final boolean validating, final String externalSchemaLocations,
final String externalNoNamespaceSchemaLocation)
throws SAXException, IOException, ParserConfigurationException {
final InputStream in = new ByteArrayInputStream(xmlString.getBytes(encoding));
return parseDocument(in, validating, externalSchemaLocations, externalNoNamespaceSchemaLocation,
null);
}
/**
* Parse an UTF-8 encoded XML document from a String.
*
* @param xmlString The String containing
* the XML document.
* @param validating If true, parse
* validating.
* @param externalSchemaLocations A String containing
* namespace URI to schema location
* pairs, the same way it is accepted
* by the xsi:
* schemaLocation attribute.
* @param externalNoNamespaceSchemaLocation The schema location of the schema
* for elements without a namespace,
* the same way it is accepted by the
* xsi:noNamespaceSchemaLocation
* attribute.
* @return The parsed XML document as a DOM tree.
* @throws SAXException An error occurred parsing the document.
* @throws IOException An error occurred reading the document.
* @throws ParserConfigurationException An error occurred configuring the XML
* parser.
*/
public static Document parseDocument(final String xmlString, final boolean validating,
final String externalSchemaLocations, final String externalNoNamespaceSchemaLocation)
throws SAXException, IOException, ParserConfigurationException {
return parseDocument(xmlString, "UTF-8", validating, externalSchemaLocations,
externalNoNamespaceSchemaLocation);
}
/**
* Parse an XML document from an InputStream.
*
* @param inputStream The InputStream
* containing the XML document.
* @param validating If true, parse
* validating.
* @param externalSchemaLocations A String containing
* namespace URI to schema location
* pairs, the same way it is accepted
* by the xsi:
* schemaLocation attribute.
* @param externalNoNamespaceSchemaLocation The schema location of the schema
* for elements without a namespace,
* the same way it is accepted by the
* xsi:noNamespaceSchemaLocation
* attribute.
* @param entityResolver An EntityResolver to
* resolve external entities (schemas
* and DTDs). If null, it
* will not be set.
* @param errorHandler An ErrorHandler to
* decide what to do with parsing
* errors. If null, it
* will not be set.
* @return The parsed XML document as a DOM tree.
* @throws SAXException An error occurred parsing the document.
* @throws IOException An error occurred reading the document.
* @throws ParserConfigurationException An error occurred configuring the XML
* parser.
*/
public static Document parseDocument(final InputStream inputStream, final boolean validating,
final String externalSchemaLocations, final String externalNoNamespaceSchemaLocation,
final EntityResolver entityResolver, final ErrorHandler errorHandler,
final MapInputStream containing the XML document.
* @return The root element of the parsed XML document.
* @throws SAXException An error occurred parsing the document.
* @throws IOException An error occurred reading the document.
* @throws ParserConfigurationException An error occurred configuring the XML
* parser.
*/
public static Element parseXmlValidating(final InputStream inputStream)
throws ParserConfigurationException, SAXException, IOException {
return DomUtils
.parseDocument(inputStream, true, XmlNamespaceConstants.ALL_SCHEMA_LOCATIONS, null, null)
.getDocumentElement();
}
/**
* A convenience method to parse an XML document validating.
*
* @param inputStream The InputStream containing the XML
* document.
* @param parserFeatures Set additional features to XML parser
* @return The root element of the parsed XML document.
* @throws SAXException An error occurred parsing the document.
* @throws IOException An error occurred reading the document.
* @throws ParserConfigurationException An error occurred configuring the XML
* parser.
*/
public static Element parseXmlValidating(final InputStream inputStream,
final MapInputStream containing the XML document.
* @return The root element of the parsed XML document.
* @throws SAXException An error occurred parsing the document.
* @throws IOException An error occurred reading the document.
* @throws ParserConfigurationException An error occurred configuring the XML
* parser.
*/
public static Element parseXmlNonValidating(final InputStream inputStream)
throws ParserConfigurationException, SAXException, IOException {
return DomUtils.parseDocument(inputStream, false, XmlNamespaceConstants.ALL_SCHEMA_LOCATIONS,
null, Collections.unmodifiableMap(new HashMapString containing
* namespace URI to schema location
* pairs, the same way it is accepted
* by the xsi:
* schemaLocation attribute.
* @param externalNoNamespaceSchemaLocation The schema location of the schema
* for elements without a namespace,
* the same way it is accepted by the
* xsi:noNamespaceSchemaLocation
* attribute.
* @return true, if the element validates against the
* schemas declared in it.
* @throws SAXException An error occurred parsing the document.
* @throws IOException An error occurred reading the document
* from its serialized representation.
* @throws ParserConfigurationException An error occurred configuring the XML
* @throws TransformerException An error occurred serializing the
* element.
*/
public static boolean validateElement(final Element element, final String externalSchemaLocations,
final String externalNoNamespaceSchemaLocation)
throws ParserConfigurationException, IOException, SAXException, TransformerException {
byte[] docBytes;
SAXParser parser;
// create the SAX parser
if (symbolTable != null) {
parser = new SAXParser(symbolTable, grammarPool);
} else {
parser = new SAXParser();
}
// serialize the document
docBytes = serializeNode(element, "UTF-8");
// set up parser features and attributes
parser.setFeature(NAMESPACES_FEATURE, true);
parser.setFeature(VALIDATION_FEATURE, true);
parser.setFeature(SCHEMA_VALIDATION_FEATURE, true);
parser.setFeature(EXTERNAL_GENERAL_ENTITIES_FEATURE, false);
parser.setFeature(DISALLOW_DOCTYPE_FEATURE, true);
if (externalSchemaLocations != null) {
parser.setProperty(EXTERNAL_SCHEMA_LOCATION_PROPERTY, externalSchemaLocations);
}
if (externalNoNamespaceSchemaLocation != null) {
parser.setProperty(EXTERNAL_NO_NAMESPACE_SCHEMA_LOCATION_PROPERTY,
"externalNoNamespaceSchemaLocation");
}
// set up entity resolver and error handler
parser.setEntityResolver(new EaafDomEntityResolver());
// parse validating
parser.parse(new InputSource(new ByteArrayInputStream(docBytes)));
return true;
}
/**
* Schema validate a given DOM element.
*
* @param element The element to validate.
* @param externalSchemaLocations A String containing
* namespace URI to schema location
* pairs, the same way it is accepted
* by the xsi:
* schemaLocation attribute.
* @param externalNoNamespaceSchemaLocation The schema location of the schema
* for elements without a namespace,
* the same way it is accepted by the
* xsi:noNamespaceSchemaLocation
* attribute.
* @return true, if the element validates against the
* schemas declared in it.
* @throws SAXException An error occurred parsing the document.
* @throws IOException An error occurred reading the document
* from its serialized representation.
* @throws ParserConfigurationException An error occurred configuring the XML
* @throws TransformerException An error occurred serializing the
* element.
*/
public static boolean validateElement(final Element element, final String externalSchemaLocations,
final String externalNoNamespaceSchemaLocation, final EntityResolver entityResolver)
throws ParserConfigurationException, IOException, SAXException, TransformerException {
byte[] docBytes;
SAXParser parser;
// create the SAX parser
if (symbolTable != null) {
parser = new SAXParser(symbolTable, grammarPool);
} else {
parser = new SAXParser();
}
// serialize the document
docBytes = serializeNode(element, "UTF-8");
// set up parser features and attributes
parser.setFeature(NAMESPACES_FEATURE, true);
parser.setFeature(VALIDATION_FEATURE, true);
parser.setFeature(SCHEMA_VALIDATION_FEATURE, true);
if (externalSchemaLocations != null) {
parser.setProperty(EXTERNAL_SCHEMA_LOCATION_PROPERTY, externalSchemaLocations);
}
if (externalNoNamespaceSchemaLocation != null) {
parser.setProperty(EXTERNAL_NO_NAMESPACE_SCHEMA_LOCATION_PROPERTY,
"externalNoNamespaceSchemaLocation");
}
// set up entity resolver and error handler
parser.setEntityResolver(entityResolver);
// parse validating
parser.parse(new InputSource(new ByteArrayInputStream(docBytes)));
return true;
}
/**
* Serialize the given DOM node.
*
* * The node will be serialized using the UTF-8 encoding. *
* * @param node The node to serialize. * @return String TheString representation of the given DOM node.
* @throws TransformerException An error occurred transforming the node to a
* String.
* @throws IOException An IO error occurred writing the node to a byte
* array.
*/
public static String serializeNode(final Node node) throws TransformerException, IOException {
return new String(serializeNode(node, "UTF-8", false), "UTF-8");
}
/**
* Serialize the given DOM node.
*
* * The node will be serialized using the UTF-8 encoding. *
* * @param node The node to serialize. * @param omitXmlDeclaration The boolean value for omitting the XML Declaration. * @return String TheString representation of the given DOM node.
* @throws TransformerException An error occurred transforming the node to a
* String.
* @throws IOException An IO error occurred writing the node to a byte
* array.
*/
public static String serializeNode(final Node node, final boolean omitXmlDeclaration)
throws TransformerException, IOException {
return new String(serializeNode(node, "UTF-8", omitXmlDeclaration), "UTF-8");
}
/**
* Serialize the given DOM node.
*
* * The node will be serialized using the UTF-8 encoding. *
* * @param node The node to serialize. * @param omitXmlDeclaration The boolean value for omitting the XML Declaration. * @param lineSeperator Sets the line seperator String of the parser * @return String TheString representation of the given DOM node.
* @throws TransformerException An error occurred transforming the node to a
* String.
* @throws IOException An IO error occurred writing the node to a byte
* array.
*/
public static String serializeNode(final Node node, final boolean omitXmlDeclaration,
final String lineSeperator) throws TransformerException, IOException {
return new String(serializeNode(node, "UTF-8", omitXmlDeclaration, lineSeperator), "UTF-8");
}
/**
* Serialize the given DOM node to a byte array.
*
* @param node The node to serialize.
* @param xmlEncoding The XML encoding to use.
* @return The serialized node, as a byte array. Using a compatible encoding
* this can easily be converted into a String.
* @throws TransformerException An error occurred transforming the node to a
* byte array.
* @throws IOException An IO error occurred writing the node to a byte
* array.
*/
public static byte[] serializeNode(final Node node, final String xmlEncoding)
throws TransformerException, IOException {
return serializeNode(node, xmlEncoding, false);
}
/**
* Serialize the given DOM node to a byte array.
*
* @param node The node to serialize.
* @param xmlEncoding The XML encoding to use.
* @param omitDeclaration The boolean value for omitting the XML Declaration.
* @return The serialized node, as a byte array. Using a compatible encoding
* this can easily be converted into a String.
* @throws TransformerException An error occurred transforming the node to a
* byte array.
* @throws IOException An IO error occurred writing the node to a byte
* array.
*/
public static byte[] serializeNode(final Node node, final String xmlEncoding,
final boolean omitDeclaration) throws TransformerException, IOException {
return serializeNode(node, xmlEncoding, omitDeclaration, null);
}
/**
* Serialize the given DOM node to a byte array.
*
* @param node The node to serialize.
* @param xmlEncoding The XML encoding to use.
* @param omitDeclaration The boolean value for omitting the XML Declaration.
* @param lineSeperator Sets the line seperator String of the parser
* @return The serialized node, as a byte array. Using a compatible encoding
* this can easily be converted into a String.
* @throws TransformerException An error occurred transforming the node to a
* byte array.
* @throws IOException An IO error occurred writing the node to a byte
* array.
*/
public static byte[] serializeNode(final Node node, final String xmlEncoding,
final boolean omitDeclaration, final String lineSeperator)
throws TransformerException, IOException {
final TransformerFactory transformerFactory = TransformerFactory.newInstance();
final Transformer transformer = transformerFactory.newTransformer();
final ByteArrayOutputStream bos = new ByteArrayOutputStream(16384);
transformer.setOutputProperty(OutputKeys.METHOD, "xml");
transformer.setOutputProperty(OutputKeys.ENCODING, xmlEncoding);
final String omit = omitDeclaration ? "yes" : "no";
transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, omit);
if (null != lineSeperator) {
transformer.setOutputProperty("{http://xml.apache.org/xalan}line-separator", lineSeperator);
// does not work for xalan <= 2.5.1
}
transformer.transform(new DOMSource(node), new StreamResult(bos));
bos.flush();
bos.close();
return bos.toByteArray();
}
/**
* Return the text that a node contains.
*
* * This routine: *
*String
* value to String value mapping).
*/
public static Map getNamespaceDeclarations(Node node) {
final Map nsDecls = new HashMap();
int i;
do {
if (node.hasAttributes()) {
final NamedNodeMap attrs = node.getAttributes();
for (i = 0; i < attrs.getLength(); i++) {
final Attr attr = (Attr) attrs.item(i);
// add prefix mapping if none exists
if ("xmlns".equals(attr.getPrefix()) || "xmlns".equals(attr.getName())) {
final String nsPrefix = attr.getPrefix() != null ? attr.getLocalName() : "";
if (nsDecls.get(nsPrefix) == null) {
nsDecls.put(nsPrefix, attr.getValue());
}
}
}
}
} while ((node = node.getParentNode()) != null);
return nsDecls;
}
/**
* Add all namespace declarations declared in the parent(s) of a given element
* and used in the subtree of the given element to the given element.
*
* @param context The element to which to add the namespaces.
*/
public static void localizeNamespaceDeclarations(final Element context) {
final Node parent = context.getParentNode();
if (parent != null) {
final Map namespaces = getNamespaceDeclarations(context.getParentNode());
final Set nsUris = collectNamespaceUris(context);
Iterator iter;
for (iter = namespaces.entrySet().iterator(); iter.hasNext();) {
final Map.Entry e = (Map.Entry) iter.next();
if (nsUris.contains(e.getValue())) {
final String prefix = (String) e.getKey();
final String nsUri = (String) e.getValue();
final String nsAttrName = "".equals(prefix) ? "xmlns" : "xmlns:" + prefix;
context.setAttributeNS(XmlNamespaceConstants.XMLNS_NS_URI, nsAttrName, nsUri);
}
}
}
}
/**
* Collect all the namespace URIs used in the subtree of a given element.
*
* @param context The element that should be searched for namespace URIs.
* @return All namespace URIs used in the subtree of context,
* including the ones used in context itself.
*/
public static Set collectNamespaceUris(final Element context) {
final Set result = new HashSet();
collectNamespaceUrisImpl(context, result);
return result;
}
/**
* A recursive method to do the work of collectNamespaceURIs.
*
* @param context The context element to evaluate.
* @param result The result, passed as a parameter to avoid unnecessary
* instantiations of Set.
*/
private static void collectNamespaceUrisImpl(final Element context, final Set result) {
final NamedNodeMap attrs = context.getAttributes();
final NodeList childNodes = context.getChildNodes();
String nsUri;
int i;
// add the namespace of the context element
nsUri = context.getNamespaceURI();
if (nsUri != null && nsUri != XmlNamespaceConstants.XMLNS_NS_URI) {
result.add(nsUri);
}
// add all namespace URIs from attributes
for (i = 0; i < attrs.getLength(); i++) {
nsUri = attrs.item(i).getNamespaceURI();
if (nsUri != null && nsUri != XmlNamespaceConstants.XMLNS_NS_URI) {
result.add(nsUri);
}
}
// add all namespaces from subelements
for (i = 0; i < childNodes.getLength(); i++) {
final Node node = childNodes.item(i);
if (node.getNodeType() == Node.ELEMENT_NODE) {
collectNamespaceUrisImpl((Element) node, result);
}
}
}
/**
* Check, that each attribute node in the given NodeList has its
* parent in the NodeList as well.
*
* @param nodes The NodeList to check.
* @return true, if each attribute node in nodes has
* its parent in nodes as well.
*/
public static boolean checkAttributeParentsInNodeList(final NodeList nodes) {
final Set nodeSet = new HashSet();
int i;
// put the nodes into the nodeSet
for (i = 0; i < nodes.getLength(); i++) {
nodeSet.add(nodes.item(i));
}
// check that each attribute node's parent is in the node list
for (i = 0; i < nodes.getLength(); i++) {
final Node n = nodes.item(i);
if (n.getNodeType() == Node.ATTRIBUTE_NODE) {
final Attr attr = (Attr) n;
final Element owner = attr.getOwnerElement();
if (owner == null && !isNamespaceDeclaration(attr)) {
return false;
}
if (!nodeSet.contains(owner) && !isNamespaceDeclaration(attr)) {
return false;
}
}
}
return true;
}
/**
* Convert an unstructured NodeList into a
* DocumentFragment.
*
* @param nodeList Contains the node list to be converted into a DOM
* DocumentFragment.
* @return the resulting DocumentFragment. The DocumentFragment will be backed
* by a new DOM Document, i.e. all noded of the node list will be
* cloned.
* @throws ParserConfigurationException An error occurred creating the
* DocumentFragment.
* @precondition The nodes in the node list appear in document order
* @precondition for each Attr node in the node list, the owning Element is in
* the node list as well.
* @precondition each Element or Attr node in the node list is namespace aware.
*/
public static DocumentFragment nodeList2DocumentFragment(final NodeList nodeList)
throws ParserConfigurationException {
final DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
final Document doc = builder.newDocument();
final DocumentFragment result = doc.createDocumentFragment();
if (null == nodeList || nodeList.getLength() == 0) {
return result;
}
int currPos = 0;
currPos = nodeList2DocumentFragment(nodeList, currPos, result, null, null) + 1;
while (currPos < nodeList.getLength()) {
currPos = nodeList2DocumentFragment(nodeList, currPos, result, null, null) + 1;
}
return result;
}
/**
* Helper method for the nodeList2DocumentFragment.
*
* @param nodeList The NodeList to convert.
* @param currPos The current position in the nodeList.
* @param result The resulting DocumentFragment.
* @param currOrgElem The current original element.
* @param currClonedElem The current cloned element.
* @return The current position.
*/
private static int nodeList2DocumentFragment(final NodeList nodeList, int currPos,
final DocumentFragment result, Element currOrgElem, Element currClonedElem) {
while (currPos < nodeList.getLength()) {
final Node currentNode = nodeList.item(currPos);
switch (currentNode.getNodeType()) {
case Node.COMMENT_NODE:
case Node.PROCESSING_INSTRUCTION_NODE:
case Node.TEXT_NODE: {
// Append current node either to resulting DocumentFragment or to
// current cloned Element
if (null == currClonedElem) {
result.appendChild(result.getOwnerDocument().importNode(currentNode, false));
} else {
// Stop processing if current Node is not a descendant of
// current Element
if (!isAncestor(currOrgElem, currentNode)) {
return --currPos;
}
currClonedElem.appendChild(result.getOwnerDocument().importNode(currentNode, false));
}
break;
}
case Node.ELEMENT_NODE: {
final Element nextCurrOrgElem = (Element) currentNode;
final Element nextCurrClonedElem = result.getOwnerDocument()
.createElementNS(nextCurrOrgElem.getNamespaceURI(), nextCurrOrgElem.getNodeName());
// Append current Node either to resulting DocumentFragment or to
// current cloned Element
if (null == currClonedElem) {
result.appendChild(nextCurrClonedElem);
currOrgElem = nextCurrOrgElem;
currClonedElem = nextCurrClonedElem;
} else {
// Stop processing if current Node is not a descendant of
// current Element
if (!isAncestor(currOrgElem, currentNode)) {
return --currPos;
}
currClonedElem.appendChild(nextCurrClonedElem);
}
// Process current Node (of type Element) recursively
currPos = nodeList2DocumentFragment(nodeList, ++currPos, result, nextCurrOrgElem,
nextCurrClonedElem);
break;
}
case Node.ATTRIBUTE_NODE: {
final Attr currAttr = (Attr) currentNode;
// GK 20030411: Hack to overcome problems with IAIK IXSIL
if (currAttr.getOwnerElement() == null) {
break;
}
if (currClonedElem == null) {
break;
}
// currClonedElem must be the owner Element of currAttr if
// preconditions are met
currClonedElem.setAttributeNS(currAttr.getNamespaceURI(), currAttr.getNodeName(),
currAttr.getValue());
break;
}
default: {
log.trace("Node type: {} not supported", currentNode.getNodeType());
// All other nodes will be ignored
}
}
currPos++;
}
return currPos;
}
/**
* Check, if the given attribute is a namespace declaration.
*
* @param attr The attribute to check.
* @return true, if the attribute is a namespace declaration,
* false otherwise.
*/
private static boolean isNamespaceDeclaration(final Attr attr) {
return XmlNamespaceConstants.XMLNS_NS_URI.equals(attr.getNamespaceURI());
}
/**
* Check, if a given DOM element is an ancestor of a given node.
*
* @param candAnc The DOM element to check for being the ancestor.
* @param cand The node to check for being the child.
* @return true, if candAnc is an (indirect) ancestor
* of cand; false otherwise.
*/
public static boolean isAncestor(final Element candAnc, final Node cand) {
Node currPar = cand.getParentNode();
while (currPar != null) {
if (candAnc == currPar) {
return true;
}
currPar = currPar.getParentNode();
}
return false;
}
/**
* Selects the (first) element from a node list and returns it.
*
* @param nl The NodeList to get the element from.
* @return The (first) element included in the node list or null if
* the node list is null or empty or no element is included
* in the list.
*/
public static Element getElementFromNodeList(final NodeList nl) {
if (nl == null || nl.getLength() == 0) {
return null;
}
for (int i = 0; i < nl.getLength(); i++) {
final Node node = nl.item(i);
if (node.getNodeType() == Node.ELEMENT_NODE) {
return (Element) node;
}
}
return null;
}
/**
* Returns all child elements of the given element.
*
* @param parent The element to get the child elements from.
*
* @return A list including all child elements of the given element. Maybe empty
* if the parent element has no child elements.
*/
public static List getChildElements(final Element parent) {
final Vector v = new Vector();
final NodeList nl = parent.getChildNodes();
final int length = nl.getLength();
for (int i = 0; i < length; i++) {
final Node node = nl.item(i);
if (node.getNodeType() == Node.ELEMENT_NODE) {
v.add(node);
}
}
return v;
}
/**
* Returns a byte array from given node.
*
* @param node Element node
* @return transformed node
* @throws TransformerException in case of an error
*/
public static byte[] nodeToByteArray(final Node node) throws TransformerException {
final Source source = new DOMSource(node);
final ByteArrayOutputStream out = new ByteArrayOutputStream();
// StringWriter stringWriter = new StringWriter();
final Result result = new StreamResult(out);
final TransformerFactory factory = TransformerFactory.newInstance();
final Transformer transformer = factory.newTransformer();
transformer.transform(source, result);
return out.toByteArray();
}
}