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package com.itextpdf.xmp.impl;

import java.util.List;
import java.util.ArrayList;
import java.util.Iterator;

import org.w3c.dom.Attr;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;

import com.itextpdf.xmp.XMPConst;
import com.itextpdf.xmp.XMPError;
import com.itextpdf.xmp.XMPException;
import com.itextpdf.xmp.XMPMetaFactory;
import com.itextpdf.xmp.XMPSchemaRegistry;
import com.itextpdf.xmp.options.PropertyOptions;


/**
 * Parser for "normal" XML serialisation of RDF.  
 * 
 * @since   14.07.2006
 */
public class ParseRDF implements XMPError, XMPConst
{
	/** */
	public static final int RDFTERM_OTHER = 0;
	/** Start of coreSyntaxTerms. */
	public static final int RDFTERM_RDF = 1;
	/** */
	public static final int RDFTERM_ID = 2;
	/** */
	public static final int RDFTERM_ABOUT = 3;
	/** */
	public static final int RDFTERM_PARSE_TYPE = 4;
	/** */
	public static final int RDFTERM_RESOURCE = 5;
	/** */
	public static final int RDFTERM_NODE_ID = 6;
	/** End of coreSyntaxTerms */
	public static final int RDFTERM_DATATYPE = 7;
	/** Start of additions for syntax Terms. */
	public static final int RDFTERM_DESCRIPTION = 8; 
	/** End of of additions for syntaxTerms. */
	public static final int RDFTERM_LI = 9;
	/** Start of oldTerms. */
	public static final int RDFTERM_ABOUT_EACH = 10; 
	/** */
	public static final int RDFTERM_ABOUT_EACH_PREFIX = 11;
	/** End of oldTerms. */
	public static final int RDFTERM_BAG_ID = 12;
	/** */
	public static final int RDFTERM_FIRST_CORE = RDFTERM_RDF;
	/** */
	public static final int RDFTERM_LAST_CORE = RDFTERM_DATATYPE;
	/** ! Yes, the syntax terms include the core terms. */
	public static final int RDFTERM_FIRST_SYNTAX = RDFTERM_FIRST_CORE;
	/** */
	public static final int RDFTERM_LAST_SYNTAX = RDFTERM_LI;
	/** */
	public static final int RDFTERM_FIRST_OLD = RDFTERM_ABOUT_EACH;
	/** */
	public static final int RDFTERM_LAST_OLD = RDFTERM_BAG_ID;

	/** this prefix is used for default namespaces */
	public static final String DEFAULT_PREFIX = "_dflt";
	
	
	
	/**
	 * The main parsing method. The XML tree is walked through from the root node and and XMP tree
	 * is created. This is a raw parse, the normalisation of the XMP tree happens outside.
	 * 
	 * @param xmlRoot the XML root node
	 * @return Returns an XMP metadata object (not normalized)
	 * @throws XMPException Occurs if the parsing fails for any reason.
	 */
	static XMPMetaImpl parse(Node xmlRoot) throws XMPException
	{
		XMPMetaImpl xmp = new XMPMetaImpl();
		rdf_RDF(xmp, xmlRoot);
		return xmp;
	}
	
	
	/**
	 * Each of these parsing methods is responsible for recognizing an RDF
	 * syntax production and adding the appropriate structure to the XMP tree.
	 * They simply return for success, failures will throw an exception.
	 * 
	 * @param xmp the xmp metadata object that is generated
	 * @param rdfRdfNode the top-level xml node
	 * @throws XMPException thown on parsing errors
	 */
	static void rdf_RDF(XMPMetaImpl xmp, Node rdfRdfNode) throws XMPException
	{
		if (rdfRdfNode.hasAttributes())
		{
			rdf_NodeElementList (xmp, xmp.getRoot(), rdfRdfNode);
		}	
		else
		{	
			throw new XMPException("Invalid attributes of rdf:RDF element", BADRDF);
		}
	}
	
	
	/**
	 * 7.2.10 nodeElementList
* ws* ( nodeElement ws* )* * * Note: this method is only called from the rdf:RDF-node (top level) * @param xmp the xmp metadata object that is generated * @param xmpParent the parent xmp node * @param rdfRdfNode the top-level xml node * @throws XMPException thown on parsing errors */ private static void rdf_NodeElementList(XMPMetaImpl xmp, XMPNode xmpParent, Node rdfRdfNode) throws XMPException { for (int i = 0; i < rdfRdfNode.getChildNodes().getLength(); i++) { Node child = rdfRdfNode.getChildNodes().item(i); // filter whitespaces (and all text nodes) if (!isWhitespaceNode(child)) { rdf_NodeElement (xmp, xmpParent, child, true); } } } /** * 7.2.5 nodeElementURIs * anyURI - ( coreSyntaxTerms | rdf:li | oldTerms ) * * 7.2.11 nodeElement * start-element ( URI == nodeElementURIs, * attributes == set ( ( idAttr | nodeIdAttr | aboutAttr )?, propertyAttr* ) ) * propertyEltList * end-element() * * A node element URI is rdf:Description or anything else that is not an RDF * term. * * @param xmp the xmp metadata object that is generated * @param xmpParent the parent xmp node * @param xmlNode the currently processed XML node * @param isTopLevel Flag if the node is a top-level node * @throws XMPException thown on parsing errors */ private static void rdf_NodeElement(XMPMetaImpl xmp, XMPNode xmpParent, Node xmlNode, boolean isTopLevel) throws XMPException { int nodeTerm = getRDFTermKind (xmlNode); if (nodeTerm != RDFTERM_DESCRIPTION && nodeTerm != RDFTERM_OTHER) { throw new XMPException("Node element must be rdf:Description or typed node", BADRDF); } else if (isTopLevel && nodeTerm == RDFTERM_OTHER) { throw new XMPException("Top level typed node not allowed", BADXMP); } else { rdf_NodeElementAttrs (xmp, xmpParent, xmlNode, isTopLevel); rdf_PropertyElementList (xmp, xmpParent, xmlNode, isTopLevel); } } /** * * 7.2.7 propertyAttributeURIs * anyURI - ( coreSyntaxTerms | rdf:Description | rdf:li | oldTerms ) * * 7.2.11 nodeElement * start-element ( URI == nodeElementURIs, * attributes == set ( ( idAttr | nodeIdAttr | aboutAttr )?, propertyAttr* ) ) * propertyEltList * end-element() * * Process the attribute list for an RDF node element. A property attribute URI is * anything other than an RDF term. The rdf:ID and rdf:nodeID attributes are simply ignored, * as are rdf:about attributes on inner nodes. * * @param xmp the xmp metadata object that is generated * @param xmpParent the parent xmp node * @param xmlNode the currently processed XML node * @param isTopLevel Flag if the node is a top-level node * @throws XMPException thown on parsing errors */ private static void rdf_NodeElementAttrs(XMPMetaImpl xmp, XMPNode xmpParent, Node xmlNode, boolean isTopLevel) throws XMPException { // Used to detect attributes that are mutually exclusive. int exclusiveAttrs = 0; for (int i = 0; i < xmlNode.getAttributes().getLength(); i++) { Node attribute = xmlNode.getAttributes().item(i); // quick hack, ns declarations do not appear in C++ // ignore "ID" without namespace if ("xmlns".equals(attribute.getPrefix()) || (attribute.getPrefix() == null && "xmlns".equals(attribute.getNodeName()))) { continue; } int attrTerm = getRDFTermKind(attribute); switch (attrTerm) { case RDFTERM_ID: case RDFTERM_NODE_ID: case RDFTERM_ABOUT: if (exclusiveAttrs > 0) { throw new XMPException("Mutally exclusive about, ID, nodeID attributes", BADRDF); } exclusiveAttrs++; if (isTopLevel && (attrTerm == RDFTERM_ABOUT)) { // This is the rdf:about attribute on a top level node. Set // the XMP tree name if // it doesn't have a name yet. Make sure this name matches // the XMP tree name. if (xmpParent.getName() != null && xmpParent.getName().length() > 0) { if (!xmpParent.getName().equals(attribute.getNodeValue())) { throw new XMPException("Mismatched top level rdf:about values", BADXMP); } } else { xmpParent.setName(attribute.getNodeValue()); } } break; case RDFTERM_OTHER: addChildNode(xmp, xmpParent, attribute, attribute.getNodeValue(), isTopLevel); break; default: throw new XMPException("Invalid nodeElement attribute", BADRDF); } } } /** * 7.2.13 propertyEltList * ws* ( propertyElt ws* )* * * @param xmp the xmp metadata object that is generated * @param xmpParent the parent xmp node * @param xmlParent the currently processed XML node * @param isTopLevel Flag if the node is a top-level node * @throws XMPException thown on parsing errors */ private static void rdf_PropertyElementList(XMPMetaImpl xmp, XMPNode xmpParent, Node xmlParent, boolean isTopLevel) throws XMPException { for (int i = 0; i < xmlParent.getChildNodes().getLength(); i++) { Node currChild = xmlParent.getChildNodes().item(i); if (isWhitespaceNode(currChild)) { continue; } else if (currChild.getNodeType() != Node.ELEMENT_NODE) { throw new XMPException("Expected property element node not found", BADRDF); } else { rdf_PropertyElement(xmp, xmpParent, currChild, isTopLevel); } } } /** * 7.2.14 propertyElt * * resourcePropertyElt | literalPropertyElt | parseTypeLiteralPropertyElt | * parseTypeResourcePropertyElt | parseTypeCollectionPropertyElt | * parseTypeOtherPropertyElt | emptyPropertyElt * * 7.2.15 resourcePropertyElt * start-element ( URI == propertyElementURIs, attributes == set ( idAttr? ) ) * ws* nodeElement ws* * end-element() * * 7.2.16 literalPropertyElt * start-element ( * URI == propertyElementURIs, attributes == set ( idAttr?, datatypeAttr?) ) * text() * end-element() * * 7.2.17 parseTypeLiteralPropertyElt * start-element ( * URI == propertyElementURIs, attributes == set ( idAttr?, parseLiteral ) ) * literal * end-element() * * 7.2.18 parseTypeResourcePropertyElt * start-element ( * URI == propertyElementURIs, attributes == set ( idAttr?, parseResource ) ) * propertyEltList * end-element() * * 7.2.19 parseTypeCollectionPropertyElt * start-element ( * URI == propertyElementURIs, attributes == set ( idAttr?, parseCollection ) ) * nodeElementList * end-element() * * 7.2.20 parseTypeOtherPropertyElt * start-element ( URI == propertyElementURIs, attributes == set ( idAttr?, parseOther ) ) * propertyEltList * end-element() * * 7.2.21 emptyPropertyElt * start-element ( URI == propertyElementURIs, * attributes == set ( idAttr?, ( resourceAttr | nodeIdAttr )?, propertyAttr* ) ) * end-element() * * The various property element forms are not distinguished by the XML element name, * but by their attributes for the most part. The exceptions are resourcePropertyElt and * literalPropertyElt. They are distinguished by their XML element content. * * NOTE: The RDF syntax does not explicitly include the xml:lang attribute although it can * appear in many of these. We have to allow for it in the attibute counts below. * * @param xmp the xmp metadata object that is generated * @param xmpParent the parent xmp node * @param xmlNode the currently processed XML node * @param isTopLevel Flag if the node is a top-level node * @throws XMPException thown on parsing errors */ private static void rdf_PropertyElement(XMPMetaImpl xmp, XMPNode xmpParent, Node xmlNode, boolean isTopLevel) throws XMPException { int nodeTerm = getRDFTermKind (xmlNode); if (!isPropertyElementName(nodeTerm)) { throw new XMPException("Invalid property element name", BADRDF); } // remove the namespace-definitions from the list NamedNodeMap attributes = xmlNode.getAttributes(); List nsAttrs = null; for (int i = 0; i < attributes.getLength(); i++) { Node attribute = attributes.item(i); if ("xmlns".equals(attribute.getPrefix()) || (attribute.getPrefix() == null && "xmlns".equals(attribute.getNodeName()))) { if (nsAttrs == null) { nsAttrs = new ArrayList(); } nsAttrs.add(attribute.getNodeName()); } } if (nsAttrs != null) { for (Iterator it = nsAttrs.iterator(); it.hasNext();) { String ns = (String) it.next(); attributes.removeNamedItem(ns); } } if (attributes.getLength() > 3) { // Only an emptyPropertyElt can have more than 3 attributes. rdf_EmptyPropertyElement(xmp, xmpParent, xmlNode, isTopLevel); } else { // Look through the attributes for one that isn't rdf:ID or xml:lang, // it will usually tell what we should be dealing with. // The called routines must verify their specific syntax! for (int i = 0; i < attributes.getLength(); i++) { Node attribute = attributes.item(i); String attrLocal = attribute.getLocalName(); String attrNS = attribute.getNamespaceURI(); String attrValue = attribute.getNodeValue(); if (!(XML_LANG.equals(attribute.getNodeName()) && !("ID".equals(attrLocal) && NS_RDF.equals(attrNS)))) { if ("datatype".equals(attrLocal) && NS_RDF.equals(attrNS)) { rdf_LiteralPropertyElement (xmp, xmpParent, xmlNode, isTopLevel); } else if (!("parseType".equals(attrLocal) && NS_RDF.equals(attrNS))) { rdf_EmptyPropertyElement (xmp, xmpParent, xmlNode, isTopLevel); } else if ("Literal".equals(attrValue)) { rdf_ParseTypeLiteralPropertyElement(); } else if ("Resource".equals(attrValue)) { rdf_ParseTypeResourcePropertyElement(xmp, xmpParent, xmlNode, isTopLevel); } else if ("Collection".equals(attrValue)) { rdf_ParseTypeCollectionPropertyElement(); } else { rdf_ParseTypeOtherPropertyElement(); } return; } } // Only rdf:ID and xml:lang, could be a resourcePropertyElt, a literalPropertyElt, // or an emptyPropertyElt. Look at the child XML nodes to decide which. if (xmlNode.hasChildNodes()) { for (int i = 0; i < xmlNode.getChildNodes().getLength(); i++) { Node currChild = xmlNode.getChildNodes().item(i); if (currChild.getNodeType() != Node.TEXT_NODE) { rdf_ResourcePropertyElement (xmp, xmpParent, xmlNode, isTopLevel); return; } } rdf_LiteralPropertyElement (xmp, xmpParent, xmlNode, isTopLevel); } else { rdf_EmptyPropertyElement (xmp, xmpParent, xmlNode, isTopLevel); } } } /** * 7.2.15 resourcePropertyElt * start-element ( URI == propertyElementURIs, attributes == set ( idAttr? ) ) * ws* nodeElement ws* * end-element() * * This handles structs using an rdf:Description node, * arrays using rdf:Bag/Seq/Alt, and typedNodes. It also catches and cleans up qualified * properties written with rdf:Description and rdf:value. * * @param xmp the xmp metadata object that is generated * @param xmpParent the parent xmp node * @param xmlNode the currently processed XML node * @param isTopLevel Flag if the node is a top-level node * @throws XMPException thown on parsing errors */ private static void rdf_ResourcePropertyElement(XMPMetaImpl xmp, XMPNode xmpParent, Node xmlNode, boolean isTopLevel) throws XMPException { if (isTopLevel && "iX:changes".equals(xmlNode.getNodeName())) { // Strip old "punchcard" chaff which has on the prefix "iX:". return; } XMPNode newCompound = addChildNode(xmp, xmpParent, xmlNode, "", isTopLevel); // walk through the attributes for (int i = 0; i < xmlNode.getAttributes().getLength(); i++) { Node attribute = xmlNode.getAttributes().item(i); if ("xmlns".equals(attribute.getPrefix()) || (attribute.getPrefix() == null && "xmlns".equals(attribute.getNodeName()))) { continue; } String attrLocal = attribute.getLocalName(); String attrNS = attribute.getNamespaceURI(); if (XML_LANG.equals(attribute.getNodeName())) { addQualifierNode (newCompound, XML_LANG, attribute.getNodeValue()); } else if ("ID".equals(attrLocal) && NS_RDF.equals(attrNS)) { continue; // Ignore all rdf:ID attributes. } else { throw new XMPException( "Invalid attribute for resource property element", BADRDF); } } // walk through the children Node currChild = null; boolean found = false; int i; for (i = 0; i < xmlNode.getChildNodes().getLength(); i++) { currChild = xmlNode.getChildNodes().item(i); if (!isWhitespaceNode(currChild)) { if (currChild.getNodeType() == Node.ELEMENT_NODE && !found) { boolean isRDF = NS_RDF.equals(currChild.getNamespaceURI()); String childLocal = currChild.getLocalName(); if (isRDF && "Bag".equals(childLocal)) { newCompound.getOptions().setArray(true); } else if (isRDF && "Seq".equals(childLocal)) { newCompound.getOptions().setArray(true).setArrayOrdered(true); } else if (isRDF && "Alt".equals(childLocal)) { newCompound.getOptions().setArray(true).setArrayOrdered(true) .setArrayAlternate(true); } else { newCompound.getOptions().setStruct(true); if (!isRDF && !"Description".equals(childLocal)) { String typeName = currChild.getNamespaceURI(); if (typeName == null) { throw new XMPException( "All XML elements must be in a namespace", BADXMP); } typeName += ':' + childLocal; addQualifierNode (newCompound, "rdf:type", typeName); } } rdf_NodeElement (xmp, newCompound, currChild, false); if (newCompound.getHasValueChild()) { fixupQualifiedNode (newCompound); } else if (newCompound.getOptions().isArrayAlternate()) { XMPNodeUtils.detectAltText(newCompound); } found = true; } else if (found) { // found second child element throw new XMPException( "Invalid child of resource property element", BADRDF); } else { throw new XMPException( "Children of resource property element must be XML elements", BADRDF); } } } if (!found) { // didn't found any child elements throw new XMPException("Missing child of resource property element", BADRDF); } } /** * 7.2.16 literalPropertyElt * start-element ( URI == propertyElementURIs, * attributes == set ( idAttr?, datatypeAttr?) ) * text() * end-element() * * Add a leaf node with the text value and qualifiers for the attributes. * @param xmp the xmp metadata object that is generated * @param xmpParent the parent xmp node * @param xmlNode the currently processed XML node * @param isTopLevel Flag if the node is a top-level node * @throws XMPException thown on parsing errors */ private static void rdf_LiteralPropertyElement(XMPMetaImpl xmp, XMPNode xmpParent, Node xmlNode, boolean isTopLevel) throws XMPException { XMPNode newChild = addChildNode (xmp, xmpParent, xmlNode, null, isTopLevel); for (int i = 0; i < xmlNode.getAttributes().getLength(); i++) { Node attribute = xmlNode.getAttributes().item(i); if ("xmlns".equals(attribute.getPrefix()) || (attribute.getPrefix() == null && "xmlns".equals(attribute.getNodeName()))) { continue; } String attrNS = attribute.getNamespaceURI(); String attrLocal = attribute.getLocalName(); if (XML_LANG.equals(attribute.getNodeName())) { addQualifierNode(newChild, XML_LANG, attribute.getNodeValue()); } else if (NS_RDF.equals(attrNS) && ("ID".equals(attrLocal) || "datatype".equals(attrLocal))) { continue; // Ignore all rdf:ID and rdf:datatype attributes. } else { throw new XMPException( "Invalid attribute for literal property element", BADRDF); } } String textValue = ""; for (int i = 0; i < xmlNode.getChildNodes().getLength(); i++) { Node child = xmlNode.getChildNodes().item(i); if (child.getNodeType() == Node.TEXT_NODE) { textValue += child.getNodeValue(); } else { throw new XMPException("Invalid child of literal property element", BADRDF); } } newChild.setValue(textValue); } /** * 7.2.17 parseTypeLiteralPropertyElt * start-element ( URI == propertyElementURIs, * attributes == set ( idAttr?, parseLiteral ) ) * literal * end-element() * * @throws XMPException thown on parsing errors */ private static void rdf_ParseTypeLiteralPropertyElement() throws XMPException { throw new XMPException("ParseTypeLiteral property element not allowed", BADXMP); } /** * 7.2.18 parseTypeResourcePropertyElt * start-element ( URI == propertyElementURIs, * attributes == set ( idAttr?, parseResource ) ) * propertyEltList * end-element() * * Add a new struct node with a qualifier for the possible rdf:ID attribute. * Then process the XML child nodes to get the struct fields. * * @param xmp the xmp metadata object that is generated * @param xmpParent the parent xmp node * @param xmlNode the currently processed XML node * @param isTopLevel Flag if the node is a top-level node * @throws XMPException thown on parsing errors */ private static void rdf_ParseTypeResourcePropertyElement(XMPMetaImpl xmp, XMPNode xmpParent, Node xmlNode, boolean isTopLevel) throws XMPException { XMPNode newStruct = addChildNode (xmp, xmpParent, xmlNode, "", isTopLevel); newStruct.getOptions().setStruct(true); for (int i = 0; i < xmlNode.getAttributes().getLength(); i++) { Node attribute = xmlNode.getAttributes().item(i); if ("xmlns".equals(attribute.getPrefix()) || (attribute.getPrefix() == null && "xmlns".equals(attribute.getNodeName()))) { continue; } String attrLocal = attribute.getLocalName(); String attrNS = attribute.getNamespaceURI(); if (XML_LANG.equals(attribute.getNodeName())) { addQualifierNode (newStruct, XML_LANG, attribute.getNodeValue()); } else if (NS_RDF.equals(attrNS) && ("ID".equals(attrLocal) || "parseType".equals(attrLocal))) { continue; // The caller ensured the value is "Resource". // Ignore all rdf:ID attributes. } else { throw new XMPException("Invalid attribute for ParseTypeResource property element", BADRDF); } } rdf_PropertyElementList (xmp, newStruct, xmlNode, false); if (newStruct.getHasValueChild()) { fixupQualifiedNode (newStruct); } } /** * 7.2.19 parseTypeCollectionPropertyElt * start-element ( URI == propertyElementURIs, * attributes == set ( idAttr?, parseCollection ) ) * nodeElementList * end-element() * * @throws XMPException thown on parsing errors */ private static void rdf_ParseTypeCollectionPropertyElement() throws XMPException { throw new XMPException("ParseTypeCollection property element not allowed", BADXMP); } /** * 7.2.20 parseTypeOtherPropertyElt * start-element ( URI == propertyElementURIs, attributes == set ( idAttr?, parseOther ) ) * propertyEltList * end-element() * * @throws XMPException thown on parsing errors */ private static void rdf_ParseTypeOtherPropertyElement() throws XMPException { throw new XMPException("ParseTypeOther property element not allowed", BADXMP); } /** * 7.2.21 emptyPropertyElt * start-element ( URI == propertyElementURIs, * attributes == set ( * idAttr?, ( resourceAttr | nodeIdAttr )?, propertyAttr* ) ) * end-element() * * * * * * * An emptyPropertyElt is an element with no contained content, just a possibly empty set of * attributes. An emptyPropertyElt can represent three special cases of simple XMP properties: a * simple property with an empty value (ns:Prop1), a simple property whose value is a URI * (ns:Prop2), or a simple property with simple qualifiers (ns:Prop3). * An emptyPropertyElt can also represent an XMP struct whose fields are all simple and * unqualified (ns:Prop4). * * It is an error to use both rdf:value and rdf:resource - that can lead to invalid RDF in the * verbose form written using a literalPropertyElt. * * The XMP mapping for an emptyPropertyElt is a bit different from generic RDF, partly for * design reasons and partly for historical reasons. The XMP mapping rules are: *
    *
  1. If there is an rdf:value attribute then this is a simple property * with a text value. * All other attributes are qualifiers. *
  2. If there is an rdf:resource attribute then this is a simple property * with a URI value. * All other attributes are qualifiers. *
  3. If there are no attributes other than xml:lang, rdf:ID, or rdf:nodeID * then this is a simple * property with an empty value. *
  4. Otherwise this is a struct, the attributes other than xml:lang, rdf:ID, * or rdf:nodeID are fields. *
* * @param xmp the xmp metadata object that is generated * @param xmpParent the parent xmp node * @param xmlNode the currently processed XML node * @param isTopLevel Flag if the node is a top-level node * @throws XMPException thown on parsing errors */ private static void rdf_EmptyPropertyElement(XMPMetaImpl xmp, XMPNode xmpParent, Node xmlNode, boolean isTopLevel) throws XMPException { boolean hasPropertyAttrs = false; boolean hasResourceAttr = false; boolean hasNodeIDAttr = false; boolean hasValueAttr = false; Node valueNode = null; // ! Can come from rdf:value or rdf:resource. if (xmlNode.hasChildNodes()) { throw new XMPException( "Nested content not allowed with rdf:resource or property attributes", BADRDF); } // First figure out what XMP this maps to and remember the XML node for a simple value. for (int i = 0; i < xmlNode.getAttributes().getLength(); i++) { Node attribute = xmlNode.getAttributes().item(i); if ("xmlns".equals(attribute.getPrefix()) || (attribute.getPrefix() == null && "xmlns".equals(attribute.getNodeName()))) { continue; } int attrTerm = getRDFTermKind (attribute); switch (attrTerm) { case RDFTERM_ID : // Nothing to do. break; case RDFTERM_RESOURCE : if (hasNodeIDAttr) { throw new XMPException( "Empty property element can't have both rdf:resource and rdf:nodeID", BADRDF); } else if (hasValueAttr) { throw new XMPException( "Empty property element can't have both rdf:value and rdf:resource", BADXMP); } hasResourceAttr = true; if (!hasValueAttr) { valueNode = attribute; } break; case RDFTERM_NODE_ID: if (hasResourceAttr) { throw new XMPException( "Empty property element can't have both rdf:resource and rdf:nodeID", BADRDF); } hasNodeIDAttr = true; break; case RDFTERM_OTHER: if ("value".equals(attribute.getLocalName()) && NS_RDF.equals(attribute.getNamespaceURI())) { if (hasResourceAttr) { throw new XMPException( "Empty property element can't have both rdf:value and rdf:resource", BADXMP); } hasValueAttr = true; valueNode = attribute; } else if (!XML_LANG.equals(attribute.getNodeName())) { hasPropertyAttrs = true; } break; default: throw new XMPException("Unrecognized attribute of empty property element", BADRDF); } } // Create the right kind of child node and visit the attributes again // to add the fields or qualifiers. // ! Because of implementation vagaries, // the xmpParent is the tree root for top level properties. // ! The schema is found, created if necessary, by addChildNode. XMPNode childNode = addChildNode(xmp, xmpParent, xmlNode, "", isTopLevel); boolean childIsStruct = false; if (hasValueAttr || hasResourceAttr) { childNode.setValue(valueNode != null ? valueNode.getNodeValue() : ""); if (!hasValueAttr) { // ! Might have both rdf:value and rdf:resource. childNode.getOptions().setURI(true); } } else if (hasPropertyAttrs) { childNode.getOptions().setStruct(true); childIsStruct = true; } for (int i = 0; i < xmlNode.getAttributes().getLength(); i++) { Node attribute = xmlNode.getAttributes().item(i); if (attribute == valueNode || "xmlns".equals(attribute.getPrefix()) || (attribute.getPrefix() == null && "xmlns".equals(attribute.getNodeName()))) { continue; // Skip the rdf:value or rdf:resource attribute holding the value. } int attrTerm = getRDFTermKind (attribute); switch (attrTerm) { case RDFTERM_ID : case RDFTERM_NODE_ID : break; // Ignore all rdf:ID and rdf:nodeID attributes. case RDFTERM_RESOURCE : addQualifierNode(childNode, "rdf:resource", attribute.getNodeValue()); break; case RDFTERM_OTHER : if (!childIsStruct) { addQualifierNode( childNode, attribute.getNodeName(), attribute.getNodeValue()); } else if (XML_LANG.equals(attribute.getNodeName())) { addQualifierNode (childNode, XML_LANG, attribute.getNodeValue()); } else { addChildNode (xmp, childNode, attribute, attribute.getNodeValue(), false); } break; default : throw new XMPException("Unrecognized attribute of empty property element", BADRDF); } } } /** * Adds a child node. * * @param xmp the xmp metadata object that is generated * @param xmpParent the parent xmp node * @param xmlNode the currently processed XML node * @param value Node value * @param isTopLevel Flag if the node is a top-level node * @return Returns the newly created child node. * @throws XMPException thown on parsing errors */ private static XMPNode addChildNode(XMPMetaImpl xmp, XMPNode xmpParent, Node xmlNode, String value, boolean isTopLevel) throws XMPException { XMPSchemaRegistry registry = XMPMetaFactory.getSchemaRegistry(); String namespace = xmlNode.getNamespaceURI(); String childName; if (namespace != null) { if (NS_DC_DEPRECATED.equals(namespace)) { // Fix a legacy DC namespace namespace = NS_DC; } String prefix = registry.getNamespacePrefix(namespace); if (prefix == null) { prefix = xmlNode.getPrefix() != null ? xmlNode.getPrefix() : DEFAULT_PREFIX; prefix = registry.registerNamespace(namespace, prefix); } childName = prefix + xmlNode.getLocalName(); } else { throw new XMPException( "XML namespace required for all elements and attributes", BADRDF); } // create schema node if not already there PropertyOptions childOptions = new PropertyOptions(); boolean isAlias = false; if (isTopLevel) { // Lookup the schema node, adjust the XMP parent pointer. // Incoming parent must be the tree root. XMPNode schemaNode = XMPNodeUtils.findSchemaNode(xmp.getRoot(), namespace, DEFAULT_PREFIX, true); schemaNode.setImplicit(false); // Clear the implicit node bit. // need runtime check for proper 32 bit code. xmpParent = schemaNode; // If this is an alias set the alias flag in the node // and the hasAliases flag in the tree. if (registry.findAlias(childName) != null) { isAlias = true; xmp.getRoot().setHasAliases(true); schemaNode.setHasAliases(true); } } // Make sure that this is not a duplicate of a named node. boolean isArrayItem = "rdf:li".equals(childName); boolean isValueNode = "rdf:value".equals(childName); // Create XMP node and so some checks XMPNode newChild = new XMPNode( childName, value, childOptions); newChild.setAlias(isAlias); // Add the new child to the XMP parent node, a value node first. if (!isValueNode) { xmpParent.addChild(newChild); } else { xmpParent.addChild(1, newChild); } if (isValueNode) { if (isTopLevel || !xmpParent.getOptions().isStruct()) { throw new XMPException("Misplaced rdf:value element", BADRDF); } xmpParent.setHasValueChild(true); } if (isArrayItem) { if (!xmpParent.getOptions().isArray()) { throw new XMPException("Misplaced rdf:li element", BADRDF); } newChild.setName(ARRAY_ITEM_NAME); } return newChild; } /** * Adds a qualifier node. * * @param xmpParent the parent xmp node * @param name the name of the qualifier which has to be * QName including the default prefix * @param value the value of the qualifier * @return Returns the newly created child node. * @throws XMPException thown on parsing errors */ private static XMPNode addQualifierNode(XMPNode xmpParent, String name, String value) throws XMPException { boolean isLang = XML_LANG.equals(name); XMPNode newQual = null; // normalize value of language qualifiers newQual = new XMPNode(name, isLang ? Utils.normalizeLangValue(value) : value, null); xmpParent.addQualifier(newQual); return newQual; } /** * The parent is an RDF pseudo-struct containing an rdf:value field. Fix the * XMP data model. The rdf:value node must be the first child, the other * children are qualifiers. The form, value, and children of the rdf:value * node are the real ones. The rdf:value node's qualifiers must be added to * the others. * * @param xmpParent the parent xmp node * @throws XMPException thown on parsing errors */ private static void fixupQualifiedNode(XMPNode xmpParent) throws XMPException { assert xmpParent.getOptions().isStruct() && xmpParent.hasChildren(); XMPNode valueNode = xmpParent.getChild(1); assert "rdf:value".equals(valueNode.getName()); // Move the qualifiers on the value node to the parent. // Make sure an xml:lang qualifier stays at the front. // Check for duplicate names between the value node's qualifiers and the parent's children. // The parent's children are about to become qualifiers. Check here, between the groups. // Intra-group duplicates are caught by XMPNode#addChild(...). if (valueNode.getOptions().getHasLanguage()) { if (xmpParent.getOptions().getHasLanguage()) { throw new XMPException("Redundant xml:lang for rdf:value element", BADXMP); } XMPNode langQual = valueNode.getQualifier(1); valueNode.removeQualifier(langQual); xmpParent.addQualifier(langQual); } // Start the remaining copy after the xml:lang qualifier. for (int i = 1; i <= valueNode.getQualifierLength(); i++) { XMPNode qualifier = valueNode.getQualifier(i); xmpParent.addQualifier(qualifier); } // Change the parent's other children into qualifiers. // This loop starts at 1, child 0 is the rdf:value node. for (int i = 2; i <= xmpParent.getChildrenLength(); i++) { XMPNode qualifier = xmpParent.getChild(i); xmpParent.addQualifier(qualifier); } // Move the options and value last, other checks need the parent's original options. // Move the value node's children to be the parent's children. assert xmpParent.getOptions().isStruct() || xmpParent.getHasValueChild(); xmpParent.setHasValueChild(false); xmpParent.getOptions().setStruct(false); xmpParent.getOptions().mergeWith(valueNode.getOptions()); xmpParent.setValue(valueNode.getValue()); xmpParent.removeChildren(); for (Iterator it = valueNode.iterateChildren(); it.hasNext();) { XMPNode child = (XMPNode) it.next(); xmpParent.addChild(child); } } /** * Checks if the node is a white space. * @param node an XML-node * @return Returns whether the node is a whitespace node, * i.e. a text node that contains only whitespaces. */ private static boolean isWhitespaceNode(Node node) { if (node.getNodeType() != Node.TEXT_NODE) { return false; } String value = node.getNodeValue(); for (int i = 0; i < value.length(); i++) { if (!Character.isWhitespace(value.charAt(i))) { return false; } } return true; } /** * 7.2.6 propertyElementURIs * anyURI - ( coreSyntaxTerms | rdf:Description | oldTerms ) * * @param term the term id * @return Return true if the term is a property element name. */ private static boolean isPropertyElementName(int term) { if (term == RDFTERM_DESCRIPTION || isOldTerm(term)) { return false; } else { return (!isCoreSyntaxTerm(term)); } } /** * 7.2.4 oldTerms
* rdf:aboutEach | rdf:aboutEachPrefix | rdf:bagID * * @param term the term id * @return Returns true if the term is an old term. */ private static boolean isOldTerm(int term) { return RDFTERM_FIRST_OLD <= term && term <= RDFTERM_LAST_OLD; } /** * 7.2.2 coreSyntaxTerms
* rdf:RDF | rdf:ID | rdf:about | rdf:parseType | rdf:resource | rdf:nodeID | * rdf:datatype * * @param term the term id * @return Return true if the term is a core syntax term */ private static boolean isCoreSyntaxTerm(int term) { return RDFTERM_FIRST_CORE <= term && term <= RDFTERM_LAST_CORE; } /** * Determines the ID for a certain RDF Term. * Arranged to hopefully minimize the parse time for large XMP. * * @param node an XML node * @return Returns the term ID. */ private static int getRDFTermKind(Node node) { String localName = node.getLocalName(); String namespace = node.getNamespaceURI(); if ( namespace == null && ("about".equals(localName) || "ID".equals(localName)) && (node instanceof Attr) && NS_RDF.equals(((Attr) node).getOwnerElement().getNamespaceURI()) ) { namespace = NS_RDF; } if (NS_RDF.equals(namespace)) { if ("li".equals(localName)) { return RDFTERM_LI; } else if ("parseType".equals(localName)) { return RDFTERM_PARSE_TYPE; } else if ("Description".equals(localName)) { return RDFTERM_DESCRIPTION; } else if ("about".equals(localName)) { return RDFTERM_ABOUT; } else if ("resource".equals(localName)) { return RDFTERM_RESOURCE; } else if ("RDF".equals(localName)) { return RDFTERM_RDF; } else if ("ID".equals(localName)) { return RDFTERM_ID; } else if ("nodeID".equals(localName)) { return RDFTERM_NODE_ID; } else if ("datatype".equals(localName)) { return RDFTERM_DATATYPE; } else if ("aboutEach".equals(localName)) { return RDFTERM_ABOUT_EACH; } else if ("aboutEachPrefix".equals(localName)) { return RDFTERM_ABOUT_EACH_PREFIX; } else if ("bagID".equals(localName)) { return RDFTERM_BAG_ID; } } return RDFTERM_OTHER; } }




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