parserdf.java

flash xmp sdk,flash官方SDK

// =================================================================================================
// ADOBE SYSTEMS INCORPORATED
// Copyright 2006 Adobe Systems Incorporated
// All Rights Reserved
//
// NOTICE:  Adobe permits you to use, modify, and distribute this file in accordance with the terms
// of the Adobe license agreement accompanying it.
// =================================================================================================

package com.adobe.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.adobe.xmp.XMPConst;
import com.adobe.xmp.XMPError;
import com.adobe.xmp.XMPException;
import com.adobe.xmp.XMPMetaFactory;
import com.adobe.xmp.XMPSchemaRegistry;
import com.adobe.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<br>
	 * 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++)