xmpnormalizer.java

flash xmp sdk,flash官方SDK

// =================================================================================================
// ADOBE SYSTEMS INCORPORATED
// Copyright 2006-2007 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.Calendar;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

import com.adobe.xmp.XMPConst;
import com.adobe.xmp.XMPDateTime;
import com.adobe.xmp.XMPError;
import com.adobe.xmp.XMPException;
import com.adobe.xmp.XMPMeta;
import com.adobe.xmp.XMPMetaFactory;
import com.adobe.xmp.XMPUtils;
import com.adobe.xmp.impl.xpath.XMPPath;
import com.adobe.xmp.impl.xpath.XMPPathParser;
import com.adobe.xmp.options.ParseOptions;
import com.adobe.xmp.options.PropertyOptions;
import com.adobe.xmp.properties.XMPAliasInfo;

/**
 * @since   Aug 18, 2006
 */
public class XMPNormalizer
{
	/** caches the correct dc-property array forms */
	private static Map dcArrayForms;
	/** init char tables */
	static
	{
		initDCArrays();
	}
	
	
	/**
	 * Hidden constructor
	 */
	private XMPNormalizer()
	{
		// EMPTY
	}

	
	/**
	 * Normalizes a raw parsed XMPMeta-Object
	 * @param xmp the raw metadata object
	 * @param options the parsing options
	 * @return Returns the normalized metadata object
	 * @throws XMPException Collects all severe processing errors. 
	 */
	static XMPMeta process(XMPMetaImpl xmp, ParseOptions options) throws XMPException 
	{
		XMPNode tree = xmp.getRoot();

		touchUpDataModel(xmp);
		moveExplicitAliases(tree, options);
		
		tweakOldXMP(tree);
		
		deleteEmptySchemas(tree);
		
		return xmp;
	}
	
	
	/**
	 * Tweak old XMP: Move an instance ID from rdf:about to the
	 * <em>xmpMM:InstanceID</em> property. An old instance ID usually looks
	 * like &quot;uuid:bac965c4-9d87-11d9-9a30-000d936b79c4&quot;, plus InDesign
	 * 3.0 wrote them like &quot;bac965c4-9d87-11d9-9a30-000d936b79c4&quot;. If
	 * the name looks like a UUID simply move it to <em>xmpMM:InstanceID</em>,
	 * don't worry about any existing <em>xmpMM:InstanceID</em>. Both will
	 * only be present when a newer file with the <em>xmpMM:InstanceID</em>
	 * property is updated by an old app that uses <em>rdf:about</em>.
	 * 
	 * @param tree the root of the metadata tree
	 * @throws XMPException Thrown if tweaking fails. 
	 */
	private static void tweakOldXMP(XMPNode tree) throws XMPException
	{
		if (tree.getName() != null  &&  tree.getName().length() >= Utils.UUID_LENGTH)
		{
			String nameStr = tree.getName().toLowerCase();
			if (nameStr.startsWith("uuid:"))
			{
				nameStr = nameStr.substring(5);
			}
			
			if (Utils.checkUUIDFormat(nameStr))
			{	
				// move UUID to xmpMM:InstanceID and remove it from the root node
				XMPPath path = XMPPathParser.expandXPath(XMPConst.NS_XMP_MM, "InstanceID");
				XMPNode idNode = XMPNodeUtils.findNode (tree, path, true, null);
				if (idNode != null)
				{
					idNode.setOptions(null);	// Clobber any existing xmpMM:InstanceID.
					idNode.setValue("uuid:" + nameStr);
					idNode.removeChildren();
					idNode.removeQualifiers();		
					tree.setName(null);
				}
				else
				{	
					throw new XMPException("Failure creating xmpMM:InstanceID",
							XMPError.INTERNALFAILURE);
				}	
			}
		}		
	}

	
	/**
	 * Visit all schemas to do general fixes and handle special cases.
	 * 
	 * @param xmp the metadata object implementation
	 * @throws XMPException Thrown if the normalisation fails.
	 */
	private static void touchUpDataModel(XMPMetaImpl xmp) throws XMPException
	{
		// make sure the DC schema is existing, because it might be needed within the normalization
		// if not touched it will be removed by removeEmptySchemas
		XMPNodeUtils.findSchemaNode(xmp.getRoot(), XMPConst.NS_DC, true);
		
		// Do the special case fixes within each schema.
		for (Iterator it = xmp.getRoot().iterateChildren(); it.hasNext();)
		{
			XMPNode currSchema = (XMPNode) it.next();
			if (XMPConst.NS_DC.equals(currSchema.getName()))
			{
				normalizeDCArrays(currSchema);
			}
			else if (XMPConst.NS_EXIF.equals(currSchema.getName()))
			{
				// Do a special case fix for exif:GPSTimeStamp.
				fixGPSTimeStamp(currSchema);
				XMPNode arrayNode = XMPNodeUtils.findChildNode(currSchema, "exif:UserComment",
						false);
				if (arrayNode != null)
				{
					repairAltText(arrayNode);
				}
			}
			else if (XMPConst.NS_DM.equals(currSchema.getName()))
			{
				// Do a special case migration of xmpDM:copyright to
				// dc:rights['x-default'].
				XMPNode dmCopyright = XMPNodeUtils.findChildNode(currSchema, "xmpDM:copyright",
						false);
				if (dmCopyright != null)
				{
					migrateAudioCopyright(xmp, dmCopyright);
				}
			}
			else if (XMPConst.NS_XMP_RIGHTS.equals(currSchema.getName()))
			{
				XMPNode arrayNode = XMPNodeUtils.findChildNode(currSchema, "xapRights:UsageTerms",
						false);			
				if (arrayNode != null)
				{	
					repairAltText(arrayNode);
				}	
			}
		}
	}
	

	/**
	 * Undo the denormalization performed by the XMP used in Acrobat 5.<br> 
	 * If a Dublin Core array had only one item, it was serialized as a simple
	 * property. <br>
	 * The <code>xml:lang</code> attribute was dropped from an
	 * <code>alt-text</code> item if the language was <code>x-default</code>.
	 * 
	 * @param dcSchema the DC schema node
	 * @throws XMPException Thrown if normalization fails
	 */
	private static void normalizeDCArrays(XMPNode dcSchema) throws XMPException
	{
		for (int i = 1; i <= dcSchema.getChildrenLength(); i++)
		{
			XMPNode currProp = dcSchema.getChild(i);
			
			PropertyOptions arrayForm = (PropertyOptions) dcArrayForms.get(currProp.getName());
			if (arrayForm == null)
			{
				continue;
			}
			else if (currProp.getOptions().isSimple())
			{	
				// create a new array and add the current property as child, 
				// if it was formerly simple 
				XMPNode newArray = new XMPNode(currProp.getName(), arrayForm);
				currProp.setName(XMPConst.ARRAY_ITEM_NAME);
				newArray.addChild(currProp);
				dcSchema.replaceChild(i, newArray);
	
				// fix language alternatives
				if (arrayForm.isArrayAltText()  &&  !currProp.getOptions().getHasLanguage())
				{
					XMPNode newLang = new XMPNode(XMPConst.XML_LANG, XMPConst.X_DEFAULT, null);
					currProp.addQualifier(newLang);
				}
			}
			else
			{
				// clear array options and add corrected array form if it has been an array before
				currProp.getOptions().setOption(
					PropertyOptions.ARRAY  |
					PropertyOptions.ARRAY_ORDERED  |
					PropertyOptions.ARRAY_ALTERNATE  |
					PropertyOptions.ARRAY_ALT_TEXT,  
					false);
				currProp.getOptions().mergeWith(arrayForm);
				
				if (arrayForm.isArrayAltText())
				{
					// applying for "dc:description", "dc:rights", "dc:title"
					repairAltText(currProp);
				}
			}
		
		}
	}

	
	/**
	 * Make sure that the array is well-formed AltText. Each item must be simple
	 * and have an "xml:lang" qualifier. If repairs are needed, keep simple
	 * non-empty items by adding the "xml:lang" with value "x-repair".
	 * @param arrayNode the property node of the array to repair.
	 * @throws XMPException Forwards unexpected exceptions.
	 */
	private static void repairAltText(XMPNode arrayNode) throws XMPException
	{
		if (arrayNode == null  ||  
			!arrayNode.getOptions().isArray())
		{
			// Already OK or not even an array.
			return;	
		}

		// fix options
		arrayNode.getOptions().setArrayOrdered(true).setArrayAlternate(true).setArrayAltText(true);
		
		for (Iterator it = arrayNode.iterateChildren(); it.hasNext();)
		{
			XMPNode currChild = (XMPNode) it.next();
			if (currChild.getOptions().isCompositeProperty())
			{
				// Delete non-simple children.
				it.remove();
			} 
			else if (!currChild.getOptions().getHasLanguage())
			{
				String childValue = currChild.getValue();
				if (childValue == null  ||  childValue.length() == 0)
				{
					// Delete empty valued children that have no xml:lang.
					it.remove();
				}
				else
				{
					// Add an xml:lang qualifier with the value "x-repair".
					XMPNode repairLang = new XMPNode(XMPConst.XML_LANG, "x-repair", null);
					currChild.addQualifier(repairLang);
				}
			}
		}		
	}
	

	/**
	 * Visit all of the top level nodes looking for aliases. If there is
	 * no base, transplant the alias subtree. If there is a base and strict
	 * aliasing is on, make sure the alias and base subtrees match.
	 * 
	 * @param tree the root of the metadata tree
	 * @param options th parsing options
	 * @throws XMPException Forwards XMP errors
	 */
	private static void moveExplicitAliases(XMPNode tree, ParseOptions options)
			throws XMPException
	{
		if (!tree.getHasAliases())
		{
			return;
		}
		tree.setHasAliases(false);
		
		boolean strictAliasing = options.getStrictAliasing();

		for (Iterator schemaIt = tree.getUnmodifiableChildren().iterator(); schemaIt.hasNext();)
		{
			XMPNode currSchema = (XMPNode) schemaIt.next();
			if (!currSchema.getHasAliases())
			{
				continue;
			}
			
			for (Iterator propertyIt = currSchema.iterateChildren(); propertyIt.hasNext();)
			{
				XMPNode currProp = (XMPNode) propertyIt.next();
				
				if (!currProp.isAlias())
				{
					continue;
				}
				
				currProp.setAlias(false);
	
				// Find the base path, look for the base schema and root node.
				XMPAliasInfo info = XMPMetaFactory.getSchemaRegistry()
						.findAlias(currProp.getName());
				if (info != null)
				{	
					// find or create schema
					XMPNode baseSchema = XMPNodeUtils.findSchemaNode(tree, info
							.getNamespace(), null, true);
					baseSchema.setImplicit(false);
					
					XMPNode baseNode = XMPNodeUtils
							.findChildNode(baseSchema, 
								info.getPrefix() + info.getPropName(), false);
					if (baseNode == null)
					{
						if (info.getAliasForm().isSimple())
						{
							// A top-to-top alias, transplant the property.
							// change the alias property name to the base name
							String qname = info.getPrefix() + info.getPropName();
							currProp.setName(qname);
							baseSchema.addChild(currProp);
							// remove the alias property
							propertyIt.remove();
						}
						else
						{
							// An alias to an array item, 
							// create the array and transplant the property.
							baseNode = new XMPNode(info.getPrefix() + info.getPropName(), info