Java tutorial
/** * The contents of this file are subject to the license and copyright * detailed in the LICENSE and NOTICE files at the root of the source * tree and available online at * * http://www.dspace.org/license/ */ package org.dspace.content.packager; import java.io.ByteArrayInputStream; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.sql.SQLException; import java.util.ArrayList; import java.util.Enumeration; import java.util.Iterator; import java.util.List; import org.apache.commons.codec.binary.Base64; import org.apache.log4j.Logger; import org.dspace.authorize.AuthorizeException; import org.dspace.content.Bitstream; import org.dspace.content.DSpaceObject; import org.dspace.content.crosswalk.AbstractPackagerWrappingCrosswalk; import org.dspace.content.crosswalk.CrosswalkException; import org.dspace.content.crosswalk.CrosswalkObjectNotSupported; import org.dspace.content.crosswalk.MetadataValidationException; import org.dspace.content.crosswalk.IngestionCrosswalk; import org.dspace.content.crosswalk.StreamIngestionCrosswalk; import org.dspace.core.ConfigurationManager; import org.dspace.core.Constants; import org.dspace.core.Context; import org.dspace.core.PluginManager; import org.jdom.Document; import org.jdom.Content; import org.jdom.Element; import org.jdom.JDOMException; import org.jdom.Namespace; import org.jdom.input.SAXBuilder; import org.jdom.output.Format; import org.jdom.output.XMLOutputter; import org.jdom.xpath.XPath; /** * <P> * Manage the METS manifest document for METS importer classes, * such as the package importer <code>org.dspace.content.packager.MetsSubmission</code> * and the federated importer <code>org.dspace.app.mets.FederatedMETSImport</code> * </P> * <P> * It can parse the METS document, build an internal model, and give the importers * access to that model. It also crosswalks * all of the descriptive and administrative metadata in the METS * manifest into the target DSpace Item, under control of the importer. * </P> * * <P> * It reads the following DSpace Configuration entries: * </P> * <UL> * <LI>Local XML schema (XSD) declarations, in the general format: * <br><code>mets.xsd.<em>identifier</em> = <em>namespace</em> <em>xsd-URL</em></code> * <br> eg. <code>mets.xsd.dc = http://purl.org/dc/elements/1.1/ dc.xsd</code> * <br>Add a separate config entry for each schema. * </LI> * <p><LI>Crosswalk plugin mappings: * These tell it the name of the crosswalk plugin to invoke for metadata sections * with a particular value of <code>MDTYPE</code> (or <code>OTHERMDTYPE</code>) * By default, the crosswalk mechanism will look for a plugin with the * same name as the metadata type (e.g. <code>"MODS"</code>, * <code>"DC"</code>). This example line invokes the <code>QDC</code> * plugin when <code>MDTYPE="DC"</code> * <br><code>mets.submission.crosswalk.DC = QDC </code> * <br> general format is: * <br><code>mets.submission.crosswalk.<em>mdType</em> = <em>pluginName</em> </code> * </LI> * </UL> * * * @author Robert Tansley * @author WeiHua Huang * @author Rita Lee * @author Larry Stone * @see org.dspace.content.packager.MetsSubmission * @see org.dspace.app.mets.FederatedMETSImport */ public class METSManifest { /** * Callback interface to retrieve data streams in mdRef elements. * "Package" or file reader returns an input stream for the * given relative path, e.g. to dereference <code>mdRef</code> elements. */ public interface Mdref { /** * Make the contents of an external resource mentioned in * an <code>mdRef</code> element available as an <code>InputStream</code>. * The implementation must use the information in the * <code>mdRef</code> element, and the state in the object that * implements this interface, to find the actual metadata content. * <p> * For example, an implementation that ingests a directory of * files on the local filesystem would get a relative pathname * out of the <code>mdRef</code> and open that file. * * @param mdRef JDOM element of mdRef in the METS manifest. * @return stream containing the metadata mentioned in mdRef. * @throws MetadataValidationException if the mdRef is unacceptable or missing required information. * @throws IOException if it is returned by services called by this method. * @throws SQLException if it is returned by services called by this method. * @throws AuthorizeException if it is returned by services called by this method. */ public InputStream getInputStream(Element mdRef) throws MetadataValidationException, PackageValidationException, IOException, SQLException, AuthorizeException; } /** log4j category */ private static final Logger log = Logger.getLogger(METSManifest.class); /** Canonical filename of METS manifest within a package or as a bitstream. */ public static final String MANIFEST_FILE = "mets.xml"; /** Prefix of DSpace configuration lines that map METS metadata type to * crosswalk plugin names. */ public static final String CONFIG_METS_PREFIX = "mets."; /** prefix of config lines identifying local XML Schema (XSD) files */ private static final String CONFIG_XSD_PREFIX = CONFIG_METS_PREFIX + "xsd."; /** Dublin core element namespace */ private static final Namespace dcNS = Namespace.getNamespace("http://purl.org/dc/elements/1.1/"); /** Dublin core term namespace (for qualified DC) */ private static final Namespace dcTermNS = Namespace.getNamespace("http://purl.org/dc/terms/"); /** METS namespace -- includes "mets" prefix for use in XPaths */ public static final Namespace metsNS = Namespace.getNamespace("mets", "http://www.loc.gov/METS/"); /** XLink namespace -- includes "xlink" prefix prefix for use in XPaths */ public static final Namespace xlinkNS = Namespace.getNamespace("xlink", "http://www.w3.org/1999/xlink"); /** root element of the current METS manifest. */ private Element mets = null; /** all mdRef elements in the manifest */ private List mdFiles = null; /** <file> elements in "original" file group (bundle) */ private List<Element> contentFiles = null; /** builder to use for mdRef streams, inherited from create() */ private SAXBuilder parser = null; /** name of packager who created this manifest object, for looking up configuration entries. */ private String configName; // Create list of local schemas at load time, since it depends only // on the DSpace configuration. private static String localSchemas; static { String dspace_dir = ConfigurationManager.getProperty("dspace.dir"); File xsdPath1 = new File(dspace_dir + "/config/schemas/"); File xsdPath2 = new File(dspace_dir + "/config/"); Enumeration<String> pe = (Enumeration<String>) ConfigurationManager.propertyNames(); StringBuffer result = new StringBuffer(); while (pe.hasMoreElements()) { // config lines have the format: // mets.xsd.{identifier} = {namespace} {xsd-URL} // e.g. // mets.xsd.dc = http://purl.org/dc/elements/1.1/ dc.xsd // (filename is relative to {dspace_dir}/config/schemas/) String key = pe.nextElement(); if (key.startsWith(CONFIG_XSD_PREFIX)) { String spec = ConfigurationManager.getProperty(key); String val[] = spec.trim().split("\\s+"); if (val.length == 2) { File xsd = new File(xsdPath1, val[1]); if (!xsd.exists()) { xsd = new File(xsdPath2, val[1]); } if (!xsd.exists()) { log.warn("Schema file not found for config entry=\"" + spec + "\""); } else { try { String u = xsd.toURL().toString(); if (result.length() > 0) { result.append(" "); } result.append(val[0]).append(" ").append(u); } catch (java.net.MalformedURLException e) { log.warn("Skipping badly formed XSD URL: " + e.toString()); } } } else { log.warn("Schema config entry has wrong format, entry=\"" + spec + "\""); } } } localSchemas = result.toString(); if (log.isDebugEnabled()) { log.debug("Got local schemas = \"" + localSchemas + "\""); } } /** * Default constructor, only called internally. * @param builder XML parser (for parsing mdRef'd files and binData) * @param mets parsed METS document */ private METSManifest(SAXBuilder builder, Element mets, String configName) { super(); this.mets = mets; parser = builder; this.configName = configName; } /** * Create a new manifest object from a serialized METS XML document. * Parse document read from the input stream, optionally validating. * @param is input stream containing serialized XML * @param validate if true, enable XML validation using schemas * in document. Also validates any sub-documents. * @throws MetadataValidationException if there is any error parsing * or validating the METS. * @return new METSManifest object. */ public static METSManifest create(InputStream is, boolean validate, String configName) throws IOException, MetadataValidationException { SAXBuilder builder = new SAXBuilder(validate); builder.setIgnoringElementContentWhitespace(true); // Set validation feature if (validate) { builder.setFeature("http://apache.org/xml/features/validation/schema", true); } // Tell the parser where local copies of schemas are, to speed up // validation. Local XSDs are identified in the configuration file. if (localSchemas.length() > 0) { builder.setProperty("http://apache.org/xml/properties/schema/external-schemaLocation", localSchemas); } // Parse the METS file Document metsDocument; try { metsDocument = builder.build(is); /*** XXX leave commented out except if needed for *** viewing the METS document that actually gets read. * * XMLOutputter outputPretty = new XMLOutputter(Format.getPrettyFormat()); * log.debug("Got METS DOCUMENT:"); * log.debug(outputPretty.outputString(metsDocument)); ****/ } catch (JDOMException je) { throw new MetadataValidationException("Error validating METS in " + is.toString(), je); } return new METSManifest(builder, metsDocument.getRootElement(), configName); } /** * Gets name of the profile to which this METS document conforms. * @return value the PROFILE attribute of mets element, or null if none. */ public String getProfile() { return mets.getAttributeValue("PROFILE"); } /** * Return the OBJID attribute of the METS manifest. * This is where the Handle URI/URN of the object can be found. * * @return OBJID attribute of METS manifest */ public String getObjID() { return mets.getAttributeValue("OBJID"); } /** * Gets all <code>file</code> elements which make up * the item's content. * @return a List of <code>Element</code>s. */ public List<Element> getContentFiles() throws MetadataValidationException { if (contentFiles != null) { return contentFiles; } contentFiles = new ArrayList<Element>(); Element fileSec = mets.getChild("fileSec", metsNS); if (fileSec != null) { Iterator fgi = fileSec.getChildren("fileGrp", metsNS).iterator(); while (fgi.hasNext()) { Element fg = (Element) fgi.next(); Iterator fi = fg.getChildren("file", metsNS).iterator(); while (fi.hasNext()) { Element f = (Element) fi.next(); contentFiles.add(f); } } } return contentFiles; } /** * Gets list of all <code>mdRef</code> elements in the METS * document. Used by ingester to e.g. check that all * required files are present. * @return a List of <code>Element</code>s. */ public List getMdFiles() throws MetadataValidationException { if (mdFiles == null) { try { // Use a special namespace with known prefix // so we get the right prefix. XPath xpath = XPath.newInstance("descendant::mets:mdRef"); xpath.addNamespace(metsNS); mdFiles = xpath.selectNodes(mets); } catch (JDOMException je) { throw new MetadataValidationException("Failed while searching for mdRef elements in manifest: ", je); } } return mdFiles; } /** * Get the "original" file element for a derived file. * Finds the original from which this was derived by matching the GROUPID * attribute that binds it to its original. For instance, the file for * a thumbnail image would have the same GROUPID as its full-size version. * <p> * NOTE: This pattern of relating derived files through the GROUPID * attribute is peculiar to the DSpace METS SIP profile, and may not be * generally useful with other sorts of METS documents. * @param file METS file element of derived file * @return file path of original or null if none found. */ public String getOriginalFilePath(Element file) { String groupID = file.getAttributeValue("GROUPID"); if (groupID == null || groupID.equals("")) { return null; } try { XPath xpath = XPath.newInstance( "mets:fileSec/mets:fileGrp[@USE=\"CONTENT\"]/mets:file[@GROUPID=\"" + groupID + "\"]"); xpath.addNamespace(metsNS); List oFiles = xpath.selectNodes(mets); if (oFiles.size() > 0) { if (log.isDebugEnabled()) { log.debug("Got ORIGINAL file for derived=" + file.toString()); } Element flocat = ((Element) oFiles.get(0)).getChild("FLocat", metsNS); if (flocat != null) { return flocat.getAttributeValue("href", xlinkNS); } } return null; } catch (JDOMException je) { log.warn("Got exception on XPATH looking for Original file, " + je.toString()); return null; } } // translate bundle name from METS to DSpace; METS may be "CONTENT" // or "ORIGINAL" for the DSpace "ORIGINAL", rest are left alone. private static String normalizeBundleName(String in) { if (in.equals("CONTENT")) { return Constants.CONTENT_BUNDLE_NAME; } else if (in.equals("MANIFESTMD")) { return Constants.METADATA_BUNDLE_NAME; } return in; } /** * Get the DSpace bundle name corresponding to the <code>USE</code> * attribute of the file group enclosing this <code>file</code> element. * * @return DSpace bundle name * @throws MetadataValidationException when there is no USE attribute on the enclosing fileGrp. */ public static String getBundleName(Element file) throws MetadataValidationException { Element fg = file.getParentElement(); String fgUse = fg.getAttributeValue("USE"); if (fgUse == null) { throw new MetadataValidationException( "Invalid METS Manifest: every fileGrp element must have a USE attribute."); } return normalizeBundleName(fgUse); } /** * Get the "local" file name of this <code>file</code> or <code>mdRef</code> element. * By "local" we mean the reference to the actual resource containing * the data for this file, e.g. a relative path within a Zip or tar archive * if the METS is serving as a manifest for that sort of package. * @return "local" file name (i.e. relative to package or content * directory) corresponding to this <code>file</code> or <code>mdRef</code> element. * @throws MetadataValidationException when there is not enough information to find a resource identifier. */ public static String getFileName(Element file) throws MetadataValidationException { Element ref; if (file.getName().equals("file")) { ref = file.getChild("FLocat", metsNS); if (ref == null) { // check for forbidden FContent child first: if (file.getChild("FContent", metsNS) == null) { throw new MetadataValidationException( "Invalid METS Manifest: Every file element must have FLocat child."); } else { throw new MetadataValidationException( "Invalid METS Manifest: file element has forbidden FContent child, only FLocat is allowed."); } } } else if (file.getName().equals("mdRef")) { ref = file; } else { throw new MetadataValidationException( "getFileName() called with recognized element type: " + file.toString()); } String loctype = ref.getAttributeValue("LOCTYPE"); if (loctype != null && loctype.equals("URL")) { String result = ref.getAttributeValue("href", xlinkNS); if (result == null) { throw new MetadataValidationException( "Invalid METS Manifest: FLocat/mdRef is missing the required xlink:href attribute."); } return result; } throw new MetadataValidationException( "Invalid METS Manifest: FLocat/mdRef does not have LOCTYPE=\"URL\" attribute."); } /** * Returns file element corresponding to primary bitstream. * There is <i>ONLY</i> a primary bitstream if the first {@code div} under * first {@code structMap} has an {@code fptr}. * * @return file element of Item's primary bitstream, or null if there is none. */ public Element getPrimaryOrLogoBitstream() throws MetadataValidationException { Element objDiv = getObjStructDiv(); Element fptr = objDiv.getChild("fptr", metsNS); if (fptr == null) { return null; } String id = fptr.getAttributeValue("FILEID"); if (id == null) { throw new MetadataValidationException( "fptr for Primary Bitstream is missing the required FILEID attribute."); } Element result = getElementByXPath("descendant::mets:file[@ID=\"" + id + "\"]", false); if (result == null) { throw new MetadataValidationException( "Cannot find file element for Primary Bitstream: looking for ID=" + id); } return result; } /** * Get the metadata type from within a *mdSec element. * @return metadata type name. */ public String getMdType(Element mdSec) throws MetadataValidationException { Element md = mdSec.getChild("mdRef", metsNS); if (md == null) { md = mdSec.getChild("mdWrap", metsNS); } if (md == null) { throw new MetadataValidationException( "Invalid METS Manifest: ?mdSec element has neither mdRef nor mdWrap child."); } String result = md.getAttributeValue("MDTYPE"); if (result != null && result.equals("OTHER")) { result = md.getAttributeValue("OTHERMDTYPE"); } if (result == null) { throw new MetadataValidationException( "Invalid METS Manifest: " + md.getName() + " has no MDTYPE or OTHERMDTYPE attribute."); } return result; } /** * Returns MIME type of metadata content, if available. * @return MIMEtype word, or null if none is available. */ public String getMdContentMimeType(Element mdSec) throws MetadataValidationException { Element mdWrap = mdSec.getChild("mdWrap", metsNS); if (mdWrap != null) { String mimeType = mdWrap.getAttributeValue("MIMETYPE"); if (mimeType == null && mdWrap.getChild("xmlData", metsNS) != null) { mimeType = "text/xml"; } return mimeType; } Element mdRef = mdSec.getChild("mdRef", metsNS); if (mdRef != null) { return mdRef.getAttributeValue("MIMETYPE"); } return null; } /** * Return contents of *md element as List of XML Element objects. * Gets content, dereferencing mdRef if necessary, or decoding and parsing * a binData that contains XML. * @return contents of metadata section, or empty list if no XML content is available. * @throws MetadataValidationException if METS is invalid, or there is an error parsing the XML. */ public List<Element> getMdContentAsXml(Element mdSec, Mdref callback) throws MetadataValidationException, PackageValidationException, IOException, SQLException, AuthorizeException { try { // XXX sanity check: if this has more than one child, consider it // an error since we cannot deal with more than one mdRef|mdWrap // child. This may be considered a bug and need to be fixed, // so it's best to bring it to the attention of users. List mdc = mdSec.getChildren(); if (mdc.size() > 1) { // XXX scaffolding for debugging diagnosis; at least one // XML parser stupidly includes newlines in prettyprinting // as text content objects.. String id = mdSec.getAttributeValue("ID"); StringBuffer sb = new StringBuffer(); for (Iterator mi = mdc.iterator(); mi.hasNext();) { sb.append(", ").append(((Content) mi.next()).toString()); } throw new MetadataValidationException("Cannot parse METS with " + mdSec.getQualifiedName() + " element that contains more than one child, size=" + String.valueOf(mdc.size()) + ", ID=" + id + "Kids=" + sb.toString()); } Element mdRef = null; Element mdWrap = mdSec.getChild("mdWrap", metsNS); if (mdWrap != null) { Element xmlData = mdWrap.getChild("xmlData", metsNS); if (xmlData == null) { Element bin = mdWrap.getChild("binData", metsNS); if (bin == null) { throw new MetadataValidationException( "Invalid METS Manifest: mdWrap element with neither xmlData nor binData child."); } // if binData is actually XML, return it; otherwise ignore. else { String mimeType = mdWrap.getAttributeValue("MIMETYPE"); if (mimeType != null && mimeType.equalsIgnoreCase("text/xml")) { byte value[] = Base64.decodeBase64(bin.getText().getBytes()); Document mdd = parser.build(new ByteArrayInputStream(value)); List<Element> result = new ArrayList<Element>(1); result.add(mdd.getRootElement()); return result; } else { log.warn("Ignoring binData section because MIMETYPE is not XML, but: " + mimeType); return new ArrayList<Element>(0); } } } else { return xmlData.getChildren(); } } else { mdRef = mdSec.getChild("mdRef", metsNS); if (mdRef != null) { String mimeType = mdRef.getAttributeValue("MIMETYPE"); if (mimeType != null && mimeType.equalsIgnoreCase("text/xml")) { Document mdd = parser.build(callback.getInputStream(mdRef)); List<Element> result = new ArrayList<Element>(1); result.add(mdd.getRootElement()); return result; } else { log.warn("Ignoring mdRef section because MIMETYPE is not XML, but: " + mimeType); return new ArrayList<Element>(0); } } else { throw new MetadataValidationException( "Invalid METS Manifest: ?mdSec element with neither mdRef nor mdWrap child."); } } } catch (JDOMException je) { throw new MetadataValidationException( "Error parsing or validating metadata section in mdRef or binData within " + mdSec.toString(), je); } } /** * Return contents of *md element as stream. * Gets content, dereferencing mdRef if necessary, or decoding * a binData element if necessary. * @return Stream containing contents of metadata section. Never returns null. * @throws MetadataValidationException if METS format does not contain any metadata. */ public InputStream getMdContentAsStream(Element mdSec, Mdref callback) throws MetadataValidationException, PackageValidationException, IOException, SQLException, AuthorizeException { Element mdRef = null; Element mdWrap = mdSec.getChild("mdWrap", metsNS); if (mdWrap != null) { Element xmlData = mdWrap.getChild("xmlData", metsNS); if (xmlData == null) { Element bin = mdWrap.getChild("binData", metsNS); if (bin == null) { throw new MetadataValidationException( "Invalid METS Manifest: mdWrap element with neither xmlData nor binData child."); } else { byte value[] = Base64.decodeBase64(bin.getText().getBytes()); return new ByteArrayInputStream(value); } } else { XMLOutputter outputPretty = new XMLOutputter(Format.getPrettyFormat()); return new ByteArrayInputStream(outputPretty.outputString(xmlData.getChildren()).getBytes()); } } else { mdRef = mdSec.getChild("mdRef", metsNS); if (mdRef != null) { return callback.getInputStream(mdRef); } else { throw new MetadataValidationException( "Invalid METS Manifest: ?mdSec element with neither mdRef nor mdWrap child."); } } } /** * Return the {@code <div>} which describes this DSpace Object (and its contents) * from the {@code <structMap>}. In all cases, this is the first {@code <div>} * in the first {@code <structMap>}. * * @return Element which is the DSpace Object Contents {@code <div>} * @throws MetadataValidationException */ public Element getObjStructDiv() throws MetadataValidationException { //get first <structMap> Element sm = mets.getChild("structMap", metsNS); if (sm == null) { throw new MetadataValidationException("METS document is missing the required structMap element."); } //get first <div> Element result = sm.getChild("div", metsNS); if (result == null) { throw new MetadataValidationException( "METS document is missing the required first div element in first structMap."); } if (log.isDebugEnabled()) { log.debug("Got getObjStructDiv result=" + result.toString()); } return (Element) result; } /** * Get an array of child object {@code <div>}s from the METS Manifest {@code <structMap>}. * These {@code <div>}s reference the location of any child objects METS manifests. * * @return a List of {@code Element}s, each a {@code <div>}. May be empty but NOT null. * @throws MetadataValidationException */ public List getChildObjDivs() throws MetadataValidationException { //get the <div> in <structMap> which describes the current object's contents Element objDiv = getObjStructDiv(); //get the child <div>s -- these should reference the child METS manifest return objDiv.getChildren("div", metsNS); } /** * Retrieve the file paths for the children objects' METS Manifest files. * These file paths are located in the {@code <mptr>} where @LOCTYPE=URL * * @return a list of Strings, corresponding to relative file paths of children METS manifests * @throws MetadataValidationException */ public String[] getChildMetsFilePaths() throws MetadataValidationException { //get our child object <div>s List childObjDivs = getChildObjDivs(); List<String> childPathList = new ArrayList<String>(); if (childObjDivs != null && !childObjDivs.isEmpty()) { Iterator childIterator = childObjDivs.iterator(); //For each Div, we want to find the underlying <mptr> with @LOCTYPE=URL while (childIterator.hasNext()) { Element childDiv = (Element) childIterator.next(); //get all child <mptr>'s List childMptrs = childDiv.getChildren("mptr", metsNS); if (childMptrs != null && !childMptrs.isEmpty()) { Iterator mptrIterator = childMptrs.iterator(); //For each mptr, we want to find the one with @LOCTYPE=URL while (mptrIterator.hasNext()) { Element mptr = (Element) mptrIterator.next(); String locType = mptr.getAttributeValue("LOCTYPE"); //if @LOCTYPE=URL, then capture @xlink:href as the METS Manifest file path if (locType != null && locType.equals("URL")) { String filePath = mptr.getAttributeValue("href", xlinkNS); if (filePath != null && filePath.length() > 0) { childPathList.add(filePath); } } } //end <mptr> loop } //end if <mptr>'s exist } //end child <div> loop } //end if child <div>s exist String[] childPaths = new String[childPathList.size()]; childPaths = (String[]) childPathList.toArray(childPaths); return childPaths; } /** * Return the reference to the Parent Object from the "Parent" {@code <structMap>}. * This parent object is the owner of current object. * * @return Link to the Parent Object (this is the Handle of that Parent) * @throws MetadataValidationException */ public String getParentOwnerLink() throws MetadataValidationException { //get a list of our structMaps List<Element> childStructMaps = mets.getChildren("structMap", metsNS); Element parentStructMap = null; // find the <structMap LABEL='Parent'> if (!childStructMaps.isEmpty()) { for (Element structMap : childStructMaps) { String label = structMap.getAttributeValue("LABEL"); if (label != null && label.equalsIgnoreCase("Parent")) { parentStructMap = structMap; break; } } } if (parentStructMap == null) { throw new MetadataValidationException( "METS document is missing the required structMap[@LABEL='Parent'] element."); } //get first <div> Element linkDiv = parentStructMap.getChild("div", metsNS); if (linkDiv == null) { throw new MetadataValidationException( "METS document is missing the required first div element in structMap[@LABEL='Parent']."); } //the link is in the <mptr> in the @xlink:href attribute Element mptr = linkDiv.getChild("mptr", metsNS); if (mptr != null) { return mptr.getAttributeValue("href", xlinkNS); } //return null if we couldn't find the link return null; } // return a single Element node found by one-off path. // use only when path varies each time you call it. private Element getElementByXPath(String path, boolean nullOk) throws MetadataValidationException { try { XPath xpath = XPath.newInstance(path); xpath.addNamespace(metsNS); xpath.addNamespace(xlinkNS); Object result = xpath.selectSingleNode(mets); if (result == null && nullOk) { return null; } else if (result instanceof Element) { return (Element) result; } else { throw new MetadataValidationException( "METSManifest: Failed to resolve XPath, path=\"" + path + "\""); } } catch (JDOMException je) { throw new MetadataValidationException("METSManifest: Failed to resolve XPath, path=\"" + path + "\"", je); } } // Find crosswalk for the indicated metadata type (e.g. "DC", "MODS") private Object getCrosswalk(String type, Class clazz) { /** * Allow DSpace Config to map the metadata type to a * different crosswalk name either per-packager or for METS * in general. First, look for config key like: * mets.<packagerName>.ingest.crosswalk.MDNAME = XWALKNAME * then try * mets.default.ingest.crosswalk.MDNAME = XWALKNAME */ String xwalkName = ConfigurationManager .getProperty(CONFIG_METS_PREFIX + configName + ".ingest.crosswalk." + type); if (xwalkName == null) { xwalkName = ConfigurationManager.getProperty(CONFIG_METS_PREFIX + "default.ingest.crosswalk." + type); if (xwalkName == null) { xwalkName = type; } } return PluginManager.getNamedPlugin(clazz, xwalkName); } /** * Gets all dmdSec elements containing metadata for the DSpace Item. * * @return array of Elements, each a dmdSec. May be empty but NOT null. * @throws MetadataValidationException if the METS is missing a reference to item-wide * DMDs in the correct place. */ public Element[] getItemDmds() throws MetadataValidationException { // div@DMDID is actually IDREFS, a space-separated list of IDs: Element objDiv = getObjStructDiv(); String dmds = objDiv.getAttributeValue("DMDID"); if (dmds == null) { throw new MetadataValidationException( "Invalid METS: Missing reference to Item descriptive metadata, first div on first structmap must have a DMDID attribute."); } return getDmdElements(dmds); } /** * Gets all dmdSec elements from a space separated list * * @param dmdList space-separated list of DMDIDs * @return array of Elements, each a dmdSec. May be empty but NOT null. * @throws MetadataValidationException if the METS is missing a reference to item-wide * DMDs in the correct place. */ public Element[] getDmdElements(String dmdList) throws MetadataValidationException { if (dmdList != null && !dmdList.isEmpty()) { String dmdID[] = dmdList.split("\\s+"); Element result[] = new Element[dmdID.length]; for (int i = 0; i < dmdID.length; ++i) { result[i] = getElementByXPath("mets:dmdSec[@ID=\"" + dmdID[i] + "\"]", false); } return result; } else { return new Element[0]; } } /** * Return rights metadata section(s) relevant to item as a whole. * @return array of rightsMd elements, possibly empty but never null. * @throws MetadataValidationException if METS is invalid, e.g. referenced amdSec is missing. */ public Element[] getItemRightsMD() throws MetadataValidationException { // div@ADMID is actually IDREFS, a space-separated list of IDs: Element objDiv = getObjStructDiv(); String amds = objDiv.getAttributeValue("ADMID"); if (amds == null) { if (log.isDebugEnabled()) { log.debug("getItemRightsMD: No ADMID references found."); } return new Element[0]; } String amdID[] = amds.split("\\s+"); List<Element> resultList = new ArrayList<Element>(); for (int i = 0; i < amdID.length; ++i) { List rmds = getElementByXPath("mets:amdSec[@ID=\"" + amdID[i] + "\"]", false).getChildren("rightsMD", metsNS); if (rmds.size() > 0) { resultList.addAll(rmds); } } return resultList.toArray(new Element[resultList.size()]); } /** * Invokes appropriate crosswalks on Item-wide descriptive metadata. */ public void crosswalkItemDmd(Context context, PackageParameters params, DSpaceObject dso, Element dmdSec, Mdref callback) throws MetadataValidationException, PackageValidationException, CrosswalkException, IOException, SQLException, AuthorizeException { crosswalkXmd(context, params, dso, dmdSec, callback); } /** * Crosswalk all technical and source metadata sections that belong * to the whole object. * @throws MetadataValidationException if METS is invalid, e.g. referenced amdSec is missing. */ public void crosswalkObjectOtherAdminMD(Context context, PackageParameters params, DSpaceObject dso, Mdref callback) throws MetadataValidationException, PackageValidationException, CrosswalkException, IOException, SQLException, AuthorizeException { for (String amdID : getAmdIDs()) { Element amdSec = getElementByXPath("mets:amdSec[@ID=\"" + amdID + "\"]", false); for (Iterator ti = amdSec.getChildren("techMD", metsNS).iterator(); ti.hasNext();) { crosswalkXmd(context, params, dso, (Element) ti.next(), callback); } for (Iterator ti = amdSec.getChildren("digiprovMD", metsNS).iterator(); ti.hasNext();) { crosswalkXmd(context, params, dso, (Element) ti.next(), callback); } for (Iterator ti = amdSec.getChildren("rightsMD", metsNS).iterator(); ti.hasNext();) { crosswalkXmd(context, params, dso, (Element) ti.next(), callback); } } } /** * Just crosswalk the sourceMD sections; used to set the handle and parent of AIP. * @return true if any metadata section was actually crosswalked, false otherwise */ public boolean crosswalkObjectSourceMD(Context context, PackageParameters params, DSpaceObject dso, Mdref callback) throws MetadataValidationException, PackageValidationException, CrosswalkException, IOException, SQLException, AuthorizeException { boolean result = false; for (String amdID : getAmdIDs()) { Element amdSec = getElementByXPath("mets:amdSec[@ID=\"" + amdID + "\"]", false); for (Iterator ti = amdSec.getChildren("sourceMD", metsNS).iterator(); ti.hasNext();) { crosswalkXmd(context, params, dso, (Element) ti.next(), callback); result = true; } } return result; } /** * Get an aray of all AMDID values for this object * * @return * @throws MetadataValidationException */ private String[] getAmdIDs() throws MetadataValidationException { // div@ADMID is actually IDREFS, a space-separated list of IDs: Element objDiv = getObjStructDiv(); String amds = objDiv.getAttributeValue("ADMID"); if (amds == null) { if (log.isDebugEnabled()) { log.debug("crosswalkObjectTechMD: No ADMID references found."); } return new String[0]; } return amds.split("\\s+"); } // Crosswalk *any* kind of metadata section - techMD, rightsMD, etc. private void crosswalkXmd(Context context, PackageParameters params, DSpaceObject dso, Element xmd, Mdref callback) throws MetadataValidationException, PackageValidationException, CrosswalkException, IOException, SQLException, AuthorizeException { String type = getMdType(xmd); //First, try to find the IngestionCrosswalk to use IngestionCrosswalk xwalk = (IngestionCrosswalk) getCrosswalk(type, IngestionCrosswalk.class); // If metadata is not simply applicable to object, // let it go with a warning. try { // If we found the IngestionCrosswalk, crosswalk our XML-based content if (xwalk != null) { // Check if our Crosswalk actually wraps another Packager Plugin if (xwalk instanceof AbstractPackagerWrappingCrosswalk) { // If this crosswalk wraps another Packager Plugin, we can pass it our Packaging Parameters // (which essentially allow us to customize the ingest process of the crosswalk) AbstractPackagerWrappingCrosswalk wrapper = (AbstractPackagerWrappingCrosswalk) xwalk; wrapper.setPackagingParameters(params); } xwalk.ingest(context, dso, getMdContentAsXml(xmd, callback)); } // Otherwise, try stream-based crosswalk else { StreamIngestionCrosswalk sxwalk = (StreamIngestionCrosswalk) getCrosswalk(type, StreamIngestionCrosswalk.class); if (sxwalk != null) { // Check if our Crosswalk actually wraps another Packager Plugin if (sxwalk instanceof AbstractPackagerWrappingCrosswalk) { // If this crosswalk wraps another Packager Plugin, we can pass it our Packaging Parameters // (which essentially allow us to customize the ingest process of the crosswalk) AbstractPackagerWrappingCrosswalk wrapper = (AbstractPackagerWrappingCrosswalk) sxwalk; wrapper.setPackagingParameters(params); } // If we found a Stream-based crosswalk that matches, we now want to // locate the stream we are crosswalking. This stream should be // references in METS via an <mdRef> element // (which is how METS references external files) Element mdRef = xmd.getChild("mdRef", metsNS); if (mdRef != null) { InputStream in = null; try { in = callback.getInputStream(mdRef); sxwalk.ingest(context, dso, in, mdRef.getAttributeValue("MIMETYPE")); } finally { if (in != null) { in.close(); } } } // If we couldn't find an <mdRef>, then we'll try an <mdWrap> // with a <binData> element instead. // (this is how METS wraps embedded base64-encoded content streams) else { Element mdWrap = xmd.getChild("mdWrap", metsNS); if (mdWrap != null) { Element bin = mdWrap.getChild("binData", metsNS); if (bin == null) { throw new MetadataValidationException( "Invalid METS Manifest: mdWrap element for streaming crosswalk without binData child."); } else { byte value[] = Base64.decodeBase64(bin.getText().getBytes()); sxwalk.ingest(context, dso, new ByteArrayInputStream(value), mdWrap.getAttributeValue("MIMETYPE")); } } else { throw new MetadataValidationException( "Cannot process METS Manifest: " + "Metadata of type=" + type + " requires a reference to a stream (mdRef), which was not found in " + xmd.getName()); } } } else { throw new MetadataValidationException("Cannot process METS Manifest: " + "No crosswalk found for contents of " + xmd.getName() + " element, MDTYPE=" + type); } } } catch (CrosswalkObjectNotSupported e) { log.warn("Skipping metadata section " + xmd.getName() + ", type=" + type + " inappropriate for this type of object: Object=" + dso.toString() + ", error=" + e.toString()); } } /** * Crosswalk the metadata associated with a particular <code>file</code> * element into the bitstream it corresponds to. * @param context a dspace context. * @param params any PackageParameters which may affect how bitstreams are crosswalked * @param bitstream bitstream target of the crosswalk * @param fileId value of ID attribute in the file element responsible * for the contents of that bitstream. * @param callback ??? */ public void crosswalkBitstream(Context context, PackageParameters params, Bitstream bitstream, String fileId, Mdref callback) throws MetadataValidationException, PackageValidationException, CrosswalkException, IOException, SQLException, AuthorizeException { Element file = getElementByXPath("descendant::mets:file[@ID=\"" + fileId + "\"]", false); if (file == null) { throw new MetadataValidationException( "Failed in Bitstream crosswalk, Could not find file element with ID=" + fileId); } // In DSpace METS SIP spec, admin metadata is only "highly // recommended", not "required", so it is OK if there is no ADMID. String amds = file.getAttributeValue("ADMID"); if (amds == null) { log.warn("Got no bitstream ADMID, file@ID=" + fileId); return; } String amdID[] = amds.split("\\s+"); for (int i = 0; i < amdID.length; ++i) { Element amdSec = getElementByXPath("mets:amdSec[@ID=\"" + amdID[i] + "\"]", false); for (Iterator ti = amdSec.getChildren("techMD", metsNS).iterator(); ti.hasNext();) { crosswalkXmd(context, params, bitstream, (Element) ti.next(), callback); } for (Iterator ti = amdSec.getChildren("sourceMD", metsNS).iterator(); ti.hasNext();) { crosswalkXmd(context, params, bitstream, (Element) ti.next(), callback); } } } /** * @return root element of METS document. */ public Element getMets() { return mets; } /** * Return entire METS document as an inputStream * * @return entire METS document as a stream */ public InputStream getMetsAsStream() { XMLOutputter outputPretty = new XMLOutputter(Format.getPrettyFormat()); return new ByteArrayInputStream(outputPretty.outputString(mets).getBytes()); } }