org.dspace.content.crosswalk
Class AIPTechMDCrosswalk

java.lang.Object
  org.dspace.content.crosswalk.AIPTechMDCrosswalk

All Implemented Interfaces:

DisseminationCrosswalk, IngestionCrosswalk

public class AIPTechMDCrosswalk
extends Object
implements DisseminationCrosswalk, IngestionCrosswalk

Crosswalk of technical metadata for DSpace AIP. This is only intended for use by the METS AIP packager. It borrows the DIM XML format and DC field names, although it abuses the meaning of Dublin Core terms and qualifiers because this format is ONLY FOR DSPACE INTERNAL USE AND INGESTION. It is needed to record a complete and accurate image of all of the attributes an object has in the RDBMS. It encodes the following common properties of all archival objects: identifier.uri -- persistent identifier of object in URI form (e.g. Handle URN) relation.isPartOf -- persistent identifier of object's parent in URI form (e.g. Handle URN) relation.isReferencedBy -- if relevant, persistent identifier of other objects that map this one as a child. May repeat. There may also be other fields, depending on the type of object, which encode attributes that are not part of the descriptive metadata and are not adequately covered by other technical MD formats (i.e. PREMIS). Configuration entries: aip.ingest.createEperson -- boolean, create EPerson for Submitter automatically, on ingest, if it doesn't exist.

Version:

$Revision: 1.2 $

Author:

Larry Stone

Field Summary

Fields inherited from interface org.dspace.content.crosswalk.DisseminationCrosswalk

XSI_NS

Constructor Summary

AIPTechMDCrosswalk()

Method Summary

boolean	canDisseminate(DSpaceObject dso) Predicate: Can this disseminator crosswalk the given object.
org.jdom.Element	disseminateElement(DSpaceObject dso) Execute crosswalk, returning one XML root element as a JDOM Element object.
List<org.jdom.Element>	disseminateList(DSpaceObject dso) Execute crosswalk, returning List of XML elements.
org.jdom.Namespace[]	getNamespaces() Get XML namespaces of the elements this crosswalk may return.
String	getSchemaLocation() Get the XML Schema location(s) of the target metadata format.
void	ingest(Context context, DSpaceObject dso, org.jdom.Element root) Ingest a whole document.
void	ingest(Context context, DSpaceObject dso, List<org.jdom.Element> dimList) Translate metadata with XSL stylesheet and ingest it.
boolean	preferList() Predicate: Does this disseminator prefer to return a list of Elements, rather than a single root Element?

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AIPTechMDCrosswalk

public AIPTechMDCrosswalk()

Method Detail

getNamespaces

public org.jdom.Namespace[] getNamespaces()

Get XML namespaces of the elements this crosswalk may return. Returns the XML namespaces (as JDOM objects) of the root element.

Specified by:

getNamespaces in interface DisseminationCrosswalk

Returns:

array of namespaces, which may be empty.

getSchemaLocation

public String getSchemaLocation()

Get the XML Schema location(s) of the target metadata format. Returns the string value of the xsi:schemaLocation attribute that should be applied to the generated XML.

It may return the empty string if no schema is known, but crosswalk authors are strongly encouraged to implement this call so their output XML can be validated correctly.

Specified by:

getSchemaLocation in interface DisseminationCrosswalk

Returns:

SchemaLocation string, including URI namespace, followed by whitespace and URI of XML schema document, or empty string if unknown.

canDisseminate

public boolean canDisseminate(DSpaceObject dso)

Predicate: Can this disseminator crosswalk the given object. Needed by OAI-PMH server implementation.

Specified by:

canDisseminate in interface DisseminationCrosswalk

Parameters:

dso - dspace object, e.g. an Item.

Returns:

true when disseminator is capable of producing metadata.

preferList

public boolean preferList()

Predicate: Does this disseminator prefer to return a list of Elements, rather than a single root Element?

Some metadata formats have an XML schema without a root element, for example, the Dublin Core and Qualified Dublin Core formats. This would be true for a crosswalk into QDC, since it would "prefer" to return a list, since any root element it has to produce would have to be part of a nonstandard schema. In most cases your implementation will want to return false

Specified by:

preferList in interface DisseminationCrosswalk

Returns:

true when disseminator prefers you call disseminateList().

disseminateList

public List<org.jdom.Element> disseminateList(DSpaceObject dso)
                                       throws CrosswalkException,
                                              IOException,
                                              SQLException,
                                              AuthorizeException

Execute crosswalk, returning List of XML elements. Returns a List of JDOM Element objects representing the XML produced by the crosswalk. This is typically called when a list of fields is desired, e.g. for embedding in a METS document xmlData field.

When there are no results, an empty list is returned, but never null.

Specified by:

disseminateList in interface DisseminationCrosswalk

Parameters:

dso - the DSpace Object whose metadata to export.

Returns:

results of crosswalk as list of XML elements.

Throws:

CrosswalkInternalException - (CrosswalkException) failure of the crosswalk itself.

CrosswalkObjectNotSupported - (CrosswalkException) Cannot crosswalk this kind of DSpace object.

IOException - I/O failure in services this calls

SQLException - Database failure in services this calls

AuthorizeException - current user not authorized for this operation.

CrosswalkException

disseminateElement

public org.jdom.Element disseminateElement(DSpaceObject dso)
                                    throws CrosswalkException,
                                           IOException,
                                           SQLException,
                                           AuthorizeException

Execute crosswalk, returning one XML root element as a JDOM Element object. This is typically the root element of a document.

Specified by:

disseminateElement in interface DisseminationCrosswalk

Parameters:

dso - the DSpace Object whose metadata to export.

Returns:

root Element of the target metadata, never null

Throws:

CrosswalkInternalException - (CrosswalkException) failure of the crosswalk itself.

CrosswalkObjectNotSupported - (CrosswalkException) Cannot crosswalk this kind of DSpace object.

IOException - I/O failure in services this calls

SQLException - Database failure in services this calls

AuthorizeException - current user not authorized for this operation.

CrosswalkException

ingest

public void ingest(Context context,
                   DSpaceObject dso,
                   org.jdom.Element root)
            throws CrosswalkException,
                   IOException,
                   SQLException,
                   AuthorizeException

Ingest a whole document. Build Document object around root element, and feed that to the transformation, since it may get handled differently than a List of metadata elements.

Specified by:

ingest in interface IngestionCrosswalk

Parameters:

context - DSpace context.

dso - DSpace Object (usually an Item) to which new metadata gets attached.

root - root Element of metadata document.

Throws:

CrosswalkInternalException - (CrosswalkException) failure of the crosswalk itself.

CrosswalkObjectNotSupported - (CrosswalkException) Cannot crosswalk into this kind of DSpace object.

MetadataValidationException - (CrosswalkException) metadata format was not acceptable or missing required elements.

IOException - I/O failure in services this calls

SQLException - Database failure in services this calls

AuthorizeException - current user not authorized for this operation.

CrosswalkException

ingest

public void ingest(Context context,
                   DSpaceObject dso,
                   List<org.jdom.Element> dimList)
            throws CrosswalkException,
                   IOException,
                   SQLException,
                   AuthorizeException

Translate metadata with XSL stylesheet and ingest it. Translation produces a list of DIM "field" elements; these correspond directly to Item.addMetadata() calls so they are simply executed.

Specified by:

ingest in interface IngestionCrosswalk

Parameters:

context - DSpace context.

dso - DSpace Object (Item, Bitstream, etc) to which new metadata gets attached.

dimList - List of XML Elements of metadata

Throws:

CrosswalkInternalException - (CrosswalkException) failure of the crosswalk itself.

CrosswalkObjectNotSupported - (CrosswalkException) Cannot crosswalk into this kind of DSpace object.

MetadataValidationException - (CrosswalkException) metadata format was not acceptable or missing required elements.

IOException - I/O failure in services this calls

SQLException - Database failure in services this calls

AuthorizeException - current user not authorized for this operation.

CrosswalkException