How to use

ExternalReferenceSPI

in

net.sf.taverna.t2.reference

protected InputStream getAsStream(ReferenceService referenceService, T2Reference t2Reference) {
  Identified identified = referenceService.resolveIdentifier(t2Reference, null, null);
  if (identified instanceof ReferenceSet) {
    ExternalReferenceSPI ref = ((ReferenceSet) identified).getExternalReferences().iterator().next();
    return ref.openStream(invocationContext);
  }
  return null;
}

  public int compare(ExternalReferenceSPI o1,
      ExternalReferenceSPI o2) {
    return (int) (o1.getResolutionCost() - o2
        .getResolutionCost());
  }
});

  || ers.getResolutionCost() < cheapestReferenceCost) {
cheapestReference = ers;
cheapestReferenceCost = ers.getResolutionCost();
  .openStream(context), cheapestReference.getDataNature(), cheapestReference.getCharset());

  || ers.getResolutionCost() < cheapestReferenceCost) {
cheapestReference = ers;
cheapestReferenceCost = ers.getResolutionCost();
  .openStream(context));

  if (externalReference.getDataNature().equals(ReferencedDataNature.TEXT)) {
    break;
FileOutputStream fileOutputStream = new FileOutputStream(targetFile);
InputStream openStream = externalReferences.get(0)
    .openStream(context);
IOUtils.copyLarge(openStream, fileOutputStream);
try {

refElement.addContent(externalReference.getDataNature()
    .toString());
element.addContent(refElement);

/**
 * Construct a new ReferenceSetImpl with the given set of external
 * references and identifier.
 * 
 * @param references
 *            the set of ExternalReferenceSPI which this reference set
 *            should contain initially
 * @param id
 *            the T2Reference to use, must be an instance of
 *            ReferenceSetT2ReferenceImpl so hibernate can make use of it as
 *            a compound primary key component
 */
public ReferenceSetImpl(Set<ExternalReferenceSPI> references,
    T2ReferenceImpl id) {
  setTypedId(id);
  this.externalReferences = references;
  
  //  Should be at least one - otherwise we cannot calculate the data size
  if (externalReferences != null && externalReferences.size() > 0){		
    // Just take the first ExternalReferenceSPI returned
    ExternalReferenceSPI externalReferenceSPI = externalReferences.toArray(new ExternalReferenceSPI[0])[0];
    approximateSizeInBytes = externalReferenceSPI.getApproximateSizeInBytes();
  }

}

  || ers.getResolutionCost() < cheapestReferenceCost) {
cheapestReference = ers;
cheapestReferenceCost = ers.getResolutionCost();
  .openStream(context));

ReferencedDataNature erDataNature = ers.getDataNature();
if (!erDataNature.equals(ReferencedDataNature.UNKNOWN)) {
  dataNature = erDataNature;

public static MagicMatch getMagicMatch(ExternalReferenceSPI externalReference, InvocationContext context) {
  InputStream inputStream = externalReference.openStream(context);
  byte[] bytes = null;
  MagicMatch magicMatch = null;

  public int compare(ExternalReferenceSPI o1,
      ExternalReferenceSPI o2) {
    return (int) (o1.getResolutionCost() - o2
        .getResolutionCost());
  }
});

ReferencedDataNature erDataNature = ers.getDataNature();
if (!erDataNature.equals(ReferencedDataNature.UNKNOWN)) {
  dataNature = erDataNature;

private String getMimeType(ExternalReferenceSPI externalReference, InvocationContext context) {
  if (!mimeTypes.containsKey(externalReference)) {
    InputStream inputStream = externalReference.openStream(context);
    try {
      byte[] bytes = new byte[64];
      inputStream.read(bytes);
      mimeTypes.put(externalReference, Magic.getMagicMatch(bytes, true).getMimeType());
    } catch (IOException e) {
      e.printStackTrace();
      logger.debug("Failed to read from stream to determine mimetype", e);
    } catch (MagicParseException e) {
      e.printStackTrace();
      logger.debug("Error calling mime magic", e);
    } catch (MagicMatchNotFoundException e) {
      e.printStackTrace();
      logger.debug("Error calling mime magic", e);
    } catch (MagicException e) {
      e.printStackTrace();
      logger.debug("Error calling mime magic", e);
    } finally {
      try {
        inputStream.close();
      } catch (IOException e) {
        e.printStackTrace();
        logger.debug("Failed to close stream after determining mimetype", e);
      }
    }
  }
  return mimeTypes.get(externalReference);
}

  public int compare(ExternalReferenceSPI o1,
      ExternalReferenceSPI o2) {
    return (int) (o1.getResolutionCost() - o2
        .getResolutionCost());
  }
});

if (initialBuilder != null && sourceReference != null) {
  ExternalReferenceSPI builtReference = initialBuilder
      .createReference(sourceReference.openStream(context),
          context);
  results.add(builtReference);

  public int compare(ExternalReferenceSPI o1, ExternalReferenceSPI o2) {
    return (int) (o1.getResolutionCost() - o2.getResolutionCost());
  }
});

public static String getMimeType(ExternalReferenceSPI externalReference, InvocationContext context) {
  InputStream inputStream = externalReference.openStream(context);
  byte[] bytes = null;
  String mimeType = null;

  public int compare(ExternalReferenceSPI o1, ExternalReferenceSPI o2) {
    return (int) (o1.getResolutionCost() - o2.getResolutionCost());
  }
});

if (initialBuilder != null && sourceReference != null) {
  ExternalReferenceSPI builtReference = initialBuilder.createReference(
      sourceReference.openStream(context), context);
  results.add(builtReference);
  currentReference = builtReference;

  public int compare(ExternalReferenceSPI o1, ExternalReferenceSPI o2) {
    return (int) (o1.getResolutionCost() - o2.getResolutionCost());
  }
});