Package org.dspace.app.iiif.service

Class CanvasService

java.lang.Object

org.dspace.app.iiif.service.AbstractResourceService

org.dspace.app.iiif.service.CanvasService

@RequestScope
@Component
public class CanvasService
extends AbstractResourceService

This service provides methods for creating Canvases. There should be a single instance of this service per request. The @RequestScope provides a single instance created and available during complete lifecycle of the HTTP request.

Author:

Michael Spalti mspalti@willamette.edu, Andrea Bollini (andrea.bollini at 4science.it)

Field Summary

Fields

Modifier and Type	Field	Description
protected String[]	BITSTREAM_METADATA_FIELDS

Fields inherited from class org.dspace.app.iiif.service.AbstractResourceService

BITSTREAM_PATH_PREFIX, CLIENT_URL, DEFAULT_CANVAS_HEIGHT, DEFAULT_CANVAS_WIDTH, defaultCanvasHeightFallback, defaultCanvasWidthFallback, DOCUMENT_VIEWING_HINT, IIIF_ENDPOINT, IIIF_LOGO_IMAGE, IMAGE_PATH, IMAGE_SERVICE, SEARCH_URL, THUMBNAIL_PATH

Constructor Summary

Constructors

Constructor	Description
CanvasService(org.dspace.services.ConfigurationService configurationService)	Constructor.

Method Summary

Modifier and Type	Method	Description
protected CanvasGenerator	getCanvas(Context context, String manifestId, Bitstream bitstream, Bundle bundle, Item item, int count, String mimeType)	Creates a single CanvasGenerator.
protected CanvasGenerator	getRangeCanvasReference(String startCanvas)	Ranges expect the Canvas object to have only an identifier.
protected void	guessCanvasDimensions(Context context, List<Bundle> bundles)	Checks for "iiif.image.width" metadata in IIIF bundles.

Methods inherited from class org.dspace.app.iiif.service.AbstractResourceService

getManifestId, setConfiguration, setDefaultCanvasDimensions

Methods inherited from class java.lang.Object

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

Field Details

BITSTREAM_METADATA_FIELDS

protected String[] BITSTREAM_METADATA_FIELDS

Constructor Details

CanvasService

public CanvasService(org.dspace.services.ConfigurationService configurationService)

Constructor.

Parameters:

configurationService - the DSpace configuration service.

Method Details

guessCanvasDimensions

protected void guessCanvasDimensions(Context context,
 List<Bundle> bundles)

Checks for "iiif.image.width" metadata in IIIF bundles. When bitstream metadata is not found for the first image in the bundle this method updates the default canvas dimensions for the request based on the actual image dimensions, using the IIIF image service. Called once for each manifest.

Parameters:

bundles - IIIF bundles for this item

getCanvas

protected CanvasGenerator getCanvas(Context context,
 String manifestId,
 Bitstream bitstream,
 Bundle bundle,
 Item item,
 int count,
 String mimeType)

Creates a single CanvasGenerator.

Parameters:

context - DSpace Context

manifestId - manifest id

bitstream - DSpace bitstream

bundle - DSpace bundle

item - DSpace item

count - the canvas position in the sequence.

mimeType - bitstream mimetype

Returns:

a canvas generator

getRangeCanvasReference

protected CanvasGenerator getRangeCanvasReference(String startCanvas)

Ranges expect the Canvas object to have only an identifier.

Parameters:

startCanvas - the start canvas identifier

Returns:

canvas generator