Package engineering.everest.starterkit.media.thumbnails

Class ThumbnailService

java.lang.Object

engineering.everest.starterkit.media.thumbnails.ThumbnailService

@Component
public class ThumbnailService
extends Object

Service layer for thumbnails.

The maximum size of either height or width of a generated thumbnail can be configured using the application.media.thumbnail.max.dimension.pixels property.

Constructor Summary

Constructors

Constructor	Description
ThumbnailService(int maxDimensionPixels, engineering.everest.starterkit.filestorage.FileService fileService, ThumbnailMappingRepository thumbnailMappingRepository)

Method Summary

Modifier and Type	Method	Description
void	deleteAllThumbnailMappings()	Clear all thumbnail mappings.
Set<UUID>	getAllThumbnailFileIds()
InputStream	streamThumbnailForOriginalFile(UUID fileId, int width, int height)	Generates a thumbnail for a file stored by one of the deduplicating filestores.

Methods inherited from class java.lang.Object

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

Constructor Details

ThumbnailService

@Autowired
public ThumbnailService(@Value("${application.media.thumbnail.max.dimension.pixels:2400}")
 int maxDimensionPixels,
 engineering.everest.starterkit.filestorage.FileService fileService,
 ThumbnailMappingRepository thumbnailMappingRepository)

Method Details

streamThumbnailForOriginalFile

public InputStream streamThumbnailForOriginalFile(UUID fileId,
 int width,
 int height)
                                           throws IOException

Generates a thumbnail for a file stored by one of the deduplicating filestores.

Generated thumbnails are cached on the ephemeral file store. Callers are responsible for closing the returned input stream.

Parameters:

fileId - UUID returned by the PermanentDeduplicatingFileStore or the EphemeralDefuplicatingFileStore

width - desired thumbnail width

height - desried thumbnail height

Returns:

an input stream to retrieve a thumbnail.

Throws:

IOException - if the original file cannot be read

IllegalArgumentException - if the thumbnail dimensions are impossibly small or larger than the maximum supported.

getAllThumbnailFileIds

public Set<UUID> getAllThumbnailFileIds()

deleteAllThumbnailMappings

public void deleteAllThumbnailMappings()

Clear all thumbnail mappings.