it.geosolutions.imageio.stream.input.spi

Class FileImageInputStreamExtImplSpi

java.lang.Object

javax.imageio.spi.IIOServiceProvider

javax.imageio.spi.ImageInputStreamSpi

it.geosolutions.imageio.stream.input.spi.FileImageInputStreamExtImplSpi

All Implemented Interfaces:

RegisterableService

public class FileImageInputStreamExtImplSpi
extends ImageInputStreamSpi

Implementation of an ImageInputStreamSpi for instantiating an ImageInputStream capable of connecting to a File by means of an EnhancedRandomAccessFile which gives buffering capabilities.

It is worth to point out that ImageIO already provide the FileChannelImageInputStream in order to efficiently access images with buffering. despite to this I have ran into many problems with FileChannels especially on Windows machines, hence I came up with this ImageInputStream subclass and this ImageInputStreamSpi which gives similar performances for most uses but far less problems.

Author:

Daniele Romagnoli, GeoSolutions, Simone Giannecchini, GeoSolutions

See Also:

ImageInputStream, ImageInputStreamSpi, ImageIO.createImageInputStream(Object)

Constructor Summary

Constructors

Constructor and Description
FileImageInputStreamExtImplSpi() Constructs a blank ImageInputStreamSpi.

Method Summary

Modifier and Type	Method and Description
ImageInputStream	createInputStreamInstance(Object input, boolean useCache, File cacheDir) Returns an instance of the ImageInputStream implementation associated with this service provider.
String	getDescription(Locale locale)
static boolean	isUseFileChannel()
void	onRegistration(ServiceRegistry registry, Class<?> category) Upon registration, this method ensures that this SPI is listed at the top of the ImageInputStreamSpi items, so that it will be invoked before the default FileImageInputStreamSpi
static void	setUseFileChannel(boolean useFileChannel)

Methods inherited from class javax.imageio.spi.ImageInputStreamSpi

canUseCacheFile, createInputStreamInstance, getInputClass, needsCacheFile

Methods inherited from class javax.imageio.spi.IIOServiceProvider

getVendorName, getVersion, onDeregistration

Methods inherited from class java.lang.Object

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

Constructor Detail

FileImageInputStreamExtImplSpi

public FileImageInputStreamExtImplSpi()

Constructs a blank ImageInputStreamSpi. It is up to the subclass to initialize instance variables and/or override method implementations in order to provide working versions of all methods.

Method Detail

getDescription

public String getDescription(Locale locale)

Specified by:

getDescription in class IIOServiceProvider

See Also:

IIOServiceProvider.getDescription(Locale).

onRegistration

public void onRegistration(ServiceRegistry registry,
                           Class<?> category)

Upon registration, this method ensures that this SPI is listed at the top of the ImageInputStreamSpi items, so that it will be invoked before the default FileImageInputStreamSpi

Specified by:

onRegistration in interface RegisterableService

Overrides:

onRegistration in class IIOServiceProvider

Parameters:

registry - ServiceRegistry where this object has been registered.

category - a Class object indicating the registry category under which this object has been registered.

createInputStreamInstance

public ImageInputStream createInputStreamInstance(Object input,
                                                  boolean useCache,
                                                  File cacheDir)

Returns an instance of the ImageInputStream implementation associated with this service provider.

Specified by:

createInputStreamInstance in class ImageInputStreamSpi

Parameters:

input - an object of the class type returned by getInputClass.

useCache - a boolean indicating whether a cache eraf should be used, in cases where it is optional.

cacheDir - a File indicating where the cache eraf should be created, or null to use the system directory.

Returns:

an ImageInputStream instance.

Throws:

IllegalArgumentException - if input is not an instance of the correct class or is null.

isUseFileChannel

public static boolean isUseFileChannel()

setUseFileChannel

public static void setUseFileChannel(boolean useFileChannel)