ImageReaderSpi JDK 1.6)

Constructors

protected ImageReaderSpi ()

Constructs a blank ImageReaderSpi.

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

public ImageReaderSpi (String vendorName, String version, String names, String suffixes, String MIMETypes, String readerClassName, Class inputTypes, String writerSpiNames, boolean supportsStandardStreamMetadataFormat, String nativeStreamMetadataFormatName, String nativeStreamMetadataFormatClassName, String extraStreamMetadataFormatNames, String extraStreamMetadataFormatClassNames, boolean supportsStandardImageMetadataFormat, String nativeImageMetadataFormatName, String nativeImageMetadataFormatClassName, String extraImageMetadataFormatNames, String extraImageMetadataFormatClassNames)

Constructs an ImageReaderSpi with a given set of values.

Constructs an ImageReaderSpi with a given
set of values.
Parameters:
- vendorName - the vendor name, as a non-null String.
- version - a version identifier, as a non-null String.
- names - a non-null array of Strings indicating the format names. At least one entry must be present.
- suffixes - an array of Strings indicating the common file suffixes. If no suffixes are defined, null should be supplied. An array of length 0 will be normalized to null.
- MIMETypes - an array of Strings indicating the format's MIME types. If no MIME types are defined, null should be supplied. An array of length 0 will be normalized to null.
- readerClassName - the fully-qualified name of the associated ImageReader class, as a non-null String.
- inputTypes - a non-null array of Class objects of length at least 1 indicating the legal input types.
- writerSpiNames - an array Strings naming the classes of all associated ImageWriters, or null. An array of length 0 is normalized to null.
- supportsStandardStreamMetadataFormat - a boolean that indicates whether a stream metadata object can use trees described by the standard metadata format.
- nativeStreamMetadataFormatName - a String, or null, to be returned from getNativeStreamMetadataFormatName.
- nativeStreamMetadataFormatClassName - a String, or null, to be used to instantiate a metadata format object to be returned from getNativeStreamMetadataFormat.
- extraStreamMetadataFormatNames - an array of Strings, or null, to be returned from getExtraStreamMetadataFormatNames. An array of length 0 is normalized to null.
- extraStreamMetadataFormatClassNames - an array of Strings, or null, to be used to instantiate a metadata format object to be returned from getStreamMetadataFormat. An array of length 0 is normalized to null.
- supportsStandardImageMetadataFormat - a boolean that indicates whether an image metadata object can use trees described by the standard metadata format.
- nativeImageMetadataFormatName - a String, or null, to be returned from getNativeImageMetadataFormatName.
- nativeImageMetadataFormatClassName - a String, or null, to be used to instantiate a metadata format object to be returned from getNativeImageMetadataFormat.
- extraImageMetadataFormatNames - an array of Strings to be returned from getExtraImageMetadataFormatNames. An array of length 0 is normalized to null.
- extraImageMetadataFormatClassNames - an array of Strings, or null, to be used to instantiate a metadata format object to be returned from getImageMetadataFormat. An array of length 0 is normalized to null.
Throws:
- IllegalArgumentException - if vendorName is null.
- IllegalArgumentException - if version is null.
- IllegalArgumentException - if names is null or has length 0.
- IllegalArgumentException - if readerClassName is null.
- IllegalArgumentException - if inputTypes is null or has length 0.

Methods

Hide/Show inherited methods

publicabstract boolean canDecodeInput (Object source) throws IOException

Returns true if the supplied source object appears to be of the format supported by this reader.

Returns true if the supplied source object appears to be of the format supported by this reader. Returning true from this method does not guarantee that reading will succeed, only that there appears to be a reasonable chance of success based on a brief inspection of the stream contents. If the source is an ImageInputStream, implementations will commonly check the first several bytes of the stream for a "magic number" associated with the format. Once actual reading has commenced, the reader may still indicate failure at any time prior to the completion of decoding.

It is important that the state of the object not be disturbed in order that other ImageReaderSpis can properly determine whether they are able to decode the object. In particular, if the source is an ImageInputStream, a mark/reset pair should be used to preserve the stream position.

Formats such as "raw," which can potentially attempt to read nearly any stream, should return false in order to avoid being invoked in preference to a closer match.

If source is not an instance of one of the classes returned by getInputTypes, the method should simply return false.
Returns: true if it is likely that this stream can be decoded.
Parameters:
- source - the object (typically an ImageInputStream) to be decoded.
Throws:
- IllegalArgumentException - if source is null.
- IOException - if an I/O error occurs while reading the stream.

public ImageReader createReaderInstance () throws IOException

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

Returns an instance of the ImageReader implementation associated with this service provider. The returned object will initially be in an initial state as if its reset method had been called.

The default implementation simply returns createReaderInstance(null).
Returns: an ImageReader instance.
Throws:
- IOException - if an error occurs during loading, or initialization of the reader class, or during instantiation or initialization of the reader object.

publicabstract ImageReader createReaderInstance (Object extension) throws IOException

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

Returns an instance of the ImageReader implementation associated with this service provider. The returned object will initially be in an initial state as if its reset method had been called.

An Object may be supplied to the plug-in at construction time. The nature of the object is entirely plug-in specific.

Typically, a plug-in will implement this method using code such as return new MyImageReader(this).
Returns: an ImageReader instance.
Parameters:
- extension - a plug-in specific extension object, which may be null.
Throws:
- IOException - if the attempt to instantiate the reader fails.
- IllegalArgumentException - if the ImageReader's contructor throws an IllegalArgumentException to indicate that the extension object is unsuitable.

publicabstract String getDescription (Locale locale) [Inherited From IIOServiceProvider]

Returns a brief, human-readable description of this service provider and its associated implementation.

Returns a brief, human-readable description of this service
provider and its associated implementation. The resulting
string should be localized for the supplied
Locale, if possible.
Returns: a String containing a description of this service provider.
Parameters:
- locale - a Locale for which the return value should be localized.

public String getExtraImageMetadataFormatNames () [Inherited From ImageReaderWriterSpi]

Returns an array of Strings containing the names of additional document formats, other than the native and standard formats, recognized by the getAsTree and setFromTree methods on the image metadata objects produced or consumed by this plug-in.

If the plug-in does not handle image metadata, null should be returned.

The set of formats may differ according to the particular images being read or written; this method should indicate all the additional formats supported by the plug-in under any circumstances.

The default implementation returns a clone of the extraImageMetadataFormatNames instance variable, which is typically set by the constructor.
Returns: an array of Strings, or null.
See Also: IIOMetadata.getMetadataFormatNames(), ImageReaderWriterSpi.getExtraStreamMetadataFormatNames(), ImageReaderWriterSpi.getNativeImageMetadataFormatName(),

public String getExtraStreamMetadataFormatNames () [Inherited From ImageReaderWriterSpi]

Returns an array of Strings containing the names of additional document formats, other than the native and standard formats, recognized by the getAsTree and setFromTree methods on the stream metadata objects produced or consumed by this plug-in.

If the plug-in does not handle metadata, null should be returned.

The set of formats may differ according to the particular images being read or written; this method should indicate all the additional formats supported by the plug-in under any circumstances.

The default implementation returns a clone of the extraStreamMetadataFormatNames instance variable, which is typically set by the constructor.
Returns: an array of Strings, or null.
See Also: IIOMetadata.getMetadataFormatNames(), ImageReaderWriterSpi.getExtraImageMetadataFormatNames(), ImageReaderWriterSpi.getNativeStreamMetadataFormatName(),

public String getFileSuffixes () [Inherited From ImageReaderWriterSpi]

Returns an array of Strings containing a list of file suffixes associated with the formats that are generally usable by the ImageReader or ImageWriter implementation associated with this service provider. For example, a single ImageReader might be able to process files with '.pbm' and '.pnm' suffixes, or both '.jpg' and '.jpeg' suffixes. If there are no known file suffixes, null will be returned.

Returning a particular suffix does not guarantee that files with that suffix can be processed; it merely indicates that it may be worthwhile attempting to decode or encode such files using this service provider.
Returns: an array of Strings or length at least 1 containing common file suffixes associated with this reader or writer, or null.

public String getFormatNames () [Inherited From ImageReaderWriterSpi]

Returns an array of Strings containing human-readable names for the formats that are generally usable by the ImageReader or ImageWriter implementation associated with this service provider.

Returns an array of Strings containing
human-readable names for the formats that are generally usable
by the ImageReader or ImageWriter
implementation associated with this service provider. For
example, a single ImageReader might be able to
process both PBM and PNM files.
Returns: a non-null array of Strings or length at least 1 containing informal format names associated with this reader or writer.

public IIOMetadataFormat getImageMetadataFormat (String formatName) [Inherited From ImageReaderWriterSpi]

Returns an IIOMetadataFormat object describing the given image metadata format, or null if no description is available.

Returns an IIOMetadataFormat object describing the
given image metadata format, or null if no
description is available. The supplied name must be the native
iamge metadata format name, the standard metadata format name,
or one of those returned by
getExtraImageMetadataFormatNames.
Returns: an IIOMetadataFormat object.
Parameters:
- formatName - the desired image metadata format.
Throws:
- IllegalArgumentException - if formatName is null or is not a supported name.

public String getImageWriterSpiNames ()

Returns an array of Strings containing the fully qualified names of all the ImageWriterSpi classes that can understand the internal metadata representation used by the ImageReader associated with this service provider, or null if there are no such ImageWriters specified.

The first item in the array must be the name of the service provider for the "preferred" writer, as it will be used to instantiate the ImageWriter returned by ImageIO.getImageWriter(ImageReader).

This mechanism may be used to obtain ImageWriters that will understand the internal structure of non-pixel meta-data (see IIOTreeInfo) generated by an ImageReader. By obtaining this data from the ImageReader and passing it on to one of the ImageWriters obtained with this method, a client program can read an image, modify it in some way, and write it back out while preserving all meta-data, without having to understand anything about the internal structure of the meta-data, or even about the image format.
Returns: an array of Strings of length at least 1 containing names of ImageWriterSpi, or null.
See Also: ImageIO.getImageWriter(ImageReader),

public Class getInputTypes ()

Returns an array of Class objects indicating what types of objects may be used as arguments to the reader's setInput method.

For most readers, which only accept input from an ImageInputStream, a single-element array containing ImageInputStream.class should be returned.
Returns: a non-null array of Classobjects of length at least 1.

public String getMIMETypes () [Inherited From ImageReaderWriterSpi]

Returns an array of Strings containing a list of MIME types associated with the formats that are generally usable by the ImageReader or ImageWriter implementation associated with this service provider.

Ideally, only a single MIME type would be required in order to describe a particular format. However, for several reasons it is necessary to associate a list of types with each service provider. First, many common image file formats do not have standard MIME types, so a list of commonly used unofficial names will be required, such as image/x-pbm and image/x-portable-bitmap. Some file formats have official MIME types but may sometimes be referred to using their previous unofficial designations, such as image/x-png instead of the official image/png. Finally, a single service provider may be capable of parsing multiple distinct types from the MIME point of view, for example image/x-xbitmap and image/x-xpixmap.

Returning a particular MIME type does not guarantee that files claiming to be of that type can be processed; it merely indicates that it may be worthwhile attempting to decode or encode such files using this service provider.
Returns: an array of Strings or length at least 1 containing MIME types associated with this reader or writer, or null.

public String getNativeImageMetadataFormatName () [Inherited From ImageReaderWriterSpi]

Returns the name of the "native" image metadata format for this plug-in, which typically allows for lossless encoding and transmission of the image metadata stored in the format handled by this plug-in.

The default implementation returns the nativeImageMetadataFormatName instance variable, which is typically set by the constructor.
Returns: the name of the native image metadata format, or null.
See Also: ImageReaderWriterSpi.getExtraImageMetadataFormatNames(),

public String getNativeStreamMetadataFormatName () [Inherited From ImageReaderWriterSpi]

Returns the name of the "native" stream metadata format for this plug-in, which typically allows for lossless encoding and transmission of the stream metadata stored in the format handled by this plug-in.

The default implementation returns the nativeStreamMetadataFormatName instance variable, which is typically set by the constructor.
Returns: the name of the native stream metadata format, or null.

public String getPluginClassName () [Inherited From ImageReaderWriterSpi]

Returns the fully-qualified class name of the ImageReader or ImageWriter plug-in associated with this service provider.

Returns the fully-qualified class name of the
ImageReader or ImageWriter plug-in
associated with this service provider.
Returns: the class name, as a non-null String.

public IIOMetadataFormat getStreamMetadataFormat (String formatName) [Inherited From ImageReaderWriterSpi]

Returns an IIOMetadataFormat object describing the given stream metadata format, or null if no description is available.

Returns an IIOMetadataFormat object describing the
given stream metadata format, or null if no
description is available. The supplied name must be the native
stream metadata format name, the standard metadata format name,
or one of those returned by
getExtraStreamMetadataFormatNames.
Returns: an IIOMetadataFormat object.
Parameters:
- formatName - the desired stream metadata format.
Throws:
- IllegalArgumentException - if formatName is null or is not a supported name.

public String getVendorName () [Inherited From IIOServiceProvider]

Returns the name of the vendor responsible for creating this service provider and its associated implementation.

public String getVersion () [Inherited From IIOServiceProvider]

Returns a string describing the version number of this service provider and its associated implementation.

public boolean isOwnReader (ImageReader reader)

Returns true if the ImageReader object passed in is an instance of the ImageReader associated with this service provider.

The default implementation compares the fully-qualified class name of the reader argument with the class name passed into the constructor. This method may be overridden if more sophisticated checking is required.
Returns: true if reader is recognized.
Parameters:
- reader - an ImageReader instance.
Throws:
- IllegalArgumentException - if reader is null.

public boolean isStandardImageMetadataFormatSupported () [Inherited From ImageReaderWriterSpi]

Returns true if the standard metadata format is among the document formats recognized by the getAsTree and setFromTree methods on the image metadata objects produced or consumed by this plug-in.

Returns true if the standard metadata format is
among the document formats recognized by the
getAsTree and setFromTree methods on
the image metadata objects produced or consumed by this
plug-in.
Returns: true if the standard format is supported for image metadata.

public boolean isStandardStreamMetadataFormatSupported () [Inherited From ImageReaderWriterSpi]

Returns true if the standard metadata format is among the document formats recognized by the getAsTree and setFromTree methods on the stream metadata objects produced or consumed by this plug-in.

Returns true if the standard metadata format is
among the document formats recognized by the
getAsTree and setFromTree methods on
the stream metadata objects produced or consumed by this
plug-in.
Returns: true if the standard format is supported for stream metadata.

public void onDeregistration (ServiceRegistry registry, Class<Object> category) [Inherited From IIOServiceProvider]

A callback that will be whenever the Spi class has been deregistered from a ServiceRegistry.

Only the registry should call this method.

The default implementation does nothing.
See Also: ServiceRegistry.deregisterServiceProvider(Object provider),

public void onRegistration (ServiceRegistry registry, Class<Object> category) [Inherited From IIOServiceProvider]

A callback that will be called exactly once after the Spi class has been instantiated and registered in a ServiceRegistry.

A callback that will be called exactly once after the Spi class has been instantiated and registered in a ServiceRegistry. This may be used to verify that the environment is suitable for this service, for example that native libraries can be loaded. If the service cannot function in the environment where it finds itself, it should deregister itself from the registry.

Only the registry should call this method.

The default implementation does nothing.
See Also: ServiceRegistry.registerServiceProvider(Object provider),

Fields

Hide/Show inherited fields

protected String extraImageMetadataFormatClassNames [Inherited From ImageReaderWriterSpi]

An array of Strings containing the class names of any additional image metadata formats supported by this plug-in, initially null.

protected String extraImageMetadataFormatNames [Inherited From ImageReaderWriterSpi]

An array of Strings containing the names of any additional image metadata formats supported by this plug-in, initially null.

protected String extraStreamMetadataFormatClassNames [Inherited From ImageReaderWriterSpi]

An array of Strings containing the class names of any additional stream metadata formats supported by this plug-in, initially null.

protected String extraStreamMetadataFormatNames [Inherited From ImageReaderWriterSpi]

An array of Strings containing the names of any additional stream metadata formats supported by this plug-in, initially null.

protected Class inputTypes

An array of Class objects to be returned from getInputTypes, initially null.

protected String MIMETypes [Inherited From ImageReaderWriterSpi]

An array of strings to be returned from getMIMETypes, initially null.

protected String names [Inherited From ImageReaderWriterSpi]

An array of strings to be returned from getFormatNames, initially null.

An array of strings to be returned from
getFormatNames, initially null.
Constructors should set this to a non-null value.

protected String nativeImageMetadataFormatClassName [Inherited From ImageReaderWriterSpi]

A String containing the class name of the native stream metadata format supported by this plug-in, initially null.

protected String nativeImageMetadataFormatName [Inherited From ImageReaderWriterSpi]

A String containing the name of the native stream metadata format supported by this plug-in, initially null.

protected String nativeStreamMetadataFormatClassName [Inherited From ImageReaderWriterSpi]

A String containing the class name of the native stream metadata format supported by this plug-in, initially null.

protected String nativeStreamMetadataFormatName [Inherited From ImageReaderWriterSpi]

A String containing the name of the native stream metadata format supported by this plug-in, initially null.

protected String pluginClassName [Inherited From ImageReaderWriterSpi]

A String containing the name of the associated plug-in class, initially null.

publicfinalstatic Class STANDARD_INPUT_TYPE

A single-element array, initially containing ImageInputStream.class, to be returned from getInputTypes.

protected String suffixes [Inherited From ImageReaderWriterSpi]

An array of strings to be returned from getFileSuffixes, initially null.

protected boolean supportsStandardImageMetadataFormat [Inherited From ImageReaderWriterSpi]

A boolean indicating whether this plug-in supports the standard metadata format for image metadata, initially false.

protected boolean supportsStandardStreamMetadataFormat [Inherited From ImageReaderWriterSpi]

A boolean indicating whether this plug-in supports the standard metadata format for stream metadata, initially false.

protected String vendorName [Inherited From IIOServiceProvider]

A String to be returned from getVendorName, initially null.

A String to be returned from
getVendorName, initially null.
Constructors should set this to a non-null value.

protected String version [Inherited From IIOServiceProvider]

A String to be returned from getVersion, initially null.

A String to be returned from
getVersion, initially null. Constructors should
set this to a non-null value.

protected String writerSpiNames

An array of strings to be returned from getImageWriterSpiNames, initially null.