public abstract class ImageWriterSpi extends ImageReaderWriterSpi
ImageWriters.
 For more information on service provider classes, see the class comment
 for the IIORegistry class.
  Each ImageWriterSpi provides several types of information
 about the ImageWriter class with which it is associated.
 
 The name of the vendor who defined the SPI class and a
 brief description of the class are available via the
 getVendorName, getDescription,
 and getVersion methods.
 These methods may be internationalized to provide locale-specific
 output.  These methods are intended mainly to provide short,
 human-writable information that might be used to organize a pop-up
 menu or other list.
 
 Lists of format names, file suffixes, and MIME types associated
 with the service may be obtained by means of the
 getFormatNames, getFileSuffixes, and
 getMIMEType methods.  These methods may be used to
 identify candidate ImageWriters for writing a
 particular file or stream based on manual format selection, file
 naming, or MIME associations.
 
 A more reliable way to determine which ImageWriters
 are likely to be able to parse a particular data stream is provided
 by the canEncodeImage method.  This methods allows the
 service provider to inspect the actual image contents.
 
 Finally, an instance of the ImageWriter class
 associated with this service provider may be obtained by calling
 the createWriterInstance method.  Any heavyweight
 initialization, such as the loading of native libraries or creation
 of large tables, should be deferred at least until the first
 invocation of this method.
IIORegistry, 
ImageTypeSpecifier, 
ImageWriter| Modifier and Type | Field and Description | 
|---|---|
| protected Class[] | outputTypesAn array of  Classobjects to be returned fromgetOutputTypes, initiallynull. | 
| protected String[] | readerSpiNamesAn array of strings to be returned from
  getImageReaderSpiNames, initiallynull. | 
| static Class[] | STANDARD_OUTPUT_TYPEDeprecated. 
 Instead of using this field, directly create
 the equivalent array  { ImageOutputStream.class }. | 
extraImageMetadataFormatClassNames, extraImageMetadataFormatNames, extraStreamMetadataFormatClassNames, extraStreamMetadataFormatNames, MIMETypes, names, nativeImageMetadataFormatClassName, nativeImageMetadataFormatName, nativeStreamMetadataFormatClassName, nativeStreamMetadataFormatName, pluginClassName, suffixes, supportsStandardImageMetadataFormat, supportsStandardStreamMetadataFormatvendorName, version| Modifier | Constructor and Description | 
|---|---|
| protected  | ImageWriterSpi()Constructs a blank  ImageWriterSpi. | 
|   | ImageWriterSpi(String vendorName,
              String version,
              String[] names,
              String[] suffixes,
              String[] MIMETypes,
              String writerClassName,
              Class[] outputTypes,
              String[] readerSpiNames,
              boolean supportsStandardStreamMetadataFormat,
              String nativeStreamMetadataFormatName,
              String nativeStreamMetadataFormatClassName,
              String[] extraStreamMetadataFormatNames,
              String[] extraStreamMetadataFormatClassNames,
              boolean supportsStandardImageMetadataFormat,
              String nativeImageMetadataFormatName,
              String nativeImageMetadataFormatClassName,
              String[] extraImageMetadataFormatNames,
              String[] extraImageMetadataFormatClassNames)Constructs an  ImageWriterSpiwith a given
 set of values. | 
| Modifier and Type | Method and Description | 
|---|---|
| abstract boolean | canEncodeImage(ImageTypeSpecifier type)Returns  trueif theImageWriterimplementation associated with this service provider is able to
 encode an image with the given layout. | 
| boolean | canEncodeImage(RenderedImage im)Returns  trueif theImageWriterimplementation associated with this service provider is able to
 encode the givenRenderedImageinstance. | 
| ImageWriter | createWriterInstance()Returns an instance of the  ImageWriterimplementation associated with this service provider. | 
| abstract ImageWriter | createWriterInstance(Object extension)Returns an instance of the  ImageWriterimplementation associated with this service provider. | 
| String[] | getImageReaderSpiNames()Returns an array of  Strings containing all the
 fully qualified names of all theImageReaderSpiclasses that can understand the internal metadata
 representation used by theImageWriterassociated
 with this service provider, ornullif there are
 no suchImageReadersspecified. | 
| Class[] | getOutputTypes()Returns an array of  Classobjects indicating what
 types of objects may be used as arguments to the writer'ssetOutputmethod. | 
| boolean | isFormatLossless()Returns  trueif the format that this writer
 outputs preserves pixel data bit-accurately. | 
| boolean | isOwnWriter(ImageWriter writer)Returns  trueif theImageWriterobject
 passed in is an instance of theImageWriterassociated with this service provider. | 
getExtraImageMetadataFormatNames, getExtraStreamMetadataFormatNames, getFileSuffixes, getFormatNames, getImageMetadataFormat, getMIMETypes, getNativeImageMetadataFormatName, getNativeStreamMetadataFormatName, getPluginClassName, getStreamMetadataFormat, isStandardImageMetadataFormatSupported, isStandardStreamMetadataFormatSupportedgetDescription, getVendorName, getVersion, onDeregistration, onRegistration@Deprecated public static final Class[] STANDARD_OUTPUT_TYPE
{ ImageOutputStream.class }.ImageOutputStream.class, to be returned from
 getOutputTypes.protected Class[] outputTypes
Class objects to be returned from
 getOutputTypes, initially null.protected String[] readerSpiNames
getImageReaderSpiNames, initially
 null.protected ImageWriterSpi()
ImageWriterSpi.  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 ImageWriterSpi(String vendorName, String version, String[] names, String[] suffixes, String[] MIMETypes, String writerClassName, Class[] outputTypes, String[] readerSpiNames, boolean supportsStandardStreamMetadataFormat, String nativeStreamMetadataFormatName, String nativeStreamMetadataFormatClassName, String[] extraStreamMetadataFormatNames, String[] extraStreamMetadataFormatClassNames, boolean supportsStandardImageMetadataFormat, String nativeImageMetadataFormatName, String nativeImageMetadataFormatClassName, String[] extraImageMetadataFormatNames, String[] extraImageMetadataFormatClassNames)
ImageWriterSpi with a given
 set of values.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 suffixes are defined,
 null should be supplied.  An array of length 0
 will be normalized to null.writerClassName - the fully-qualified name of the
 associated ImageWriterSpi class, as a
 non-null String.outputTypes - an array of Class objects of
 length at least 1 indicating the legal output types.readerSpiNames - an array Strings of length
 at least 1 naming the classes of all associated
 ImageReaders, 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.IllegalArgumentException - if vendorName
 is null.IllegalArgumentException - if version
 is null.IllegalArgumentException - if names
 is null or has length 0.IllegalArgumentException - if writerClassName
 is null.IllegalArgumentException - if outputTypes
 is null or has length 0.public boolean isFormatLossless()
true if the format that this writer
 outputs preserves pixel data bit-accurately.  The default
 implementation returns true.true if the format preserves full pixel
 accuracy.public Class[] getOutputTypes()
Class objects indicating what
 types of objects may be used as arguments to the writer's
 setOutput method.
  For most writers, which only output to an
 ImageOutputStream, a single-element array
 containing ImageOutputStream.class should be
 returned.
null array of
 Classobjects of length at least 1.public abstract boolean canEncodeImage(ImageTypeSpecifier type)
true if the ImageWriter
 implementation associated with this service provider is able to
 encode an image with the given layout.  The layout
 (i.e., the image's SampleModel and
 ColorModel) is described by an
 ImageTypeSpecifier object.
  A return value of true is not an absolute
 guarantee of successful encoding; the encoding process may still
 produce errors due to factors such as I/O errors, inconsistent
 or malformed data structures, etc.  The intent is that a
 reasonable inspection of the basic structure of the image be
 performed in order to determine if it is within the scope of
 the encoding format.  For example, a service provider for a
 format that can only encode greyscale would return
 false if handed an RGB BufferedImage.
 Similarly, a service provider for a format that can encode
 8-bit RGB imagery might refuse to encode an image with an
 associated alpha channel.
 
 Different ImageWriters, and thus service
 providers, may choose to be more or less strict.  For example,
 they might accept an image with premultiplied alpha even though
 it will have to be divided out of each pixel, at some loss of
 precision, in order to be stored.
type - an ImageTypeSpecifier specifying the
 layout of the image to be written.true if this writer is likely to be able
 to encode images with the given layout.IllegalArgumentException - if type
 is null.public boolean canEncodeImage(RenderedImage im)
true if the ImageWriter
 implementation associated with this service provider is able to
 encode the given RenderedImage instance.  Note
 that this includes instances of
 java.awt.image.BufferedImage.
  See the discussion for
 canEncodeImage(ImageTypeSpecifier) for information
 on the semantics of this method.
im - an instance of RenderedImage to be encoded.true if this writer is likely to be able
 to encode this image.IllegalArgumentException - if im
 is null.public ImageWriter createWriterInstance() throws IOException
ImageWriter
 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
 createWriterInstance(null).
ImageWriter instance.IOException - if an error occurs during loading,
 or initialization of the writer class, or during instantiation
 or initialization of the writer object.public abstract ImageWriter createWriterInstance(Object extension) throws IOException
ImageWriter
 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 MyImageWriter(this).
extension - a plug-in specific extension object, which may
 be null.ImageWriter instance.IOException - if the attempt to instantiate
 the writer fails.IllegalArgumentException - if the
 ImageWriter's constructor throws an
 IllegalArgumentException to indicate that the
 extension object is unsuitable.public boolean isOwnWriter(ImageWriter writer)
true if the ImageWriter object
 passed in is an instance of the ImageWriter
 associated with this service provider.writer - an ImageWriter instance.true if writer is recognizedIllegalArgumentException - if writer is
 null.public String[] getImageReaderSpiNames()
Strings containing all the
 fully qualified names of all the ImageReaderSpi
 classes that can understand the internal metadata
 representation used by the ImageWriter associated
 with this service provider, or null if there are
 no such ImageReaders specified.  If a
 non-null value is returned, it must have non-zero
 length.
  The first item in the array must be the name of the service
 provider for the "preferred" reader, as it will be used to
 instantiate the ImageReader returned by
 ImageIO.getImageReader(ImageWriter).
 
 This mechanism may be used to obtain
 ImageReaders that will generated non-pixel
 meta-data (see IIOExtraDataInfo) in a structure
 understood by an ImageWriter.  By reading the
 image and obtaining this data from one of the
 ImageReaders obtained with this method and passing
 it on to the ImageWriter, a client program can
 read an image, modify it in some way, and write it back out
 preserving all meta-data, without having to understand anything
 about the internal structure of the meta-data, or even about
 the image format.
Strings of length at least 1
 containing names of ImageReaderSpis, or
 null.ImageIO.getImageReader(ImageWriter), 
ImageReaderSpi.getImageWriterSpiNames() Submit a bug or feature 
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