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javax.imageio.spi
abstract public class: ImageOutputStreamSpi [javadoc | source]
java.lang.Object
   javax.imageio.spi.IIOServiceProvider
      javax.imageio.spi.ImageOutputStreamSpi

All Implemented Interfaces:
    RegisterableService

The service provider interface (SPI) for ImageOutputStreams. For more information on service provider interfaces, see the class comment for the IIORegistry class.

This interface allows arbitrary objects to be "wrapped" by instances of ImageOutputStream. For example, a particular ImageOutputStreamSpi might allow a generic OutputStream to be used as a destination; another might output to a File or to a device such as a serial port.

By treating the creation of ImageOutputStreams as a pluggable service, it becomes possible to handle future output destinations without changing the API. Also, high-performance implementations of ImageOutputStream (for example, native implementations for a particular platform) can be installed and used transparently by applications.

Field Summary
protected  Class<?> outputClass    A Class object indicating the legal object type for use by the createInputStreamInstance method. 
Fields inherited from javax.imageio.spi.IIOServiceProvider:
vendorName,  version
Constructor:
 protected ImageOutputStreamSpi() 
 public ImageOutputStreamSpi(String vendorName,
    String version,
    Class<?> outputClass) 
    Constructs an ImageOutputStreamSpi with a given set of values.
    Parameters:
    vendorName - the vendor name.
    version - a version identifier.
    outputClass - a Class object indicating the legal object type for use by the createOutputStreamInstance method.
    Throws:
    IllegalArgumentException - if vendorName is null.
    IllegalArgumentException - if version is null.
    exception: IllegalArgumentException - if vendorName is null.
    exception: IllegalArgumentException - if version is null.
Method from javax.imageio.spi.ImageOutputStreamSpi Summary:
canUseCacheFile,   createOutputStreamInstance,   createOutputStreamInstance,   getOutputClass,   needsCacheFile
Methods from javax.imageio.spi.IIOServiceProvider:
getDescription,   getVendorName,   getVersion,   onDeregistration,   onRegistration
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from javax.imageio.spi.ImageOutputStreamSpi Detail:
 public boolean canUseCacheFile() 
    Returns true if the ImageOutputStream implementation associated with this service provider can optionally make use of a cache File for improved performance and/or memory footrprint. If false, the value of the cacheFile argument to createOutputStreamInstance will be ignored.

    The default implementation returns false.

 public ImageOutputStream createOutputStreamInstance(Object output) throws IOException 
    Returns an instance of the ImageOutputStream implementation associated with this service provider. A cache file will be created in the system-dependent default temporary-file directory, if needed.
 abstract public ImageOutputStream createOutputStreamInstance(Object output,
    boolean useCache,
    File cacheDir) throws IOException
    Returns an instance of the ImageOutputStream implementation associated with this service provider. If the use of a cache file is optional, the useCache parameter will be consulted. Where a cache is required, or not applicable, the value of useCache will be ignored.
 public Class<?> getOutputClass() 
    Returns a Class object representing the class or interface type that must be implemented by an output destination in order to be "wrapped" in an ImageOutputStream via the createOutputStreamInstance method.

    Typical return values might include OutputStream.class or File.class, but any class may be used.

 public boolean needsCacheFile() 
    Returns true if the ImageOutputStream implementation associated with this service provider requires the use of a cache File.

    The default implementation returns false.