Package Summary Overview Summary

### class:ImageOutputStreamSpi [NONE]
- All Implemented Interfaces: RegisterableService
      public abstract class ImageOutputStreamSpi
      extends IIOServiceProvider
The service provider interface (SPI) for `ImageOutputStream`s. 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 `ImageOutputStream`s 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. See Also: `IIORegistry`, `ImageOutputStream`

### field:outputClass [NONE]
- #### outputClass
      protected Class<?> outputClass
A `Class` object indicating the legal object type for use by the `createInputStreamInstance` method.

### constructor:ImageOutputStreamSpi() [NONE]
- #### ImageOutputStreamSpi
      protected ImageOutputStreamSpi()
Constructs a blank `ImageOutputStreamSpi`. It is up to the subclass to initialize instance variables and/or override method implementations in order to provide working versions of all methods.

### constructor:ImageOutputStreamSpi(java.lang.String, java.lang.String, java.lang.Class) [NONE]
- #### 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`.

### method:getOutputClass() [NONE]
- #### getOutputClass
      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. Returns: a `Class` variable. See Also: `createOutputStreamInstance(Object, boolean, File)`

### method:canUseCacheFile() [NONE]
- #### canUseCacheFile
      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`. Returns: `true` if a cache file can be used by the output streams created by this service provider.

### method:needsCacheFile() [NONE]
- #### needsCacheFile
      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`. Returns: `true` if a cache file is needed by the output streams created by this service provider.

### method:createOutputStreamInstance(java.lang.Object, boolean, java.io.File) [NONE]
- #### createOutputStreamInstance
      public abstract 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. Parameters: `output` - an object of the class type returned by `getOutputClass`. `useCache` - a `boolean` indicating whether a cache file should be used, in cases where it is optional. `cacheDir` - a `File` indicating where the cache file should be created, or `null` to use the system directory. Returns: an `ImageOutputStream` instance. Throws: `IllegalArgumentException` - if `output` is not an instance of the correct class or is `null`. `IllegalArgumentException` - if a cache file is needed, but `cacheDir` is non-`null` and is not a directory. `IOException` - if a cache file is needed but cannot be created. See Also: `getOutputClass()`

### method:createOutputStreamInstance(java.lang.Object) [NONE]
- #### createOutputStreamInstance
      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. Parameters: `output` - an object of the class type returned by `getOutputClass`. Returns: an `ImageOutputStream` instance. Throws: `IllegalArgumentException` - if `output` is not an instance of the correct class or is `null`. `IOException` - if a cache file is needed but cannot be created. See Also: `getOutputClass()`