Module java.desktop

Class IIORegistry

public final class IIORegistry extends ServiceRegistry
A registry for Image I/O service provider instances. Service provider classes may be discovered at runtime by the mechanisms documented in ServiceLoader. The intent is that it be relatively inexpensive to load and inspect all available Image I/O service provider classes. These classes may then be used to locate and instantiate more heavyweight classes that will perform actual work, in this case instances of ImageReader, ImageWriter, ImageTranscoder, ImageInputStream, and ImageOutputStream. Service providers included in the Java runtime are automatically loaded as soon as this class is instantiated.

When the registerApplicationClasspathSpis method is called, additional service provider instances will be discovered using ServiceLoader.

It is also possible to manually add service providers not found automatically, as well as to remove those that are using the interfaces of the ServiceRegistry class. Thus the application may customize the contents of the registry as it sees fit.

For information on how to create and deploy service providers, refer to the documentation on ServiceLoader

  • Method Details

    • getDefaultInstance

      public static IIORegistry getDefaultInstance()
      Returns the default IIORegistry instance used by the Image I/O API. This instance should be used for all registry functions.

      Each ThreadGroup will receive its own instance; this allows different Applets in the same browser (for example) to each have their own registry.

      the default registry for the current ThreadGroup.
    • registerApplicationClasspathSpis

      public void registerApplicationClasspathSpis()
      Registers all available service providers found on the application class path, using the default ClassLoader. This method is typically invoked by the ImageIO.scanForPlugins method.
      See Also:
      ImageIO.scanForPlugins(), ClassLoader.getResources(java.lang.String)