Class PreloaderImageIO

  • All Implemented Interfaces:
    ImagePreloader

    public class PreloaderImageIO
    extends AbstractImagePreloader
    Image preloader for images supported by ImageIO.

    Note: The implementation relies on the presence of a working ImageIO implementation which provides accurate image metadata. This is particularly important for PNG image because the PNG loader relies on that.

    • Constructor Detail

      • PreloaderImageIO

        public PreloaderImageIO()
    • Method Detail

      • preloadImage

        public ImageInfo preloadImage​(java.lang.String uri,
                                      javax.xml.transform.Source src,
                                      ImageContext context)
                               throws java.io.IOException,
                                      ImageException
        "Preloads" an image, i.e. indentifies whether the source image is supported by this implementation and determines the image's intrinsic size and possibly some additional information. The image is usually not fully loaded at this time to conserve memory. The method returns null if the image was not identified. An ImageException is only thrown if the image is identified but some error has happened while working on the file.
        Parameters:
        uri - the original (unresolved) URI of the image
        src - a image source the image is loaded from
        context - the context object that provides configuration information
        Returns:
        an image info object with the basic information about an image or null if the image is not supported by this implementation
        Throws:
        ImageException
        java.io.IOException - if an I/O error occurs while preloading the image