JPEGImageWriter.java 文件源码

private boolean jfifOK(ImageTypeSpecifier imageType,
                       ImageWriteParam param,
                       IIOMetadata streamMetadata,
                       IIOMetadata imageMetadata) {
    // If the image type and metadata are JFIF compatible, return true
    if ((imageType != null) &&
        (!JPEG.isJFIFcompliant(imageType, true))) {
        return false;
    }
    if (imageMetadata != null) {
        JPEGMetadata metadata = null;
        if (imageMetadata instanceof JPEGMetadata) {
            metadata = (JPEGMetadata) imageMetadata;
        } else {
            metadata = (JPEGMetadata)convertImageMetadata(imageMetadata,
                                                          imageType,
                                                          param);
        }
        // metadata must have a jfif node
        if (metadata.findMarkerSegment
            (JFIFMarkerSegment.class, true) == null){
            return false;
        }
    }
    return true;
}