getStreamWrapper.java

    public static ImageStreamWrapper getStreamWrapper(Supplier<FormDataBodyPart> supplier) {
        return Optional.ofNullable(supplier.get())
        	.map(field -> {
        		InputStream is = field.getValueAs(InputStream.class);
        		long contentLength = getContentLength(field);

        		return new ImageStreamWrapper(is, contentLength);
        	}).orElse(null);
    }