FileOutputStream equivalent

I am trying to rotate a pdf 180 degrees and I am using the ITextSharp library to do so. The code below is taken from their site's examples. However, I can't seem to find the right namespace to import to get the "FileOutputStream" to work. This is a console app, so not sure if Java's "FileOutpuStream" will work. The PDFStamper() is structured like this: PdfStamper(PDFReader reader, Stream os) ``` public void rotatePDF(string inputFile) { // get input document PdfReader reader = new PdfReader(inputFile); PdfName pdfName = new PdfName(inputFile); int n = reader.NumberOfPages; int rot; PdfDictionary pageDict; for (int i = 1; i <= n; i++) { rot = reader.GetPageRotation(i); pageDict = reader.GetPageN(i); pageDict.Put(PdfName.ROTATE, new PdfNumber(rot + 180)); } PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(inputFile)); stamper.closer(); reader.Close(); } ```