Extract Files from PDF Portfolio in Java

import com.spire.pdf.PdfDocument;
import com.spire.pdf.attachments.PdfAttachment;

import java.io.*;

public class ReadPortfolio {
    public static void main(String []args) throws IOException {
        //Create a PdfDocument instance
        PdfDocument pdf = new PdfDocument();
        //Load the PDF file
        pdf.loadFromFile("Portfolio.pdf");

        //Loop through the attachments in the file
       for(Object obj : pdf.getAttachments()) {
            PdfAttachment attachment = (PdfAttachment) obj;
            //Extract files
            String fileName = attachment.getFileName();
            OutputStream fos = new FileOutputStream("extract/" + fileName);
            fos.write(attachment.getData());
        }

        pdf.dispose();
    }
}