使用Java从PDF字节[]转换为PostScript

Question

我正在考虑从PDF作为字节[]创建PostScript文件，以发送到打印机。

我已经检查了这篇文章，Dustin的答复似乎与我需要的东西有些相似。 使用java从pdf转换为java

但是我得到的是一个字节[]将从FileOutputStream输出PDF。但是我想转换为Postscript。 我无法提及工作代码，有人可以建议吗？

import java.io.File;
import java.io.FileOutputStream;
import javax.print.DocFlavor;
import javax.print.DocPrintJob;
import javax.print.SimpleDoc;
import javax.print.StreamPrintService;
import javax.print.StreamPrintServiceFactory;
import javax.print.attribute.HashPrintRequestAttributeSet;
import javax.print.attribute.PrintRequestAttributeSet;

import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.printing.PDFPrintable;
import org.apache.pdfbox.printing.Scaling;

public class Printing {


        public static void main(String[] args) {
            try {
            DocFlavor flavor = DocFlavor.SERVICE_FORMATTED.PRINTABLE;
            String psMimeType = DocFlavor.BYTE_ARRAY.POSTSCRIPT.getMimeType();
            StreamPrintServiceFactory[] factories = StreamPrintServiceFactory.lookupStreamPrintServiceFactories(flavor, psMimeType);

            System.out.println ("Available PS services: " + factories.length);
            System.out.println ("Format: " + factories[0].getOutputFormat());

            FileOutputStream outStream = new FileOutputStream("/path/to/your.ps");
            StreamPrintService printService = factories[0].getPrintService(outStream);


            PrintRequestAttributeSet aset = new HashPrintRequestAttributeSet();
            aset.add(MediaSizeName.NA_LETTER);              

            PDDocument doc = PDDocument.load(new File("/path/to/my.pdf"));

            SimpleDoc pdfDoc = new SimpleDoc(new PDFPrintable(doc, Scaling.SCALE_TO_FIT, false), flavor, null);

            DocPrintJob newJob = printService.createPrintJob();
            newJob.print(pdfDoc, aset);

            outStream.close();

            }
            catch(Exception ex) {
                ex.printStackTrace();
            }
        }
}