如何防止PDFBox 1.8的打印在打印文档的顶部留下空白？

Question

我使用PDFBox (1.8.12)从java打印pdf文档：

PDDocument pdf = PDDocument.load(new File(args[0]));
PrinterJob job = PrinterJob.getPrinterJob();

PrintRequestAttributeSet attr_set = new HashPrintRequestAttributeSet();
attr_set.add(MediaSizeName.ISO_A4); // <<< supposedly prints in A4 format
attr_set.add(Sides.ONE_SIDED);

PDPageable p = new PDPageable(pdf);


job.setPageable(p);

PrintService ps = null;
for  (PrintService i : PrintServiceLookup.lookupPrintServices(null,null)) {
    if (i.getName().equals(args[1])) {
        ps = i;
    }
}

if (ps == null) {
    try {
        throw new SystemException(ErrorCode.NO_PRINTER_FOUND);
    } catch (SystemException e) {
        e.printStackTrace();
    }
}
else
{

    job.setPrintService(ps);
    job.print(attr_set);

}

问题是，印刷的文件有一个空白，我不知道为什么。我进行了测试，将pdf循环回pdf虚拟打印机，看起来是一样的，我认为这意味着PDFbox不会错误地处理pdf。

经过进一步的研究，印刷纸上的文字似乎被放大了，开始的更高，完成的比原来的更低(当我直接从具体的打印机打印)。

我打印的纸张是A4格式，所以我尝试像上面那样将格式设置为A4，但问题仍然存在。

Answer 1

我找到了这个解决方案：

PDFPageable p = new PDFPageable(pdf);
PDFPrintable printable = new PDFPrintable(pdf,Scaling.SCALE_TO_FIT);

job.setPageable(p);
job.setPrintable(printable);

应用正确的格式。如果我必须删除它，我将进行编辑，但现在，我将把全部内容发布在github：PDFBOX)上。

如果我犯了一个错误，请随时提出/评论/帮助。

在这里，我做了上述代码的摘录：

package com.pierreantoineguillaume;

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

import javax.print.PrintService;
import javax.print.PrintServiceLookup;
import javax.print.attribute.HashPrintRequestAttributeSet;
import javax.print.attribute.PrintRequestAttributeSet;
import javax.print.attribute.standard.MediaSizeName;
import java.awt.print.PrinterException;
import java.awt.print.PrinterJob;
import java.io.File;
import java.io.IOException;
import java.util.NoSuchElementException;
import java.util.Optional;

public class BasicPrinter {

    public static void main(String[] args) {
        BasicPrinter basicPrinter = new BasicPrinter();
        String printerName = "name of my printer";
        String filename = "my file to print";

        try {
            Optional<PrintService> printService = basicPrinter.getMatchingPrintService(printerName);
            basicPrinter.printA4(printService.get(), PDDocument.load(new File(filename)));
        } catch (NoSuchElementException e) {
            System.err.println("Could not locate printer " + printerName);
        } catch (PrinterException e) {
            System.err.println("Could not print file because some error occurred during the print job or a compatibility error with the service");
        } catch (IOException e) {
            System.err.println("Could not find file to print");
        }
    }

    public void printA4(PrintService printer, PDDocument documentToPrint) throws PrinterException {

        PrinterJob job = PrinterJob.getPrinterJob();

        job.setPageable(new PDFPageable(documentToPrint));
        job.setPrintable(new PDFPrintable(documentToPrint, Scaling.SCALE_TO_FIT));


        job.setPrintService(printer);
        job.print(getA4Attributes());
    }

    public Optional<PrintService> getMatchingPrintService(String printerName) {
        for (PrintService i : PrintServiceLookup.lookupPrintServices(null, getA4Attributes())) {
            if (i.getName().equals(printerName)) {
                return Optional.of(i);
            }
        }

        return Optional.empty();
    }

    private PrintRequestAttributeSet getA4Attributes() {
        PrintRequestAttributeSet attr_set = new HashPrintRequestAttributeSet();
        attr_set.add(MediaSizeName.ISO_A4);
        return attr_set;
    }
}