Java Printing Font Stretch

问题

I just got the printer to work in java how I need it too, but there's one last problem I need to solve. When it prints, the font's width is rather stretched, and not crisp and clear like it should be.

Here is my code my the actual drawing to the paper:

    FontMetrics metrics = graphics.getFontMetrics(font);
    int lineHeight = metrics.getHeight();

    arrangePage(graphics, pageFormat, lineHeight);

    if (page > pageBreaks.length){
        return NO_SUCH_PAGE;
    }

    Graphics2D g = (Graphics2D) graphics;

    g.translate(pageFormat.getImageableX(), pageFormat.getImageableY());
    g.setFont(font);

    int y = 0;
    int begin = 0;

    if (page == 0){
        begin = 0;
    }else begin = pageBreaks[page-1];

    int end = 0;

    if (page == pageBreaks.length){
        end = lines.length;
    }else end = pageBreaks[page];

    for (int line = begin; line < end; line++){
        y += lineHeight;
        g.drawString(lines[line], 0, y);
    }

    string = deepCopy;

    return PAGE_EXISTS;

How do I get rid of the stretching? It can be noted that this is based off this tutorial: http://docs.oracle.com/javase/tutorial/2d/printing/set.html

Any advice or help is greatly appreciated.

回答1:

The default DPI is normal 72 DPI (I believe), which, on printed paper, is pretty terrible. You need to prompt the print API to try and find a printer with a better DPI.

Basically you need to use the print services API.

Try something like...

public class PrintTest01 {

  public static void main(String[] args) {

    PrinterResolution pr = new PrinterResolution(300, 300, PrinterResolution.DPI);

    PrintRequestAttributeSet aset = new HashPrintRequestAttributeSet();
    aset.add(MediaSizeName.ISO_A4);
    aset.add(pr);
    aset.add(OrientationRequested.PORTRAIT);

    PrinterJob pj = PrinterJob.getPrinterJob();
    pj.setPrintable(new Page());
    try {
      pj.print(aset);
    } catch (PrinterException ex) {
      ex.printStackTrace();
    }

  }

  public static class Page implements Printable {

    @Override
    public int print(Graphics g, PageFormat pageFormat, int pageIndex) throws PrinterException {
      if (pageIndex > 0) {
        return NO_SUCH_PAGE;
      }

      Graphics2D g2d = (Graphics2D) g;
      g2d.translate(pageFormat.getImageableX(), pageFormat.getImageableY());

      g.setFont(new Font("Arial", Font.PLAIN, 128));
      FontMetrics fm = g.getFontMetrics();
      int x = (int)(pageFormat.getWidth() - fm.stringWidth("A")) / 2;
      int y = (int)((pageFormat.getHeight() - fm.getHeight()) / 2) + fm.getAscent();

      g2d.drawString("A", x, y);

      return PAGE_EXISTS;
    }
  }
}

You might find Working with Print Services and Attributes of some help...

I should warn you, this is going to print to the first print that it can find that meets the PrintRequestAttributeSet. You could also add in the print dialog to see what's it doing, but that's another level of complexity I can live without right now ;)

回答2:

The above worked! To open a print dialog with it, use this:

    PrinterJob job = PrinterJob.getPrinterJob();
    TextDocumentPrinter document = new TextDocumentPrinter();

    PrinterResolution pr = new PrinterResolution(300, 300, PrinterResolution.DPI);

    PrintRequestAttributeSet aset = new HashPrintRequestAttributeSet();
    aset.add(MediaSizeName.ISO_A4);
    aset.add(pr);
    aset.add(OrientationRequested.PORTRAIT);

    job.setPrintable(document);

    boolean doPrint = false;

    if (showDialog){
        doPrint = job.printDialog(aset);
    }else doPrint = true;

    if (doPrint){
        try{
            job.print();
        }catch(PrinterException e){
            e.printStackTrace();
        }
    }

The aset variable contains all of your new default values, and by plugging it into the printDialog, those are inputted into the printJob and consequently show up on the paper! They can be changed in the dialog, as well.

来源：https://stackoverflow.com/questions/14352243/java-printing-font-stretch