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java - Printing with Attributes(Tray Control, Duplex, etc...) using javax.print library

问题描述:

I've been trying for some time to determine a way to use the standard Java Print library to print files - specifically, PDF documents - with certain attributes - specifically, to certain trays or using duplex.

There exists plenty of documentation on how this should be done, and indeed, I've researched and tried these methods. The typical way is something like this:

public static void main (String [] args) {

try {

PrintService[] pservices = PrintServiceLookup.lookupPrintServices(null, null);

//Acquire Printer

PrintService printer = null;

for (PrintService serv: pservices) {

System.out.println(serv.toString());

if (serv.getName().equals("PRINTER_NAME_BLAH")) {

printer = serv;

}

}

if (printer != null) {

System.out.println("Found!");

//Open File

FileInputStream fis = new FileInputStream("FILENAME_BLAH_BLAH.pdf");

//Create Doc out of file, autosense filetype

Doc pdfDoc = new SimpleDoc(fis, DocFlavor.INPUT_STREAM.AUTOSENSE, null);

//Create job for printer

DocPrintJob printJob = printer.createPrintJob();

//Create AttributeSet

PrintRequestAttributeSet pset = new HashPrintRequestAttributeSet();

//Add MediaTray to AttributeSet

pset.add(MediaTray.TOP);

//Add Duplex Option to AttributeSet

pset.add(Sides.DUPLEX);

//Print using Doc and Attributes

printJob.print(pdfDoc, pset);

//Close File

fis.close();

}

}

catch (Throwable t) {

t.printStackTrace();

}

}

In short, you do the following

  1. Find the Printer
  2. Create a PrinterJob
  3. Create an AttributeSet
  4. Add Attributes to the AttributeSet, such as Tray and Duplex
  5. Call print on the printer job using the AttributeSet

The problem here is that, despite being the documented way of doing this, as well as what I've found from several tutorials, this method... doesn't work. Now keep in mind, I know that doesn't sound very descript, but hear me out. I don't say that lightly...

The official documentation for PrinterJob actually mentions that the AttributeSet is ignored in the default implementation. Source code seen here shows this to be true - the attributes are passed in and ignored entirely.

So apparently, you need some sort of extended version of the class, which is possibly based on the specific printers and their capabilities? I attempted to write some test code that would tell me such capabilities - we have a large variety of printers set up at the office, large or small, simple or full of bells and whistles - not to mention several drivers on my computer just for pseudo-printer drivers that just create documents and simulate printers without going to any sort of hardware. The test code is as follows:

public static void main (String [] args) {

PrintService[] pservices = PrintServiceLookup.lookupPrintServices(null, null);

for (PrintService serv: pservices) {

System.out.println(serv.toString());

printFunctionality(serv, "Trays", MediaTray.class);

printFunctionality(serv, "Copies", Copies.class);

printFunctionality(serv, "Print Quality", PrintQuality.class);

printFunctionality(serv, "Color", ColorSupported.class);

printFunctionality(serv, "Media Size", MediaSize.class);

printFunctionality(serv, "Accepting Jobs", PrinterIsAcceptingJobs.class);

}

}

private static void printFunctionality(PrintService serv, String attrName, Class<? extends Attribute> attr) {

boolean isSupported = serv.isAttributeCategorySupported(attr);

System.out.println(" " + attrName + ": " + (isSupported ? "Y" : "N"));

}

The results I found were that every printer, without exception, returned that "copies" were supported, and all other attributes were not. Furthermore, every printer's capabilities were identical, regardless of how implausible that would seem.

The inevitable question is multi-layered: How does one send in attributes in a way that they are registered? Additionally, how does one properly detect the capabilities of a printer? Indeed, is the PrinterJob class actually extended in a usable way at all, or are the Attributes always ignored?

Examples I've found throughout The Internet seem to suggest to me that the answer to the latter question is "No, they are always ignored", which seems ridiculous to me (but increasingly more believable as I sift through hundreds of pages). Is this code that Sun simply set up but never got working to a completed state? If so, are there any alternatives?

网友答案:

The problem is that the the Java print API is a bridge between worlds. Printer manufacturers don't release drivers for the JVM. They release drivers for Windows, Macintosh, and maybe someone has a a driver for a given printer that works on one or more *nix platforms.

Along you come with some Java code running inside a JVM on some host system. When you start querying the printer features, you aren't talking to the printers -- you are talking to a bridge class in java.awt.print that hook into the JVM, which hooks to the host operating system, which hooks into whatever particular driver was installed for a given printer. So there are several places where this can fall apart... The particular JVM you are on may or may not fully implement the API for querying printer features, let alone passing those parameters along for a given job.

A few suggestions:

  1. look into the javax.print classes as an alternative to java.awt.print -- I've had more luck printing from there.
  2. try using alternative print drivers for your printers -- you can define multiple named connections to a given printer, each with a different driver. If you've got a manufacturer provided driver, try a more generic driver, if you've got a generic driver, try to install a more specific one.
  3. run your code under alternate JVM implementations for your platform
网友答案:

So, we inevitably found a way to print to different trays and with different settings, but not directly. We found it impossible to send attributes via the printJob.print method, and that much hasn't changed. However, we were able to set the name of the print job, then intercept the print job with a low-level Perl script, parse the name, and set the tray and duplex settings there. It's an extreme hack, but it works. It still remains true that Java Printer Attributes do not work, and you will need to find another way if you want to set them.

网友答案:

We had similar requirement to print PDF's and wanted to send some pages to Specific tray and also wanted the document to be stapled. We used Java code + ghost script combination First convert PDF to ghost script and then add PJL (Print job language) commands to ghost script file to select trays and staple the documents. Then send that edited ghost script file to printer.

Here is complete example written in Java

http://reddymails.blogspot.com/2014/07/how-to-print-documents-using-java-how.html

-Ram

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