Sending a Barcode to a Zebra Printer from a Java Application

Not every Zebra printer has ZPL II, but then you can use EPL

EPL2 programming guide for Zebra.pdf (Link in comment section)

Code sample:

private static boolean printLabel(PrintService printService, String label) {
    if (printService == null || label == null) {
        System.err.println("[Print Label] print service or label is invalid.");
        return false;
    }
    String czas = new SimpleDateFormat("d MMMMM yyyy'r.' HH:mm s's.'").format(new Date());
    String command =  
            "N\n"+
            "A50,50,0,2,2,2,N,\""+label+"\"\n"+
            "B50,100,0,1,2,2,170,B,\""+label+"\"\n"+
            "A50,310,0,3,1,1,N,\""+czas+"\"\n"+
            "P1\n"
            ;
    
    byte[] data;
    data = command.getBytes(StandardCharsets.US_ASCII);
    Doc doc = new SimpleDoc(data, DocFlavor.BYTE_ARRAY.AUTOSENSE, null);
    
    boolean result = false;
    try {
        printService.createPrintJob().print(doc, null);
        result = true;
    } catch (PrintException e) {
        e.printStackTrace();
    }
    return result;
}

There are two ways to work with Zebra printers. The first is to print as on regular printer. Java printing basics are well explained in official tutorial. End of page will treated by printer as end of sticker. The disadvantage of this approach is that all painting must be done by hands. I.e. you can't use internal printer's barcoding ability.

The second is to write ZPL commands directly to printer. Something like this:

PrintService pservice = ... // acquire print service of your printer
DocPrintJob job = pservice.createPrintJob();  
String commands = "^XA\n\r^MNM\n\r^FO050,50\n\r^B8N,100,Y,N\n\r^FD1234567\n\r^FS\n\r^PQ3\n\r^XZ";
DocFlavor flavor = DocFlavor.BYTE_ARRAY.AUTOSENSE;
Doc doc = new SimpleDoc(commands.getBytes(), flavor, null);
job.print(doc, null);

The disadvantage is that you need to learn ZPL - Zebra Programming Language. Although it is simple enough, but such things as images and custom fonts could make you headache. Programming manuals are freely available on Zebra site: Part 1 and Part 2.