javax.print

• Discover and select print services based on their capabilities
• Specify the format of print data
• Submit print jobs to services that support the document type to be printed.

Print Service Discovery

An application invokes the static methods of the abstract class {@link javax.print.PrintServiceLookup PrintServiceLookup} to locate print services that have the capabilities to satisfy the application's print request. For example, to print a double-sided document, the application first needs to find printers that have the double-sided printing capability.

The JDK includes PrintServiceLookup implementations that can locate the standard platform printers. To locate other types of printers, such as IPP printers or JINI printers, a print-service provider can write implementations of PrintServiceLookup. The print-service provider can dynamically install these PrintServiceLookup implementations using the SPI JAR file specification.

Attribute Definitions

The javax.print.attribute package describes the types of attributes and how they can be collected into sets. The javax.print.attribute.standard package enumerates all of the standard attributes supported by the API, most of which are implementations of attributes specified in the IETF Specification, RFC 2911 Internet Printing Protocol, 1.1: Model and Semantics, dated September 2000. The attributes specified in javax.print.attribute.standard include common capabilites, such as: resolution, copies, media sizes, job priority, and page ranges.

Document Type Specification

Using the API

1. Chooses a DocFlavor.
2. Creates a set of attributes.
3. Locates a print service that can handle the print request as specified by the DocFlavor and the attribute set.
4. Creates a {@link javax.print.Doc Doc} object encapsulating the DocFlavor and the actual print data, which can take many forms including: a Postscript file, a JPEG image, a URL, or plain text.
5. Gets a print job, represented by {@link javax.print.DocPrintJob DocPrintJob}, from the print service.
6. Calls the print method of the print job.

FileInputStream psStream;
try {
   psStream = new FileInputStream("file.ps");
} catch (FileNotFoundException ffne) {
}
if (psStream == null) {
    return;
}

DocFlavor psInFormat = DocFlavor.INPUT_STREAM.POSTSCRIPT;
Doc myDoc = new SimpleDoc(psStream, psInFormat, null);  
PrintRequestAttributeSet aset = 
	new HashPrintRequestAttributeSet();
aset.add(new Copies(5));
aset.add(MediaSize.A4);
aset.add(Sides.DUPLEX);
PrintService[] services = 
  PrintServiceLookup.lookupPrintServices(psInFormat, aset);
if (services.length > 0) {
   DocPrintJob job = services[0].createPrintJob();
   try {
	job.print(myDoc, aset);
   } catch (PrintException pe) {}
}

Please note: In the javax.print APIs, a null reference parameter to methods is incorrect unless explicitly documented on the method as having a meaningful interpretation. Usage to the contrary is incorrect coding and may result in a run time exception either immediately or at some later time. IllegalArgumentException and NullPointerException are examples of typical and acceptable run time exceptions for such cases.

@since 1.4

• MIME type. This is a Multipurpose Internet Mail Extensions (MIME) media type (as defined in RFC 2045 and RFC 2046) that specifies how the print data is to be interpreted. The charset of text data should be the IANA MIME-preferred name, or its canonical name if no preferred name is specified.

Multiple implementations may be installed concurrently. All implementations must be able to describe the located printers as instances of a PrintService.

The dialogs follow a standard pattern of acting as a continue/cancel option for a user as well as allowing the user to select the print service to use and specify choices such as paper size and number of copies.

The dialogs are designed to work with pluggable print services though the public APIs of those print services.

If a print service provides any vendor extensions these may be made accessible to the user through a vendor supplied tab panel Component. Such a vendor extension is encouraged to use Swing! and to support its accessibility APIs. The vendor extensions should return the settings as part of the AttributeSet. Applications which want to preserve the user settings should use those settings to specify the print job.

Note that a StreamPrintService is different from a PrintService, which supports a javax.print.attribute.standard.Destination Destination attribute.