PrinterQueue

March 15, 1996

Inherits from Object
Defined in Printing.Def

Class Description

Class PrinterQueue provides the fundamental features for spooling print jobs to the printer queue. An instance of PrinterQueue exists for each available printer. The primary purpose of PrinterQueue is to take a file and image it.

Programming information

Instantiate: rarely
Subclass: rarely
Call its methods: rarely

If you're creating a new type of printer, you'll subclass PrinterQueue so you can control how the image is send to the printer. The AddToSendQueue method will most likely be the only method that you ever have to deal with directly, since most printing is user invoked.

Methods defined by class PrinterQueue

Class PrinterQueue defines the following methods:

Method	Description
Abort	Called by "Stop" button in StatusAnnouncement
AddToSendQueue	Submits a job for printing
PrintPixelMap	Print PixelMap from stream. Abstract
StartPrintJob	Starts the next job in the queue. Called by the spooler

Attributes defined by class PrinterQueue

Class PrinterQueue defines the following attribute:

Attribute	Type	Description
PrototypePrintJob	PrintJob	The size of the canvas

Fields defined by class PrinterQueue

Class PrinterQueue defines the following fields:

Field	Type	Description
spooler	PrintServer	Actor that gets dynamically created to spool a job
jobs	FixedList	List of rendered PixelMaps andthe params waiting to be	printed
prototypePrintJob	PrintJob	PrintJob prototype for this printer
image	Image	Image representing printer type
printerBusy	Semaphore	Used internally to manage print jobs

Method Descriptions

AddToSendQueue

operation AddToSendQueue(printJob: Object), safe;

submit job for printing