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Java in a Nutshell

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18.51 java.awt.PrintJob (JDK 1.1)

A PrintJob object represents a single printing session or "job." The job may consist of one or more individual pages.

PrintJob is abstract so it cannot be instantiated directly. Instead, you must call the getPrintJob() method of the Toolkit object. Calling this method posts an appropriate print dialog box to request information from the user, such as which printer should be used. An application has no control over this process, but may pass a Properties object in which the dialog stores the user's printing preferences. This Properties object can then be reused when initiating subsequent print jobs.

Once a PrintJob object has been obtained from the Toolkit object, you call the getGraphics() method of PrintJob to obtain a Graphics object. Any drawing done with this Graphics object is printed rather than being displayed on-screen. The object returned by getGraphics() implements the PrintGraphics interface. Do not make any assumptions about the initial state of the Graphics object; in particular note that you must specify a font before you can draw any text.

When you are done drawing all the desired output on a page, call the dispose() method of the Graphics object to force the current page to be printed. You can call PrintJob.getGraphics() and Graphics.dispose() repeatedly to print any number of pages required by your application. Note, however, that if the lastPageFirst() method returns true, the user has requested that pages be printed in reverse order. It is up to your application to implement this feature.

The getPageDimension() method returns the size of the page in pixels. getPageResolution() returns the resolution of the page in pixels per inch. This resolution is closer to a screen resolution (70 to 100 pixels per inch) rather than a typical printer resolution (300 to 600 pixels per inch). This means that on-screen drawings can be drawn directly to the printer without scaling. It also means, however, that you cannot take full advantage of the extra resolution provided by printers.

When you are done with a PrintJob, and you have called dispose() on the Graphics object returned by getGraphics(), you should call end() to terminate the job.

public abstract class PrintJob extends Object {
    // Default Constructor: public PrintJob()
    // Public Instance Methods
            public abstract void end();
            public void finalize();  // Overrides Object
            public abstract Graphics getGraphics();
            public abstract Dimension getPageDimension();
            public abstract int getPageResolution();
            public abstract boolean lastPageFirst();
}

Returned By:

PrintGraphics.getPrintJob(), Toolkit.getPrintJob()


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