printerjob.java

JAVA基本类源代码,大家可以学习学习!

/*
 * @(#)PrinterJob.java	1.34 03/01/23
 *
 * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package java.awt.print;

import java.awt.AWTError;
import java.awt.HeadlessException;
import java.util.Enumeration;

import javax.print.DocFlavor;
import javax.print.PrintService;
import javax.print.PrintServiceLookup;
import javax.print.StreamPrintServiceFactory;
import javax.print.attribute.PrintRequestAttributeSet;

import sun.security.action.GetPropertyAction;

/**
 * The <code>PrinterJob</code> class is the principal class that controls
 * printing. An application calls methods in this class to set up a job,
 * optionally to invoke a print dialog with the user, and then to print
 * the pages of the job.
 */
public abstract class PrinterJob {

 /* Public Class Methods */

    /**
     * Creates and returns a <code>PrinterJob</code> which is initially
     * associated with the default printer.
     * If no printers are available on the system, a PrinterJob will still
     * be returned from this method, but <code>getPrintService()</code> 
     * will return <code>null</code>, and calling 
     * {@link #print() print} with this <code>PrinterJob</code> might 
     * generate an exception.  Applications that need to determine if
     * there are suitable printers before creating a <code>PrinterJob</code> 
     * should ensure that the array returned from 
     * {@link #lookupPrintServices() lookupPrintServices} is not empty.
     * @return a new <code>PrinterJob</code>.
     */
    public static PrinterJob getPrinterJob() {
	SecurityManager security = System.getSecurityManager();
	if (security != null) {
	    security.checkPrintJobAccess();
	}
	return (PrinterJob) java.security.AccessController.doPrivileged(
	    new java.security.PrivilegedAction() {
	    public Object run() {
		String nm = System.getProperty("java.awt.printerjob", null);
		try {
		    return (PrinterJob)Class.forName(nm).newInstance();
		} catch (ClassNotFoundException e) {
		    throw new AWTError("PrinterJob not found: " + nm);
		} catch (InstantiationException e) {
		 throw new AWTError("Could not instantiate PrinterJob: " + nm);
		} catch (IllegalAccessException e) {
		    throw new AWTError("Could not access PrinterJob: " + nm);
		}
	    }
	});
    }
    
    /**
     * A convenience method which looks up 2D print services.
     * Services returned from this method may be installed on
     * <code>PrinterJob</code>s which support print services.
     * Calling this method is equivalent to calling
     * {@link javax.print.PrintServiceLookup#lookupPrintServices(
     * DocFlavor, AttributeSet) 
     * <code>PrintServiceLookup.lookupPrintServices()</code>}
     * and specifying a Pageable DocFlavor.
     * @return a possibly empty array of 2D print services.
     * @since     1.4
     */
    public static PrintService[] lookupPrintServices() {
	return PrintServiceLookup.
	    lookupPrintServices(DocFlavor.SERVICE_FORMATTED.PAGEABLE, null);
    }

   
    /**
     * A convenience method which locates factories for stream print
     * services which can image 2D graphics.
     * Sample usage :
     * <pre>
     * FileOutputStream outstream;
     * StreamPrintService psPrinter;
     * String psMimeType = "application/postscript";
     *
     * StreamPrintServiceFactory[] factories =
     *     PrinterJob.lookupStreamPrintServices(psMimeType);
     * if (factories.length > 0) {
     *     try {
     *         outstream = new File("out.ps");
     *         psPrinter =  factories[0].getPrintService(fos);
     *         // psPrinter can now be set as the service on a PrinterJob 
     *     } catch (FileNotFoundException e) {
     *     }
     * }            
     * </pre>
     * Services returned from this method may be installed on
     * <code>PrinterJob</code> instances which support print services.
     * Calling this method is equivalent to calling
     * {@link javax.print.StreamPrintServiceFactory#lookupStreamPrintServiceFactories(DocFlavor, String)
     * <code>StreamPrintServiceFactory.lookupStreamPrintServiceFactories()
     * </code>} and specifying a Pageable DocFlavor.
     * 
     * @param mimeType the required output format, or null to mean any format.
     * @return a possibly empty array of 2D stream print service factories.
     * @since     1.4
     */
    public static StreamPrintServiceFactory[]
	lookupStreamPrintServices(String mimeType) {
	return StreamPrintServiceFactory.lookupStreamPrintServiceFactories(
				       DocFlavor.SERVICE_FORMATTED.PAGEABLE,
				       mimeType);
    }
				  
    
 /* Public Methods */

    /**
     * A <code>PrinterJob</code> object should be created using the
     * static {@link #getPrinterJob() <code>getPrinterJob</code>} method.
     */
    public PrinterJob() {
    }

    /**
     * Returns the service (printer) for this printer job.
     * Implementations of this class which do not support print services
     * may return null;
     * @return the service for this printer job.
     * @see #setPrintService(PrintService)
     * @since     1.4
     */
    public PrintService getPrintService() {
	return null;
    }

    /**
     * Associate this PrinterJob with a new PrintService.
     * This method is overridden by subclasses which support
     * specifying a Print Service.
     *
     * Throws <code>PrinterException</code> if the specified service
     * cannot support the <code>Pageable</code> and
     * <code>Printable</code> interfaces necessary to support 2D printing.
     * @param service a print service that supports 2D printing
     * @exception PrinterException if the specified service does not support
     * 2D printing, or this PrinterJob class does not support
     * setting a 2D print service, or the specified service is
     * otherwise not a valid print service.
     * @see #getPrintService
     * @since     1.4
     */
    public void setPrintService(PrintService service)
	throws PrinterException {
	    throw new PrinterException(
			 "Setting a service is not supported on this class");
    }
     
    /**
     * Calls <code>painter</code> to render the pages.  The pages in the
     * document to be printed by this 
     * <code>PrinterJob</code> are rendered by the {@link Printable}
     * object, <code>painter</code>.  The {@link PageFormat} for each page
     * is the default page format.
     * @param painter the <code>Printable</code> that renders each page of
     * the document.
     */
    public abstract void setPrintable(Printable painter);

    /**
     * Calls <code>painter</code> to render the pages in the specified
     * <code>format</code>.  The pages in the document to be printed by
     * this <code>PrinterJob</code> are rendered by the
     * <code>Printable</code> object, <code>painter</code>. The
     * <code>PageFormat</code> of each page is <code>format</code>.
     * @param painter the <code>Printable</code> called to render
     *		each page of the document
     * @param format the size and orientation of each page to
     *                   be printed
     */
    public abstract void setPrintable(Printable painter, PageFormat format);

    /**
     * Queries <code>document</code> for the number of pages and 
     * the <code>PageFormat</code> and <code>Printable</code> for each
     * page held in the <code>Pageable</code> instance,  
     * <code>document</code>.
     * @param document the pages to be printed. It can not be
     * <code>null</code>.
     * @exception NullPointerException the <code>Pageable</code> passed in
     * was <code>null</code>.
     * @see PageFormat
     * @see Printable
     */
    public abstract void setPageable(Pageable document)
	throws NullPointerException;

    /**
     * Presents a dialog to the user for changing the properties of
     * the print job.
     * This method will display a native dialog if a native print
     * service is selected, and user choice of printers will be restricted
     * to these native print services.
     * To present the cross platform print dialog for all services,
     * including native ones instead use
     * <code>printDialog(PrintRequestAttributeSet)</code>.
     * <p>
     * PrinterJob implementations which can use PrintService's will update
     * the PrintService for this PrinterJob to reflect the new service
     * selected by the user.
     * @return <code>true</code> if the user does not cancel the dialog;
     * <code>false</code> otherwise.
     * @exception HeadlessException if GraphicsEnvironment.isHeadless()
     * returns true.
     * @see java.awt.GraphicsEnvironment#isHeadless
     */
    public abstract boolean printDialog() throws HeadlessException;

    /**
     * A convenience method which displays a cross-platform print dialog
     * for all services which are capable of printing 2D graphics using the
     * <code>Pageable</code> interface. The selected printer when the
     * dialog is initially displayed will reflect the print service currently
     * attached to this print job.
     * If the user changes the print service, the PrinterJob will be
     * updated to reflect this, unless the user cancels the dialog.
     * As well as allowing the user to select the destination printer,
     * the user can also select values of various print request attributes.
     * <p>
     * The attributes parameter on input will reflect the applications
     * required initial selections in the user dialog. Attributes not
     * specified display using the default for the service. On return it
     * will reflect the user's choices. Selections may be updated by
     * the implementation to be consistent with the supported values
     * for the currently selected print service.