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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
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 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package javax.print;

/**
 * This interface is used by a printing application to cancel a print job. This
 * interface extends {@link DocPrintJob}. A {@code DocPrintJob} implementation
 * returned from a print service implements this interface if the print job can
 * be cancelled. Before trying to cancel a print job, the client needs to test
 * if the {@code DocPrintJob} object returned from the print service actually
 * implements this interface. Clients should never assume that a
 * {@code DocPrintJob} implements this interface. A print service might support
 * cancellation only for certain types of print data and representation class
 * names. This means that only some of the {@code DocPrintJob} objects returned
 * from a service will implement this interface.
 * <p>
 * Service implementors are encouraged to implement this optional interface and
 * to deliver a {@link javax.print.event.PrintJobEvent#JOB_CANCELED} event to
 * any listeners if a job is successfully cancelled with an implementation of
 * this interface. Services should also note that an implementation of this
 * method may be made from a separate client thread than that which made the
 * print request. Thus the implementation of this interface must be made thread
 * safe.
 */
public interface CancelablePrintJob extends DocPrintJob {

    /**
     * Stops further processing of a print job.
     * <p>
     * If a service supports this method it cannot be concluded that job
     * cancellation will always succeed. A job may not be able to be cancelled
     * once it has reached and passed some point in its processing. A successful
     * cancellation means only that the entire job was not printed, some portion
     * may already have printed when cancel returns.
     * <p>
     * The service will throw a {@code PrintException} if the cancellation did
     * not succeed. A job which has not yet been submitted for printing should
     * throw this exception. Cancelling an already successfully cancelled Print
     * Job is not considered an error and will always succeed.
     * <p>
     * Cancellation in some services may be a lengthy process, involving
     * requests to a server and processing of its print queue. Clients may wish
     * to execute cancel in a thread which does not affect application
     * execution.
     *
     * @throws PrintException if the job could not be successfully cancelled
     */
    public void cancel() throws PrintException;
}