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src/java.desktop/share/classes/javax/print/MultiDoc.java

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*** 1,7 **** /* ! * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this --- 1,7 ---- /* ! * Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this
*** 26,136 **** package javax.print; import java.io.IOException; /** ! * Interface MultiDoc specifies the interface for an object that supplies more ! * than one piece of print data for a Print Job. "Doc" is a short, * easy-to-pronounce term that means "a piece of print data," and a "multidoc" ! * is a group of several docs. The client passes to the Print Job an object ! * that implements interface MultiDoc, and the Print Job calls methods on * that object to obtain the print data. ! * <P> ! * Interface MultiDoc provides an abstraction similar to a "linked list" of ! * docs. A multidoc object is like a node in the linked list, containing the * current doc in the list and a pointer to the next node (multidoc) in the ! * list. The Print Job can call the multidoc's {@link #getDoc() ! * getDoc()} method to get the current doc. When it's ready to go ! * on to the next doc, the Print Job can call the multidoc's {@link #next() ! * next()} method to get the next multidoc, which contains the ! * next doc. So Print Job code for accessing a multidoc might look like this: ! * <PRE> * void processMultiDoc(MultiDoc theMultiDoc) { * * MultiDoc current = theMultiDoc; ! * while (current != null) { * processDoc (current.getDoc()); * current = current.next(); * } * } ! * </PRE> ! * <P> ! * Of course, interface MultiDoc can be implemented in any way that fulfills ! * the contract; it doesn't have to use a linked list in the implementation. ! * <P> ! * To get all the print data for a multidoc print job, a Print Service ! * proxy could use either of two patterns: ! * <OL TYPE=1> ! * <LI> ! * The <B>interleaved</B> pattern: Get the doc from the current multidoc. Get ! * the print data representation object from the current doc. Get all the print ! * data from the print data representation object. Get the next multidoc from ! * the current multidoc, and repeat until there are no more. (The code example ! * above uses the interleaved pattern.) ! * ! * <LI> ! * The <B>all-at-once</B> pattern: Get the doc from the current multidoc, and ! * save the doc in a list. Get the next multidoc from the current multidoc, and ! * repeat until there are no more. Then iterate over the list of saved docs. Get ! * the print data representation object from the current doc. Get all the print ! * data from the print data representation object. Go to the next doc in the ! * list, and repeat until there are no more. ! * </OL> * Now, consider a printing client that is generating print data on the fly and * does not have the resources to store more than one piece of print data at a * time. If the print service proxy used the all-at-once pattern to get the * print data, it would pose a problem for such a client; the client would have * to keep all the docs' print data around until the print service proxy comes * back and asks for them, which the client is not able to do. To work with such * a client, the print service proxy must use the interleaved pattern. ! * <P> * To address this problem, and to simplify the design of clients providing ! * multiple docs to a Print Job, every Print Service proxy that supports ! * multidoc print jobs is required to access a MultiDoc object using the ! * interleaved pattern. That is, given a MultiDoc object, the print service ! * proxy will call {@link #getDoc() getDoc()} one or more times ! * until it successfully obtains the current Doc object. The print service proxy * will then obtain the current doc's print data, not proceeding until all the * print data is obtained or an unrecoverable error occurs. If it is able to ! * continue, the print service proxy will then call {@link #next() ! * next()} one or more times until it successfully obtains either ! * the next MultiDoc object or an indication that there are no more. An ! * implementation of interface MultiDoc can assume the print service proxy will ! * follow this interleaved pattern; for any other pattern of usage, the MultiDoc ! * implementation's behavior is unspecified. ! * <P> * There is no restriction on the number of client threads that may be * simultaneously accessing the same multidoc. Therefore, all implementations of * interface MultiDoc must be designed to be multiple thread safe. In fact, a * client thread could be adding docs to the end of the (conceptual) list while * a Print Job thread is simultaneously obtaining docs from the beginning of the * list; provided the multidoc object synchronizes the threads properly, the two ! * threads will not interfere with each other */ - public interface MultiDoc { - /** * Obtain the current doc object. * ! * @return Current doc object. ! * ! * @exception IOException ! * Thrown if a error occurred reading the document. */ public Doc getDoc() throws IOException; /** * Go to the multidoc object that contains the next doc object in the * sequence of doc objects. * ! * @return Multidoc object containing the next doc object, or null if ! * there are no further doc objects. ! * ! * @exception IOException ! * Thrown if an error occurred locating the next document */ public MultiDoc next() throws IOException; - } --- 26,127 ---- package javax.print; import java.io.IOException; /** ! * Interface {@code MultiDoc} specifies the interface for an object that ! * supplies more than one piece of print data for a Print Job. "Doc" is a short, * easy-to-pronounce term that means "a piece of print data," and a "multidoc" ! * is a group of several docs. The client passes to the Print Job an object that ! * implements interface {@code MultiDoc}, and the Print Job calls methods on * that object to obtain the print data. ! * <p> ! * Interface {@code MultiDoc} provides an abstraction similar to a "linked list" ! * of docs. A multidoc object is like a node in the linked list, containing the * current doc in the list and a pointer to the next node (multidoc) in the ! * list. The Print Job can call the multidoc's {@link #getDoc() getDoc()} method ! * to get the current doc. When it's ready to go on to the next doc, the Print ! * Job can call the multidoc's {@link #next() next()} method to get the next ! * multidoc, which contains the next doc. So Print Job code for accessing a ! * multidoc might look like this: ! * ! * <pre> * void processMultiDoc(MultiDoc theMultiDoc) { * * MultiDoc current = theMultiDoc; ! * * while (current != null) { * processDoc (current.getDoc()); * current = current.next(); * } * } ! * </pre> ! * Of course, interface {@code MultiDoc} can be implemented in any way that ! * fulfills the contract; it doesn't have to use a linked list in the ! * implementation. ! * <p> ! * To get all the print data for a multidoc print job, a Print Service proxy ! * could use either of two patterns: ! * <ol type=1> ! * <li>The <b>interleaved</b> pattern: Get the doc from the current multidoc. ! * Get the print data representation object from the current doc. Get all the ! * print data from the print data representation object. Get the next multidoc ! * from the current multidoc, and repeat until there are no more. (The code ! * example above uses the interleaved pattern.) ! * <li>The <b>all-at-once</b> pattern: Get the doc from the current multidoc, ! * and save the doc in a list. Get the next multidoc from the current ! * multidoc, and repeat until there are no more. Then iterate over the list of ! * saved docs. Get the print data representation object from the current doc. ! * Get all the print data from the print data representation object. Go to the ! * next doc in the list, and repeat until there are no more. ! * </ol> * Now, consider a printing client that is generating print data on the fly and * does not have the resources to store more than one piece of print data at a * time. If the print service proxy used the all-at-once pattern to get the * print data, it would pose a problem for such a client; the client would have * to keep all the docs' print data around until the print service proxy comes * back and asks for them, which the client is not able to do. To work with such * a client, the print service proxy must use the interleaved pattern. ! * <p> * To address this problem, and to simplify the design of clients providing ! * multiple docs to a Print Job, every Print Service proxy that supports ! * multidoc print jobs is required to access a {@code MultiDoc} object using the ! * interleaved pattern. That is, given a {@code MultiDoc} object, the print ! * service proxy will call {@link #getDoc() getDoc()} one or more times until it ! * successfully obtains the current {@code Doc} object. The print service proxy * will then obtain the current doc's print data, not proceeding until all the * print data is obtained or an unrecoverable error occurs. If it is able to ! * continue, the print service proxy will then call {@link #next() next()} one ! * or more times until it successfully obtains either the next {@code MultiDoc} ! * object or an indication that there are no more. An implementation of ! * interface {@code MultiDoc} can assume the print service proxy will follow ! * this interleaved pattern; for any other pattern of usage, the ! * {@code MultiDoc} implementation's behavior is unspecified. ! * <p> * There is no restriction on the number of client threads that may be * simultaneously accessing the same multidoc. Therefore, all implementations of * interface MultiDoc must be designed to be multiple thread safe. In fact, a * client thread could be adding docs to the end of the (conceptual) list while * a Print Job thread is simultaneously obtaining docs from the beginning of the * list; provided the multidoc object synchronizes the threads properly, the two ! * threads will not interfere with each other. */ public interface MultiDoc { /** * Obtain the current doc object. * ! * @return current doc object ! * @throws IOException if an error occurred when reading the document */ public Doc getDoc() throws IOException; /** * Go to the multidoc object that contains the next doc object in the * sequence of doc objects. * ! * @return multidoc object containing the next doc object, or {@code null} ! * if there are no further doc objects ! * @throws IOException if an error occurred locating the next document */ public MultiDoc next() throws IOException; }
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