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

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*** 1,7 **** /* ! * Copyright (c) 2000, 2014, 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
*** 23,205 **** * questions. */ package javax.print; - import java.io.InputStream; import java.io.IOException; import java.io.Reader; import javax.print.attribute.DocAttributeSet; - /** ! * Interface Doc specifies the interface for an object that supplies one piece ! * of print data for a Print Job. "Doc" is a short, easy-to-pronounce term * that means "a piece of print data." The client passes to the Print Job an ! * object that implements interface Doc, and the Print Job calls methods on ! * that object to obtain the print data. The Doc interface lets a Print Job: ! * <UL> ! * <LI> ! * Determine the format, or "doc flavor" (class {@link DocFlavor DocFlavor}), ! * in which the print data is available. A doc flavor designates the print ! * data format (a MIME type) and the representation class of the object ! * from which the print data comes. ! * ! * <LI> ! * Obtain the print data representation object, which is an instance of the ! * doc flavor's representation class. The Print Job can then obtain the actual ! * print data from the representation object. ! * ! * <LI> ! * Obtain the printing attributes that specify additional characteristics of ! * the doc or that specify processing instructions to be applied to the doc. ! * Printing attributes are defined in package {@link javax.print.attribute ! * javax.print.attribute}. The doc returns its printing attributes stored in ! * an {@link javax.print.attribute.DocAttributeSet javax.print.attribute.DocAttributeSet}. ! * </UL> ! * <P> ! * Each method in an implementation of interface Doc is permitted always to ! * return the same object each time the method is called. ! * This has implications ! * for a Print Job or other caller of a doc object whose print data * representation object "consumes" the print data as the caller obtains the * print data, such as a print data representation object which is a stream. ! * Once the Print Job has called {@link #getPrintData() ! * getPrintData()} and obtained the stream, any further calls to ! * {@link #getPrintData() getPrintData()} will return the same ! * stream object upon which reading may already be in progress, <I>not</I> a new ! * stream object that will re-read the print data from the beginning. Specifying ! * a doc object to behave this way simplifies the implementation of doc objects, ! * and is justified on the grounds that a particular doc is intended to convey ! * print data only to one Print Job, not to several different Print Jobs. (To ! * convey the same print data to several different Print Jobs, you have to ! * create several different doc objects on top of the same print data source.) ! * <P> ! * Interface Doc affords considerable implementation flexibility. The print data ! * might already be in existence when the doc object is constructed. In this ! * case the objects returned by the doc's methods can be supplied to the doc's ! * constructor, be stored in the doc ahead of time, and simply be returned when ! * called for. Alternatively, the print data might not exist yet when the doc ! * object is constructed. In this case the doc object might provide a "lazy" * implementation that generates the print data representation object (and/or * the print data) only when the Print Job calls for it (when the Print Job * calls the {@link #getPrintData() getPrintData()} method). ! * <P> * There is no restriction on the number of client threads that may be * simultaneously accessing the same doc. Therefore, all implementations of ! * interface Doc must be designed to be multiple thread safe. * <p> * However there can only be one consumer of the print data obtained from a ! * Doc. * <p> ! * If print data is obtained from the client as a stream, by calling Doc's ! * {@code getReaderForText()} or {@code getStreamForBytes()} ! * methods, or because the print data source is already an InputStream or ! * Reader, then the print service should always close these streams for the ! * client on all job completion conditions. With the following caveat. ! * If the print data is itself a stream, the service will always close it. ! * If the print data is otherwise something that can be requested as a stream, ! * the service will only close the stream if it has obtained the stream before ! * terminating. That is, just because a print service might request data as ! * a stream does not mean that it will, with the implications that Doc * implementors which rely on the service to close them should create such * streams only in response to a request from the service. - * <HR> */ public interface Doc { /** ! * Determines the doc flavor in which this doc object will supply its ! * piece of print data. * ! * @return Doc flavor. */ public DocFlavor getDocFlavor(); /** * Obtains the print data representation object that contains this doc ! * object's piece of print data in the format corresponding to the ! * supported doc flavor. ! * The {@code getPrintData()} method returns an instance of ! * the representation class whose name is given by {@link ! * #getDocFlavor() getDocFlavor()}.{@link ! * DocFlavor#getRepresentationClassName() ! * getRepresentationClassName()}, and the return value can be cast ! * from class Object to that representation class. ! * ! * @return Print data representation object. ! * ! * @exception IOException ! * Thrown if the representation class is a stream and there was an I/O ! * error while constructing the stream. */ public Object getPrintData() throws IOException; /** * Obtains the set of printing attributes for this doc object. If the * returned attribute set includes an instance of a particular attribute ! * <I>X,</I> the printer must use that attribute value for this doc, ! * overriding any value of attribute <I>X</I> in the job's attribute set. ! * If the returned attribute set does not include an instance ! * of a particular attribute <I>X</I> or if null is returned, the printer ! * must consult the job's attribute set to obtain the value for ! * attribute <I>X,</I> and if not found there, the printer must use an * implementation-dependent default value. The returned attribute set is * unmodifiable. * ! * @return Unmodifiable set of printing attributes for this doc, or null ! * to obtain all attribute values from the job's attribute ! * set. */ public DocAttributeSet getAttributes(); /** ! * Obtains a reader for extracting character print data from this doc. ! * The Doc implementation is required to support this method if the ! * DocFlavor has one of the following print data representation classes, ! * and return null otherwise: ! * <UL> ! * <LI> char[] ! * <LI> java.lang.String ! * <LI> java.io.Reader ! * </UL> * The doc's print data representation object is used to construct and ! * return a Reader for reading the print data as a stream of characters ! * from the print data representation object. ! * However, if the print data representation object is itself a Reader, ! * then the print data representation object is simply returned. ! * ! * @return Reader for reading the print data characters from this doc. ! * If a reader cannot be provided because this doc does not meet ! * the criteria stated above, null is returned. * ! * @exception IOException ! * Thrown if there was an I/O error while creating the reader. */ public Reader getReaderForText() throws IOException; /** ! * Obtains an input stream for extracting byte print data from this ! * doc. The Doc implementation is required to support this method if ! * the DocFlavor has one of the following print data representation ! * classes, and return null otherwise: ! * <UL> ! * <LI> byte[] ! * <LI> java.io.InputStream ! * </UL> * This doc's print data representation object is obtained, then an input * stream for reading the print data from the print data representation * object as a stream of bytes is created and returned. However, if the * print data representation object is itself an input stream, then the * print data representation object is simply returned. * ! * @return Input stream for reading the print data bytes from this doc. If ! * an input stream cannot be provided because this doc does not ! * meet the criteria stated above, null is returned. ! * ! * @exception IOException ! * Thrown if there was an I/O error while creating the input stream. */ public InputStream getStreamForBytes() throws IOException; - } --- 23,189 ---- * questions. */ package javax.print; import java.io.IOException; + import java.io.InputStream; import java.io.Reader; import javax.print.attribute.DocAttributeSet; /** ! * Interface {@code Doc} specifies the interface for an object that supplies one ! * piece of print data for a Print Job. "Doc" is a short, easy-to-pronounce term * that means "a piece of print data." The client passes to the Print Job an ! * object that implements interface {@code Doc}, and the Print Job calls methods ! * on that object to obtain the print data. The {@code Doc} interface lets a ! * Print Job: ! * <ul> ! * <li>Determine the format, or "doc flavor" (class ! * {@link DocFlavor DocFlavor}), in which the print data is available. A doc ! * flavor designates the print data format (a MIME type) and the ! * representation class of the object from which the print data comes. ! * <li>Obtain the print data representation object, which is an instance of ! * the doc flavor's representation class. The Print Job can then obtain the ! * actual print data from the representation object. ! * <li>Obtain the printing attributes that specify additional characteristics ! * of the doc or that specify processing instructions to be applied to the ! * doc. Printing attributes are defined in package ! * {@link javax.print.attribute}. The doc returns its printing attributes ! * stored in an {@link DocAttributeSet javax.print.attribute.DocAttributeSet}. ! * </ul> ! * Each method in an implementation of interface {@code Doc} is permitted always ! * to return the same object each time the method is called. This has ! * implications for a Print Job or other caller of a doc object whose print data * representation object "consumes" the print data as the caller obtains the * print data, such as a print data representation object which is a stream. ! * Once the Print Job has called {@link #getPrintData() getPrintData()} and ! * obtained the stream, any further calls to {@link #getPrintData() ! * getPrintData()} will return the same stream object upon which reading may ! * already be in progress, <i>not</i> a new stream object that will re-read the ! * print data from the beginning. Specifying a doc object to behave this way ! * simplifies the implementation of doc objects, and is justified on the grounds ! * that a particular doc is intended to convey print data only to one Print Job, ! * not to several different Print Jobs. (To convey the same print data to ! * several different Print Jobs, you have to create several different doc ! * objects on top of the same print data source.) ! * <p> ! * Interface {@code Doc} affords considerable implementation flexibility. The ! * print data might already be in existence when the doc object is constructed. ! * In this case the objects returned by the doc's methods can be supplied to the ! * doc's constructor, be stored in the doc ahead of time, and simply be returned ! * when called for. Alternatively, the print data might not exist yet when the ! * doc object is constructed. In this case the doc object might provide a "lazy" * implementation that generates the print data representation object (and/or * the print data) only when the Print Job calls for it (when the Print Job * calls the {@link #getPrintData() getPrintData()} method). ! * <p> * There is no restriction on the number of client threads that may be * simultaneously accessing the same doc. Therefore, all implementations of ! * interface {@code Doc} must be designed to be multiple thread safe. * <p> * However there can only be one consumer of the print data obtained from a ! * {@code Doc}. * <p> ! * If print data is obtained from the client as a stream, by calling ! * {@code Doc}'s {@code getReaderForText()} or {@code getStreamForBytes()} ! * methods, or because the print data source is already an {@code InputStream} ! * or {@code Reader}, then the print service should always close these streams ! * for the client on all job completion conditions. With the following caveat. ! * If the print data is itself a stream, the service will always close it. If ! * the print data is otherwise something that can be requested as a stream, the ! * service will only close the stream if it has obtained the stream before ! * terminating. That is, just because a print service might request data as a ! * stream does not mean that it will, with the implications that {@code Doc} * implementors which rely on the service to close them should create such * streams only in response to a request from the service. */ public interface Doc { /** ! * Determines the doc flavor in which this doc object will supply its piece ! * of print data. * ! * @return doc flavor */ public DocFlavor getDocFlavor(); /** * Obtains the print data representation object that contains this doc ! * object's piece of print data in the format corresponding to the supported ! * doc flavor. The {@code getPrintData()} method returns an instance of the ! * representation class whose name is given by{@link #getDocFlavor() ! * getDocFlavor()}.{@link DocFlavor#getRepresentationClassName() ! * getRepresentationClassName()}, and the return value can be cast from ! * class {@code Object} to that representation class. ! * ! * @return print data representation object ! * @throws IOException if the representation class is a stream and there was ! * an I/O error while constructing the stream */ public Object getPrintData() throws IOException; /** * Obtains the set of printing attributes for this doc object. If the * returned attribute set includes an instance of a particular attribute ! * <i>X,</i> the printer must use that attribute value for this doc, ! * overriding any value of attribute <i>X</i> in the job's attribute set. If ! * the returned attribute set does not include an instance of a particular ! * attribute <i>X</i> or if {@code null} is returned, the printer must ! * consult the job's attribute set to obtain the value for attribute ! * <i>X,</i> and if not found there, the printer must use an * implementation-dependent default value. The returned attribute set is * unmodifiable. * ! * @return unmodifiable set of printing attributes for this doc, or ! * {@code null} to obtain all attribute values from the job's ! * attribute set */ public DocAttributeSet getAttributes(); /** ! * Obtains a reader for extracting character print data from this doc. The ! * {@code Doc} implementation is required to support this method if the ! * {@code DocFlavor} has one of the following print data representation ! * classes, and return {@code null} otherwise: ! * <ul> ! * <li>char[] ! * <li>java.lang.String ! * <li>java.io.Reader ! * </ul> * The doc's print data representation object is used to construct and ! * return a {@code Reader} for reading the print data as a stream of ! * characters from the print data representation object. However, if the ! * print data representation object is itself a {@code Reader}, then the ! * print data representation object is simply returned. * ! * @return reader for reading the print data characters from this doc. If a ! * reader cannot be provided because this doc does not meet the ! * criteria stated above, {@code null} is returned. ! * @throws IOException if there was an I/O error while creating the reader */ public Reader getReaderForText() throws IOException; /** ! * Obtains an input stream for extracting byte print data from this doc. The ! * {@code Doc} implementation is required to support this method if the ! * {@code DocFlavor} has one of the following print data representation ! * classes, and return {@code null} otherwise: ! * <ul> ! * <li>byte[] ! * <li>java.io.InputStream ! * </ul> * This doc's print data representation object is obtained, then an input * stream for reading the print data from the print data representation * object as a stream of bytes is created and returned. However, if the * print data representation object is itself an input stream, then the * print data representation object is simply returned. * ! * @return input stream for reading the print data bytes from this doc. If ! * an input stream cannot be provided because this doc does not meet ! * the criteria stated above, {@code null} is returned. ! * @throws IOException if there was an I/O error while creating the input ! * stream */ public InputStream getStreamForBytes() throws IOException; }
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