jaxp/src/org/xml/sax/XMLReader.java
changeset 12457 c348e06f0e82
parent 12005 a754d69d5e60
child 25262 1fe892ba017a
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jaxp/src/org/xml/sax/XMLReader.java	Thu Apr 12 08:38:26 2012 -0700
@@ -0,0 +1,428 @@
+/*
+ * Copyright (c) 2000, 2005, 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
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+// XMLReader.java - read an XML document.
+// http://www.saxproject.org
+// Written by David Megginson
+// NO WARRANTY!  This class is in the Public Domain.
+// $Id: XMLReader.java,v 1.3 2004/11/03 22:55:32 jsuttor Exp $
+
+package org.xml.sax;
+
+import java.io.IOException;
+
+
+/**
+ * Interface for reading an XML document using callbacks.
+ *
+ * <blockquote>
+ * <em>This module, both source code and documentation, is in the
+ * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>
+ * See <a href='http://www.saxproject.org'>http://www.saxproject.org</a>
+ * for further information.
+ * </blockquote>
+ *
+ * <p><strong>Note:</strong> despite its name, this interface does
+ * <em>not</em> extend the standard Java {@link java.io.Reader Reader}
+ * interface, because reading XML is a fundamentally different activity
+ * than reading character data.</p>
+ *
+ * <p>XMLReader is the interface that an XML parser's SAX2 driver must
+ * implement.  This interface allows an application to set and
+ * query features and properties in the parser, to register
+ * event handlers for document processing, and to initiate
+ * a document parse.</p>
+ *
+ * <p>All SAX interfaces are assumed to be synchronous: the
+ * {@link #parse parse} methods must not return until parsing
+ * is complete, and readers must wait for an event-handler callback
+ * to return before reporting the next event.</p>
+ *
+ * <p>This interface replaces the (now deprecated) SAX 1.0 {@link
+ * org.xml.sax.Parser Parser} interface.  The XMLReader interface
+ * contains two important enhancements over the old Parser
+ * interface (as well as some minor ones):</p>
+ *
+ * <ol>
+ * <li>it adds a standard way to query and set features and
+ *  properties; and</li>
+ * <li>it adds Namespace support, which is required for many
+ *  higher-level XML standards.</li>
+ * </ol>
+ *
+ * <p>There are adapters available to convert a SAX1 Parser to
+ * a SAX2 XMLReader and vice-versa.</p>
+ *
+ * @since SAX 2.0
+ * @author David Megginson
+ * @see org.xml.sax.XMLFilter
+ * @see org.xml.sax.helpers.ParserAdapter
+ * @see org.xml.sax.helpers.XMLReaderAdapter
+ */
+public interface XMLReader
+{
+
+
+    ////////////////////////////////////////////////////////////////////
+    // Configuration.
+    ////////////////////////////////////////////////////////////////////
+
+
+    /**
+     * Look up the value of a feature flag.
+     *
+     * <p>The feature name is any fully-qualified URI.  It is
+     * possible for an XMLReader to recognize a feature name but
+     * temporarily be unable to return its value.
+     * Some feature values may be available only in specific
+     * contexts, such as before, during, or after a parse.
+     * Also, some feature values may not be programmatically accessible.
+     * (In the case of an adapter for SAX1 {@link Parser}, there is no
+     * implementation-independent way to expose whether the underlying
+     * parser is performing validation, expanding external entities,
+     * and so forth.) </p>
+     *
+     * <p>All XMLReaders are required to recognize the
+     * http://xml.org/sax/features/namespaces and the
+     * http://xml.org/sax/features/namespace-prefixes feature names.</p>
+     *
+     * <p>Typical usage is something like this:</p>
+     *
+     * <pre>
+     * XMLReader r = new MySAXDriver();
+     *
+     *                         // try to activate validation
+     * try {
+     *   r.setFeature("http://xml.org/sax/features/validation", true);
+     * } catch (SAXException e) {
+     *   System.err.println("Cannot activate validation.");
+     * }
+     *
+     *                         // register event handlers
+     * r.setContentHandler(new MyContentHandler());
+     * r.setErrorHandler(new MyErrorHandler());
+     *
+     *                         // parse the first document
+     * try {
+     *   r.parse("http://www.foo.com/mydoc.xml");
+     * } catch (IOException e) {
+     *   System.err.println("I/O exception reading XML document");
+     * } catch (SAXException e) {
+     *   System.err.println("XML exception reading document.");
+     * }
+     * </pre>
+     *
+     * <p>Implementors are free (and encouraged) to invent their own features,
+     * using names built on their own URIs.</p>
+     *
+     * @param name The feature name, which is a fully-qualified URI.
+     * @return The current value of the feature (true or false).
+     * @exception org.xml.sax.SAXNotRecognizedException If the feature
+     *            value can't be assigned or retrieved.
+     * @exception org.xml.sax.SAXNotSupportedException When the
+     *            XMLReader recognizes the feature name but
+     *            cannot determine its value at this time.
+     * @see #setFeature
+     */
+    public boolean getFeature (String name)
+        throws SAXNotRecognizedException, SAXNotSupportedException;
+
+
+    /**
+     * Set the value of a feature flag.
+     *
+     * <p>The feature name is any fully-qualified URI.  It is
+     * possible for an XMLReader to expose a feature value but
+     * to be unable to change the current value.
+     * Some feature values may be immutable or mutable only
+     * in specific contexts, such as before, during, or after
+     * a parse.</p>
+     *
+     * <p>All XMLReaders are required to support setting
+     * http://xml.org/sax/features/namespaces to true and
+     * http://xml.org/sax/features/namespace-prefixes to false.</p>
+     *
+     * @param name The feature name, which is a fully-qualified URI.
+     * @param value The requested value of the feature (true or false).
+     * @exception org.xml.sax.SAXNotRecognizedException If the feature
+     *            value can't be assigned or retrieved.
+     * @exception org.xml.sax.SAXNotSupportedException When the
+     *            XMLReader recognizes the feature name but
+     *            cannot set the requested value.
+     * @see #getFeature
+     */
+    public void setFeature (String name, boolean value)
+        throws SAXNotRecognizedException, SAXNotSupportedException;
+
+
+    /**
+     * Look up the value of a property.
+     *
+     * <p>The property name is any fully-qualified URI.  It is
+     * possible for an XMLReader to recognize a property name but
+     * temporarily be unable to return its value.
+     * Some property values may be available only in specific
+     * contexts, such as before, during, or after a parse.</p>
+     *
+     * <p>XMLReaders are not required to recognize any specific
+     * property names, though an initial core set is documented for
+     * SAX2.</p>
+     *
+     * <p>Implementors are free (and encouraged) to invent their own properties,
+     * using names built on their own URIs.</p>
+     *
+     * @param name The property name, which is a fully-qualified URI.
+     * @return The current value of the property.
+     * @exception org.xml.sax.SAXNotRecognizedException If the property
+     *            value can't be assigned or retrieved.
+     * @exception org.xml.sax.SAXNotSupportedException When the
+     *            XMLReader recognizes the property name but
+     *            cannot determine its value at this time.
+     * @see #setProperty
+     */
+    public Object getProperty (String name)
+        throws SAXNotRecognizedException, SAXNotSupportedException;
+
+
+    /**
+     * Set the value of a property.
+     *
+     * <p>The property name is any fully-qualified URI.  It is
+     * possible for an XMLReader to recognize a property name but
+     * to be unable to change the current value.
+     * Some property values may be immutable or mutable only
+     * in specific contexts, such as before, during, or after
+     * a parse.</p>
+     *
+     * <p>XMLReaders are not required to recognize setting
+     * any specific property names, though a core set is defined by
+     * SAX2.</p>
+     *
+     * <p>This method is also the standard mechanism for setting
+     * extended handlers.</p>
+     *
+     * @param name The property name, which is a fully-qualified URI.
+     * @param value The requested value for the property.
+     * @exception org.xml.sax.SAXNotRecognizedException If the property
+     *            value can't be assigned or retrieved.
+     * @exception org.xml.sax.SAXNotSupportedException When the
+     *            XMLReader recognizes the property name but
+     *            cannot set the requested value.
+     */
+    public void setProperty (String name, Object value)
+        throws SAXNotRecognizedException, SAXNotSupportedException;
+
+
+
+    ////////////////////////////////////////////////////////////////////
+    // Event handlers.
+    ////////////////////////////////////////////////////////////////////
+
+
+    /**
+     * Allow an application to register an entity resolver.
+     *
+     * <p>If the application does not register an entity resolver,
+     * the XMLReader will perform its own default resolution.</p>
+     *
+     * <p>Applications may register a new or different resolver in the
+     * middle of a parse, and the SAX parser must begin using the new
+     * resolver immediately.</p>
+     *
+     * @param resolver The entity resolver.
+     * @see #getEntityResolver
+     */
+    public void setEntityResolver (EntityResolver resolver);
+
+
+    /**
+     * Return the current entity resolver.
+     *
+     * @return The current entity resolver, or null if none
+     *         has been registered.
+     * @see #setEntityResolver
+     */
+    public EntityResolver getEntityResolver ();
+
+
+    /**
+     * Allow an application to register a DTD event handler.
+     *
+     * <p>If the application does not register a DTD handler, all DTD
+     * events reported by the SAX parser will be silently ignored.</p>
+     *
+     * <p>Applications may register a new or different handler in the
+     * middle of a parse, and the SAX parser must begin using the new
+     * handler immediately.</p>
+     *
+     * @param handler The DTD handler.
+     * @see #getDTDHandler
+     */
+    public void setDTDHandler (DTDHandler handler);
+
+
+    /**
+     * Return the current DTD handler.
+     *
+     * @return The current DTD handler, or null if none
+     *         has been registered.
+     * @see #setDTDHandler
+     */
+    public DTDHandler getDTDHandler ();
+
+
+    /**
+     * Allow an application to register a content event handler.
+     *
+     * <p>If the application does not register a content handler, all
+     * content events reported by the SAX parser will be silently
+     * ignored.</p>
+     *
+     * <p>Applications may register a new or different handler in the
+     * middle of a parse, and the SAX parser must begin using the new
+     * handler immediately.</p>
+     *
+     * @param handler The content handler.
+     * @see #getContentHandler
+     */
+    public void setContentHandler (ContentHandler handler);
+
+
+    /**
+     * Return the current content handler.
+     *
+     * @return The current content handler, or null if none
+     *         has been registered.
+     * @see #setContentHandler
+     */
+    public ContentHandler getContentHandler ();
+
+
+    /**
+     * Allow an application to register an error event handler.
+     *
+     * <p>If the application does not register an error handler, all
+     * error events reported by the SAX parser will be silently
+     * ignored; however, normal processing may not continue.  It is
+     * highly recommended that all SAX applications implement an
+     * error handler to avoid unexpected bugs.</p>
+     *
+     * <p>Applications may register a new or different handler in the
+     * middle of a parse, and the SAX parser must begin using the new
+     * handler immediately.</p>
+     *
+     * @param handler The error handler.
+     * @see #getErrorHandler
+     */
+    public void setErrorHandler (ErrorHandler handler);
+
+
+    /**
+     * Return the current error handler.
+     *
+     * @return The current error handler, or null if none
+     *         has been registered.
+     * @see #setErrorHandler
+     */
+    public ErrorHandler getErrorHandler ();
+
+
+
+    ////////////////////////////////////////////////////////////////////
+    // Parsing.
+    ////////////////////////////////////////////////////////////////////
+
+    /**
+     * Parse an XML document.
+     *
+     * <p>The application can use this method to instruct the XML
+     * reader to begin parsing an XML document from any valid input
+     * source (a character stream, a byte stream, or a URI).</p>
+     *
+     * <p>Applications may not invoke this method while a parse is in
+     * progress (they should create a new XMLReader instead for each
+     * nested XML document).  Once a parse is complete, an
+     * application may reuse the same XMLReader object, possibly with a
+     * different input source.
+     * Configuration of the XMLReader object (such as handler bindings and
+     * values established for feature flags and properties) is unchanged
+     * by completion of a parse, unless the definition of that aspect of
+     * the configuration explicitly specifies other behavior.
+     * (For example, feature flags or properties exposing
+     * characteristics of the document being parsed.)
+     * </p>
+     *
+     * <p>During the parse, the XMLReader will provide information
+     * about the XML document through the registered event
+     * handlers.</p>
+     *
+     * <p>This method is synchronous: it will not return until parsing
+     * has ended.  If a client application wants to terminate
+     * parsing early, it should throw an exception.</p>
+     *
+     * @param input The input source for the top-level of the
+     *        XML document.
+     * @exception org.xml.sax.SAXException Any SAX exception, possibly
+     *            wrapping another exception.
+     * @exception java.io.IOException An IO exception from the parser,
+     *            possibly from a byte stream or character stream
+     *            supplied by the application.
+     * @see org.xml.sax.InputSource
+     * @see #parse(java.lang.String)
+     * @see #setEntityResolver
+     * @see #setDTDHandler
+     * @see #setContentHandler
+     * @see #setErrorHandler
+     */
+    public void parse (InputSource input)
+        throws IOException, SAXException;
+
+
+    /**
+     * Parse an XML document from a system identifier (URI).
+     *
+     * <p>This method is a shortcut for the common case of reading a
+     * document from a system identifier.  It is the exact
+     * equivalent of the following:</p>
+     *
+     * <pre>
+     * parse(new InputSource(systemId));
+     * </pre>
+     *
+     * <p>If the system identifier is a URL, it must be fully resolved
+     * by the application before it is passed to the parser.</p>
+     *
+     * @param systemId The system identifier (URI).
+     * @exception org.xml.sax.SAXException Any SAX exception, possibly
+     *            wrapping another exception.
+     * @exception java.io.IOException An IO exception from the parser,
+     *            possibly from a byte stream or character stream
+     *            supplied by the application.
+     * @see #parse(org.xml.sax.InputSource)
+     */
+    public void parse (String systemId)
+        throws IOException, SAXException;
+
+}