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	/*
	* 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.
	*/

	// ContentHandler.java - handle main document content.
	// http://www.saxproject.org
	// Written by David Megginson
	// NO WARRANTY! This class is in the public domain.
	// $Id: ContentHandler.java,v 1.2 2004/11/03 22:44:51 jsuttor Exp $

	package org.xml.sax;


	/**
	* Receive notification of the logical content of a document.
	*
	* <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>This is the main interface that most SAX applications
	* implement: if the application needs to be informed of basic parsing
	* events, it implements this interface and registers an instance with
	* the SAX parser using the {@link org.xml.sax.XMLReader#setContentHandler
	* setContentHandler} method. The parser uses the instance to report
	* basic document-related events like the start and end of elements
	* and character data.</p>
	*
	* <p>The order of events in this interface is very important, and
	* mirrors the order of information in the document itself. For
	* example, all of an element's content (character data, processing
	* instructions, and/or subelements) will appear, in order, between
	* the startElement event and the corresponding endElement event.</p>
	*
	* <p>This interface is similar to the now-deprecated SAX 1.0
	* DocumentHandler interface, but it adds support for Namespaces
	* and for reporting skipped entities (in non-validating XML
	* processors).</p>
	*
	* <p>Implementors should note that there is also a
	* <code>ContentHandler</code> class in the <code>java.net</code>
	* package; that means that it's probably a bad idea to do</p>
	*
	* <pre>import java.net.*;
	* import org.xml.sax.*;
	* </pre>
	*
	* <p>In fact, "import ...*" is usually a sign of sloppy programming
	* anyway, so the user should consider this a feature rather than a
	* bug.</p>
	*
	* @since 1.4, SAX 2.0
	* @author David Megginson
	* @see org.xml.sax.XMLReader
	* @see org.xml.sax.DTDHandler
	* @see org.xml.sax.ErrorHandler
	*/
	public interface ContentHandler
	{

	/**
	* Receive an object for locating the origin of SAX document events.
	*
	* <p>SAX parsers are strongly encouraged (though not absolutely
	* required) to supply a locator: if it does so, it must supply
	* the locator to the application by invoking this method before
	* invoking any of the other methods in the ContentHandler
	* interface.</p>
	*
	* <p>The locator allows the application to determine the end
	* position of any document-related event, even if the parser is
	* not reporting an error. Typically, the application will
	* use this information for reporting its own errors (such as
	* character content that does not match an application's
	* business rules). The information returned by the locator
	* is probably not sufficient for use with a search engine.</p>
	*
	* <p>Note that the locator will return correct information only
	* during the invocation SAX event callbacks after
	* {@link #startDocument startDocument} returns and before
	* {@link #endDocument endDocument} is called. The
	* application should not attempt to use it at any other time.</p>
	*
	* @param locator an object that can return the location of
	* any SAX document event
	* @see org.xml.sax.Locator
	*/
	public void setDocumentLocator (Locator locator);


	/**
	* Receive notification of the beginning of a document.
	*
	* <p>The SAX parser will invoke this method only once, before any
	* other event callbacks (except for {@link #setDocumentLocator
	* setDocumentLocator}).</p>
	*
	* @throws org.xml.sax.SAXException any SAX exception, possibly
	* wrapping another exception
	* @see #endDocument
	*/
	public void startDocument ()
	throws SAXException;


	/**
	* Receive notification of the end of a document.
	*
	* <p><strong>There is an apparent contradiction between the
	* documentation for this method and the documentation for {@link
	* org.xml.sax.ErrorHandler#fatalError}. Until this ambiguity is
	* resolved in a future major release, clients should make no
	* assumptions about whether endDocument() will or will not be
	* invoked when the parser has reported a fatalError() or thrown
	* an exception.</strong></p>
	*
	* <p>The SAX parser will invoke this method only once, and it will
	* be the last method invoked during the parse. The parser shall
	* not invoke this method until it has either abandoned parsing
	* (because of an unrecoverable error) or reached the end of
	* input.</p>
	*
	* @throws org.xml.sax.SAXException any SAX exception, possibly
	* wrapping another exception
	* @see #startDocument
	*/
	public void endDocument()
	throws SAXException;


	/**
	* Begin the scope of a prefix-URI Namespace mapping.
	*
	* <p>The information from this event is not necessary for
	* normal Namespace processing: the SAX XML reader will
	* automatically replace prefixes for element and attribute
	* names when the <code>http://xml.org/sax/features/namespaces</code>
	* feature is <var>true</var> (the default).</p>
	*
	* <p>There are cases, however, when applications need to
	* use prefixes in character data or in attribute values,
	* where they cannot safely be expanded automatically; the
	* start/endPrefixMapping event supplies the information
	* to the application to expand prefixes in those contexts
	* itself, if necessary.</p>
	*
	* <p>Note that start/endPrefixMapping events are not
	* guaranteed to be properly nested relative to each other:
	* all startPrefixMapping events will occur immediately before the
	* corresponding {@link #startElement startElement} event,
	* and all {@link #endPrefixMapping endPrefixMapping}
	* events will occur immediately after the corresponding
	* {@link #endElement endElement} event,
	* but their order is not otherwise
	* guaranteed.</p>
	*
	* <p>There should never be start/endPrefixMapping events for the
	* "xml" prefix, since it is predeclared and immutable.</p>
	*
	* @param prefix the Namespace prefix being declared.
	* An empty string is used for the default element namespace,
	* which has no prefix.
	* @param uri the Namespace URI the prefix is mapped to
	* @throws org.xml.sax.SAXException the client may throw
	* an exception during processing
	* @see #endPrefixMapping
	* @see #startElement
	*/
	public void startPrefixMapping (String prefix, String uri)
	throws SAXException;


	/**
	* End the scope of a prefix-URI mapping.
	*
	* <p>See {@link #startPrefixMapping startPrefixMapping} for
	* details. These events will always occur immediately after the
	* corresponding {@link #endElement endElement} event, but the order of
	* {@link #endPrefixMapping endPrefixMapping} events is not otherwise
	* guaranteed.</p>
	*
	* @param prefix the prefix that was being mapped.
	* This is the empty string when a default mapping scope ends.
	* @throws org.xml.sax.SAXException the client may throw
	* an exception during processing
	* @see #startPrefixMapping
	* @see #endElement
	*/
	public void endPrefixMapping (String prefix)
	throws SAXException;


	/**
	* Receive notification of the beginning of an element.
	*
	* <p>The Parser will invoke this method at the beginning of every
	* element in the XML document; there will be a corresponding
	* {@link #endElement endElement} event for every startElement event
	* (even when the element is empty). All of the element's content will be
	* reported, in order, before the corresponding endElement
	* event.</p>
	*
	* <p>This event allows up to three name components for each
	* element:</p>
	*
	* <ol>
	* <li>the Namespace URI;</li>
	* <li>the local name; and</li>
	* <li>the qualified (prefixed) name.</li>
	* </ol>
	*
	* <p>Any or all of these may be provided, depending on the
	* values of the <var>http://xml.org/sax/features/namespaces</var>
	* and the <var>http://xml.org/sax/features/namespace-prefixes</var>
	* properties:</p>
	*
	* <ul>
	* <li>the Namespace URI and local name are required when
	* the namespaces property is <var>true</var> (the default), and are
	* optional when the namespaces property is <var>false</var> (if one is
	* specified, both must be);</li>
	* <li>the qualified name is required when the namespace-prefixes property
	* is <var>true</var>, and is optional when the namespace-prefixes property
	* is <var>false</var> (the default).</li>
	* </ul>
	*
	* <p>Note that the attribute list provided will contain only
	* attributes with explicit values (specified or defaulted):
	* #IMPLIED attributes will be omitted. The attribute list
	* will contain attributes used for Namespace declarations
	* (xmlns* attributes) only if the
	* <code>http://xml.org/sax/features/namespace-prefixes</code>
	* property is true (it is false by default, and support for a
	* true value is optional).</p>
	*
	* <p>Like {@link #characters characters()}, attribute values may have
	* characters that need more than one <code>char</code> value. </p>
	*
	* @param uri the Namespace URI, or the empty string if the
	* element has no Namespace URI or if Namespace
	* processing is not being performed
	* @param localName the local name (without prefix), or the
	* empty string if Namespace processing is not being
	* performed
	* @param qName the qualified name (with prefix), or the
	* empty string if qualified names are not available
	* @param atts the attributes attached to the element. If
	* there are no attributes, it shall be an empty
	* Attributes object. The value of this object after
	* startElement returns is undefined
	* @throws org.xml.sax.SAXException any SAX exception, possibly
	* wrapping another exception
	* @see #endElement
	* @see org.xml.sax.Attributes
	* @see org.xml.sax.helpers.AttributesImpl
	*/
	public void startElement (String uri, String localName,
	String qName, Attributes atts)
	throws SAXException;


	/**
	* Receive notification of the end of an element.
	*
	* <p>The SAX parser will invoke this method at the end of every
	* element in the XML document; there will be a corresponding
	* {@link #startElement startElement} event for every endElement
	* event (even when the element is empty).</p>
	*
	* <p>For information on the names, see startElement.</p>
	*
	* @param uri the Namespace URI, or the empty string if the
	* element has no Namespace URI or if Namespace
	* processing is not being performed
	* @param localName the local name (without prefix), or the
	* empty string if Namespace processing is not being
	* performed
	* @param qName the qualified XML name (with prefix), or the
	* empty string if qualified names are not available
	* @throws org.xml.sax.SAXException any SAX exception, possibly
	* wrapping another exception
	*/
	public void endElement (String uri, String localName,
	String qName)
	throws SAXException;


	/**
	* Receive notification of character data.
	*
	* <p>The Parser will call this method to report each chunk of
	* character data. SAX parsers may return all contiguous character
	* data in a single chunk, or they may split it into several
	* chunks; however, all of the characters in any single event
	* must come from the same external entity so that the Locator
	* provides useful information.</p>
	*
	* <p>The application must not attempt to read from the array
	* outside of the specified range.</p>
	*
	* <p>Individual characters may consist of more than one Java
	* <code>char</code> value. There are two important cases where this
	* happens, because characters can't be represented in just sixteen bits.
	* In one case, characters are represented in a <em>Surrogate Pair</em>,
	* using two special Unicode values. Such characters are in the so-called
	* "Astral Planes", with a code point above U+FFFF. A second case involves
	* composite characters, such as a base character combining with one or
	* more accent characters. </p>
	*
	* <p> Your code should not assume that algorithms using
	* <code>char</code>-at-a-time idioms will be working in character
	* units; in some cases they will split characters. This is relevant
	* wherever XML permits arbitrary characters, such as attribute values,
	* processing instruction data, and comments as well as in data reported
	* from this method. It's also generally relevant whenever Java code
	* manipulates internationalized text; the issue isn't unique to XML.</p>
	*
	* <p>Note that some parsers will report whitespace in element
	* content using the {@link #ignorableWhitespace ignorableWhitespace}
	* method rather than this one (validating parsers <em>must</em>
	* do so).</p>
	*
	* @param ch the characters from the XML document
	* @param start the start position in the array
	* @param length the number of characters to read from the array
	* @throws org.xml.sax.SAXException any SAX exception, possibly
	* wrapping another exception
	* @see #ignorableWhitespace
	* @see org.xml.sax.Locator
	*/
	public void characters (char ch[], int start, int length)
	throws SAXException;


	/**
	* Receive notification of ignorable whitespace in element content.
	*
	* <p>Validating Parsers must use this method to report each chunk
	* of whitespace in element content (see the W3C XML 1.0
	* recommendation, section 2.10): non-validating parsers may also
	* use this method if they are capable of parsing and using
	* content models.</p>
	*
	* <p>SAX parsers may return all contiguous whitespace in a single
	* chunk, or they may split it into several chunks; however, all of
	* the characters in any single event must come from the same
	* external entity, so that the Locator provides useful
	* information.</p>
	*
	* <p>The application must not attempt to read from the array
	* outside of the specified range.</p>
	*
	* @param ch the characters from the XML document
	* @param start the start position in the array
	* @param length the number of characters to read from the array
	* @throws org.xml.sax.SAXException any SAX exception, possibly
	* wrapping another exception
	* @see #characters
	*/
	public void ignorableWhitespace (char ch[], int start, int length)
	throws SAXException;


	/**
	* Receive notification of a processing instruction.
	*
	* <p>The Parser will invoke this method once for each processing
	* instruction found: note that processing instructions may occur
	* before or after the main document element.</p>
	*
	* <p>A SAX parser must never report an XML declaration (XML 1.0,
	* section 2.8) or a text declaration (XML 1.0, section 4.3.1)
	* using this method.</p>
	*
	* <p>Like {@link #characters characters()}, processing instruction
	* data may have characters that need more than one <code>char</code>
	* value. </p>
	*
	* @param target the processing instruction target
	* @param data the processing instruction data, or null if
	* none was supplied. The data does not include any
	* whitespace separating it from the target
	* @throws org.xml.sax.SAXException any SAX exception, possibly
	* wrapping another exception
	*/
	public void processingInstruction (String target, String data)
	throws SAXException;


	/**
	* Receive notification of a skipped entity.
	* This is not called for entity references within markup constructs
	* such as element start tags or markup declarations. (The XML
	* recommendation requires reporting skipped external entities.
	* SAX also reports internal entity expansion/non-expansion, except
	* within markup constructs.)
	*
	* <p>The Parser will invoke this method each time the entity is
	* skipped. Non-validating processors may skip entities if they
	* have not seen the declarations (because, for example, the
	* entity was declared in an external DTD subset). All processors
	* may skip external entities, depending on the values of the
	* <code>http://xml.org/sax/features/external-general-entities</code>
	* and the
	* <code>http://xml.org/sax/features/external-parameter-entities</code>
	* properties.</p>
	*
	* @param name the name of the skipped entity. If it is a
	* parameter entity, the name will begin with '%', and if
	* it is the external DTD subset, it will be the string
	* "[dtd]"
	* @throws org.xml.sax.SAXException any SAX exception, possibly
	* wrapping another exception
	*/
	public void skippedEntity (String name)
	throws SAXException;
	}

	// end of ContentHandler.java

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