/*
 * Copyright (c) 2000, 2018, 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
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 */

// SAX DTD handler.
// http://www.saxproject.org
// No warranty; no copyright -- use this as you will.
// $Id: DTDHandler.java,v 1.2 2004/11/03 22:44:51 jsuttor Exp $

package jdk.internal.org.xml.sax;

/**
 * Receive notification of basic DTD-related events.
 *
 * <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>If a SAX application needs information about notations and
 * unparsed entities, then the application implements this
 * interface and registers an instance with the SAX parser using
 * the parser's setDTDHandler method.  The parser uses the
 * instance to report notation and unparsed entity declarations to
 * the application.</p>
 *
 * <p>Note that this interface includes only those DTD events that
 * the XML recommendation <em>requires</em> processors to report:
 * notation and unparsed entity declarations.</p>
 *
 * <p>The SAX parser may report these events in any order, regardless
 * of the order in which the notations and unparsed entities were
 * declared; however, all DTD events must be reported after the
 * document handler's startDocument event, and before the first
 * startElement event.
 * (If the {@link org.xml.sax.ext.LexicalHandler LexicalHandler} is
 * used, these events must also be reported before the endDTD event.)
 * </p>
 *
 * <p>It is up to the application to store the information for
 * future use (perhaps in a hash table or object tree).
 * If the application encounters attributes of type "NOTATION",
 * "ENTITY", or "ENTITIES", it can use the information that it
 * obtained through this interface to find the entity and/or
 * notation corresponding with the attribute value.</p>
 *
 * @since SAX 1.0
 * @author David Megginson
 * @see org.xml.sax.XMLReader#setDTDHandler
 */
public interface DTDHandler {

    /**
     * Receive notification of a notation declaration event.
     *
     * <p>It is up to the application to record the notation for later
     * reference, if necessary;
     * notations may appear as attribute values and in unparsed entity
     * declarations, and are sometime used with processing instruction
     * target names.</p>
     *
     * <p>At least one of publicId and systemId must be non-null.
     * If a system identifier is present, and it is a URL, the SAX
     * parser must resolve it fully before passing it to the
     * application through this event.</p>
     *
     * <p>There is no guarantee that the notation declaration will be
     * reported before any unparsed entities that use it.</p>
     *
     * @param name The notation name.
     * @param publicId The notation's public identifier, or null if
     *        none was given.
     * @param systemId The notation's system identifier, or null if
     *        none was given.
     * @exception org.xml.sax.SAXException Any SAX exception, possibly
     *            wrapping another exception.
     * @see #unparsedEntityDecl
     * @see org.xml.sax.Attributes
     */
    public abstract void notationDecl (String name,
                                       String publicId,
                                       String systemId)
        throws SAXException;


    /**
     * Receive notification of an unparsed entity declaration event.
     *
     * <p>Note that the notation name corresponds to a notation
     * reported by the {@link #notationDecl notationDecl} event.
     * It is up to the application to record the entity for later
     * reference, if necessary;
     * unparsed entities may appear as attribute values.
     * </p>
     *
     * <p>If the system identifier is a URL, the parser must resolve it
     * fully before passing it to the application.</p>
     *
     * @exception org.xml.sax.SAXException Any SAX exception, possibly
     *            wrapping another exception.
     * @param name The unparsed entity's name.
     * @param publicId The entity's public identifier, or null if none
     *        was given.
     * @param systemId The entity's system identifier.
     * @param notationName The name of the associated notation.
     * @see #notationDecl
     * @see org.xml.sax.Attributes
     */
    public abstract void unparsedEntityDecl (String name,
                                             String publicId,
                                             String systemId,
                                             String notationName)
        throws SAXException;

    // from SAX2 extension DeclHandler
    /**
     * Receive notification of the start of DTD declarations.
     *
     * The start/endDTD events appear within the start/endDocument events
     * from ContentHandler.
     *
     * @param name The document type name.
     * @param publicId The declared public identifier for the
     *        external DTD subset, or null if none was declared.
     * @param systemId The declared system identifier for the
     *        external DTD subset, or null if none was declared.
     *        (Note that this is not resolved against the document
     *        base URI.)
     * @throws SAXException the event receiver may throw an exception during processing
     */
    default public void startDTD (String name, String publicId, String systemId)
        throws SAXException
    {
        // no op
    }

    // Custom API for the Properties

    /**
     * Receive notification of the start of DTD internal subset.
     *
     * @throws SAXException the event receiver may throw an exception during processing
     */
    default public void startInternalSub () throws SAXException
    {
        // no op
    }
}

// end of DTDHandler.java
