// LexicalHandler.java - optional handler for lexical parse events.
// http://www.saxproject.org
// Public Domain: no warranty.
// $Id: LexicalHandler.java,v 1.5 2002/01/30 21:00:44 dbrownell Exp $
package org.xml.sax.ext;
import org.xml.sax.SAXException;
/**
* SAX2 extension handler for lexical 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>This is an optional extension handler for SAX2 to provide
* lexical information about an XML document, such as comments
* and CDATA section boundaries.
* XML readers are not required to recognize this handler, and it
* is not part of core-only SAX2 distributions.</p>
*
* <p>The events in the lexical handler apply to the entire document,
* not just to the document element, and all lexical handler events
* must appear between the content handler's startDocument and
* endDocument events.</p>
*
* <p>To set the LexicalHandler for an XML reader, use the
* {@link org.xml.sax.XMLReader#setProperty setProperty} method
* with the property name
* <code>http://xml.org/sax/properties/lexical-handler</code>
* and an object implementing this interface (or null) as the value.
* If the reader does not report lexical events, it will throw a
* {@link org.xml.sax.SAXNotRecognizedException SAXNotRecognizedException}
* when you attempt to register the handler.</p>
*
* @since SAX 2.0 (extensions 1.0)
* @author David Megginson
* @version 2.0.1 (sax2r2)
*/
public interface LexicalHandler
{
/**
* Report the start of DTD declarations, if any.
*
* <p>This method is intended to report the beginning of the
* DOCTYPE declaration; if the document has no DOCTYPE declaration,
* this method will not be invoked.</p>
*
* <p>All declarations reported through
* {@link org.xml.sax.DTDHandler DTDHandler} or
* {@link org.xml.sax.ext.DeclHandler DeclHandler} events must appear
* between the startDTD and {@link #endDTD endDTD} events.
* Declarations are assumed to belong to the internal DTD subset
* unless they appear between {@link #startEntity startEntity}
* and {@link #endEntity endEntity} events. Comments and
* processing instructions from the DTD should also be reported
* between the startDTD and endDTD events, in their original
* order of (logical) occurrence; they are not required to
* appear in their correct locations relative to DTDHandler
* or DeclHandler events, however.</p>
*
* <p>Note that the start/endDTD events will appear within
* the start/endDocument events from ContentHandler and
* before the first
* {@link org.xml.sax.ContentHandler#startElement startElement}
* event.</p>
*
* @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.)
* @exception SAXException The application may raise an
* exception.
* @see #endDTD
* @see #startEntity
*/
public abstract void startDTD (String name, String publicId,
String systemId)
throws SAXException;
/**
* Report the end of DTD declarations.
*
* <p>This method is intended to report the end of the
* DOCTYPE declaration; if the document has no DOCTYPE declaration,
* this method will not be invoked.</p>
*
* @exception SAXException The application may raise an exception.
* @see #startDTD
*/
public abstract void endDTD ()
throws SAXException;
/**
* Report the beginning of some internal and external XML entities.
*
* <p>The reporting of parameter entities (including
* the external DTD subset) is optional, and SAX2 drivers that
* report LexicalHandler events may not implement it; you can use the
* <code
* >http://xml.org/sax/features/lexical-handler/parameter-entities</code>
* feature to query or control the reporting of parameter entities.</p>
*
* <p>General entities are reported with their regular names,
* parameter entities have '%' prepended to their names, and
* the external DTD subset has the pseudo-entity name "[dtd]".</p>
*
* <p>When a SAX2 driver is providing these events, all other
* events must be properly nested within start/end entity
* events. There is no additional requirement that events from
* {@link org.xml.sax.ext.DeclHandler DeclHandler} or
* {@link org.xml.sax.DTDHandler DTDHandler} be properly ordered.</p>
*
* <p>Note that skipped entities will be reported through the
* {@link org.xml.sax.ContentHandler#skippedEntity skippedEntity}
* event, which is part of the ContentHandler interface.</p>
*
* <p>Because of the streaming event model that SAX uses, some
* entity boundaries cannot be reported under any
* circumstances:</p>
*
* <ul>
* <li>general entities within attribute values</li>
* <li>parameter entities within declarations</li>
* </ul>
*
* <p>These will be silently expanded, with no indication of where
* the original entity boundaries were.</p>
*
* <p>Note also that the boundaries of character references (which
* are not really entities anyway) are not reported.</p>
*
* <p>All start/endEntity events must be properly nested.
*
* @param name The name of the entity. If it is a parameter
* entity, the name will begin with '%', and if it is the
* external DTD subset, it will be "[dtd]".
* @exception SAXException The application may raise an exception.
* @see #endEntity
* @see org.xml.sax.ext.DeclHandler#internalEntityDecl
* @see org.xml.sax.ext.DeclHandler#externalEntityDecl
*/
public abstract void startEntity (String name)
throws SAXException;
/**
* Report the end of an entity.
*
* @param name The name of the entity that is ending.
* @exception SAXException The application may raise an exception.
* @see #startEntity
*/
public abstract void endEntity (String name)
throws SAXException;
/**
* Report the start of a CDATA section.
*
* <p>The contents of the CDATA section will be reported through
* the regular {@link org.xml.sax.ContentHandler#characters
* characters} event; this event is intended only to report
* the boundary.</p>
*
* @exception SAXException The application may raise an exception.
* @see #endCDATA
*/
public abstract void startCDATA ()
throws SAXException;
/**
* Report the end of a CDATA section.
*
* @exception SAXException The application may raise an exception.
* @see #startCDATA
*/
public abstract void endCDATA ()
throws SAXException;
/**
* Report an XML comment anywhere in the document.
*
* <p>This callback will be used for comments inside or outside the
* document element, including comments in the external DTD
* subset (if read). Comments in the DTD must be properly
* nested inside start/endDTD and start/endEntity events (if
* used).</p>
*
* @param ch An array holding the characters in the comment.
* @param start The starting position in the array.
* @param length The number of characters to use from the array.
* @exception SAXException The application may raise an exception.
*/
public abstract void comment (char ch[], int start, int length)
throws SAXException;
}
// end of LexicalHandler.java