1. // XMLFilter.java - filter SAX2 events.

  2. // Written by David Megginson, sax@megginson.com

  3. // NO WARRANTY!  This class is in the Public Domain.

  4. 

  5. // $Id: XMLFilter.java,v 1.1 2001/05/20 03:12:56 curcuru Exp $

  6. 

  7. 

  8. package org.xml.sax;

  9. 

  10. 

  11. /**

  12.  * Interface for an XML filter.

  13.  *

  14.  * <blockquote>

  15.  * <em>This module, both source code and documentation, is in the

  16.  * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>

  17.  * </blockquote>

  18.  *

  19.  * <p>An XML filter is like an XML reader, except that it obtains its

  20.  * events from another XML reader rather than a primary source like

  21.  * an XML document or database.  Filters can modify a stream of

  22.  * events as they pass on to the final application.</p>

  23.  *

  24.  * <p>The XMLFilterImpl helper class provides a convenient base

  25.  * for creating SAX2 filters, by passing on all {@link org.xml.sax.EntityResolver

  26.  * EntityResolver}, {@link org.xml.sax.DTDHandler DTDHandler},

  27.  * {@link org.xml.sax.ContentHandler ContentHandler} and {@link org.xml.sax.ErrorHandler

  28.  * ErrorHandler} events automatically.</p>

  29.  *

  30.  * @since SAX 2.0

  31.  * @author David Megginson, 

  32.  *         <a href="mailto:sax@megginson.com">sax@megginson.com</a>

  33.  * @version 2.0r2pre

  34.  * @see org.xml.sax.helpers.XMLFilterImpl

  35.  */

  36. public interface XMLFilter extends XMLReader

  37. {

  38. 

  39.     /**

  40.      * Set the parent reader.

  41.      *

  42.      * <p>This method allows the application to link the filter to

  43.      * a parent reader (which may be another filter).  The argument

  44.      * may not be null.</p>

  45.      *

  46.      * @param parent The parent reader.

  47.      */

  48.     public abstract void setParent (XMLReader parent);

  49. 

  50. 

  51.     /**

  52.      * Get the parent reader.

  53.      *

  54.      * <p>This method allows the application to query the parent

  55.      * reader (which may be another filter).  It is generally a

  56.      * bad idea to perform any operations on the parent reader

  57.      * directly: they should all pass through this filter.</p>

  58.      *

  59.      * @return The parent filter, or null if none has been set.

  60.      */

  61.     public abstract XMLReader getParent ();

  62. 

  63. }

  64. 

  65. // end of XMLFilter.java