//==============================================================================
// DocumentFilterI.java
//==============================================================================

package tribble.search;


// System imports

import java.lang.String;


// Local imports

// (None)


/*******************************************************************************
* Generic document entry filter.
*
* <p>
* Implementations of this interface are used to selectively filter document
* entries as they are being searched for by document searchers.  (Document
* searchers are implementations of the {@link DocumentSearcherI} interface.)
*
* <p>
* It is recommended that classes that implement this interface provide two
* kinds of constructors:
* <pre>
*    class <b>MyFilter</b>
*        implements tribble.search.DocumentFilterI
*    {
*        // Default constructor
*        public <b>MyFilter</b>()
*        { ... }
*
*        // Constructor
*        public <b>MyFilter</b>(String pred)
*        { ... }
*
*        ...
*    } </pre>
*
* <p>
* The second constructor takes an argument, <tt>pred</tt>, which is a string
* containing some sort of conditional expression (e.g., like an SQL
* <tt>SELECT</tt> statement) that specifies the filtering criteria.
*
* <p>
* This interface was modelled after the {@link java.io.FilenameFilter}
* interface.
*
* @version	$Revision: 1.3 $ $Date: 2001/06/18 03:07:13 $
* @since	2001-05-18
* @author
*	David R. Tribble
*	(<a href="mailto:david@tribble.com">david@tribble.com</a>).
*	<br>
*	<a href="../Copyright.html">Copyright</a>
*	©2001 by David R. Tribble, all rights reserved. <br>
*
* @see	DocumentSearcherI
* @see	DocumentI
*/

public interface DocumentFilterI
{
// Identification

    /** Revision information. */
    static final String		REV =
        "@(#)tribble/search/DocumentFilterI.java $Revision: 1.3 $ $Date: 2001/06/18 03:07:13 $\n";


// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// Public constants

    /** Series number. */
    public static final int	SERIES =	200;


// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// Public methods

    /***************************************************************************
    * Accept or reject a document entry.
    *
    * @param	doc
    * A document entry.
    *
    * @return
    * True if document entry <tt>doc</tt> is to be accepted, otherwise false if
    * it is to be rejected.
    *
    * @throws	Exception
    * Thrown if the selection criteria are malformed, or if some other error
    * occurs.
    *
    * @since	1.2, 2001-06-15
    *
    * @see	DocumentSearcherI#find
    */

    public boolean accept(DocumentI doc)
        throws Exception;
}

// End DocumentFilterI.java