edu.ucsb.adl.middleware
Class DateRanker

java.lang.Object
  |
  +--edu.ucsb.adl.middleware.DateRanker

All Implemented Interfaces:

Ranker, XmlHandler

public final class DateRanker

extends java.lang.Object

implements Ranker, XmlHandler

Ranks query results by date. Dates are drawn from mappings to the adl:dates bucket; items lacking any such mappings are assigned a minimal rank.

Version:

$Header: /export/home/gjanee/middleware/edu/ucsb/adl/middleware/RCS/DateRanker.java,v 1.3 2004/09/05 21:48:13 gjanee Exp $

$Log: DateRanker.java,v $ Revision 1.3 2004/09/05 21:48:13 gjanee
Bug fix.

Revision 1.2 2003/06/10 04:14:51 gjanee
Almost total rewrite to conform to the new ADL bucket view and to the new Ranker interface, and to employ the new validating XML parser.

Revision 1.1 2000/03/01 05:32:27 gjanee
Initial revision

Author:

Greg Janée
Alexandria Digital Library

Method Summary

void	characters(char[] string, int start, int length) For use by ValidatingXmlParser only.
static edu.ucsb.adl.middleware.DateRanker	createRanker(java.lang.String order) Creates a DateRanker.
void	endElement(int elementCode) For use by ValidatingXmlParser only.
static void	main(java.lang.String[] args) Test driver.
double	rank(edu.ucsb.adl.middleware.Result result, edu.ucsb.adl.middleware.Query query) Ranks a query result.
void	startElement(int elementCode, java.lang.String[] attributes) For use by ValidatingXmlParser only.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

createRanker

public static edu.ucsb.adl.middleware.DateRanker createRanker(java.lang.String order)
                                                       throws InternalErrorException

Creates a DateRanker. The ranker may be invoked multiple times, but is not multithread-safe.

Parameters:

order - The order of the ranking. "ascending" ("descending") indicates that later (earlier) results have higher rank.

Returns:

A DateRanker.

Throws:

InternalErrorException - If order is invalid.

rank

public double rank(edu.ucsb.adl.middleware.Result result,
                   edu.ucsb.adl.middleware.Query query)
            throws InternalErrorException

Ranks a query result. This method is not multithread-safe.

Specified by:

rank in interface Ranker

Parameters:

result - The result.

query - Unused.

Returns:

The result's rank.

Throws:

InternalErrorException - If an error occurs parsing the report.

startElement

public void startElement(int elementCode,
                         java.lang.String[] attributes)

For use by ValidatingXmlParser only.

Specified by:

startElement in interface XmlHandler

Parameters:

elementCode - The element's code.

attributes - Element attribute values, indexed by attribute code. All of the element's declared attributes are represented in the array; attributes for which a value is specified in the document or for which there is a DTD-specified default have non-null values. The handler should reference the array for the duration of the call only, as it is reused by the parser. Also, the array may be longer than necessary.

endElement

public void endElement(int elementCode)
                throws XmlException

For use by ValidatingXmlParser only.

Specified by:

endElement in interface XmlHandler

Parameters:

elementCode - The element's code.

Throws:

XmlException - If any error occurs.

characters

public void characters(char[] string,
                       int start,
                       int length)

For use by ValidatingXmlParser only.

Specified by:

characters in interface XmlHandler

Parameters:

string - The textual content.

start - The index in string at which the textual content starts.

length - The length of the content.

main

public static void main(java.lang.String[] args)
                 throws java.io.IOException,
                        InternalErrorException

Test driver.

java.io.IOException

InternalErrorException