Jérôme,
Thanks for think link you sent earlier. I've read through that
discussion and I think my problem must be related, but I'm still banging my
head against it. I'm pretty sure that there's something I'm missing about how
the queries get added together.
As it stands my query filter seems to modify the ranking, but doesn't
affect the results returned. I've pasted my code bellow and I'd appreciate it
if someone could take a look and let me know if they see the problem.
Thanks,
Jake.
public class MetaQueryFilter implements QueryFilter {
private static final Logger LOG = LogFormatter
.getLogger(MetaQueryFilter.class.getName());
/**
* Need to pull out the list of meta tags from the configuration
*/
private static String [] META_TAGS =
NutchConf.get().getStrings("meta.names");
/**
* We're going to go through and create search filters for each of the
meta-tags we were asked to index.
*/
public BooleanQuery filter(Query input, BooleanQuery output) {
// If no meta-tags were specified in the conf file, then
don't bother wasting cycles
if ( META_TAGS.equals(null) ) {
return output;
}
addTerms(input, output);
return output;
}
private static void addTerms(Query input, BooleanQuery output) {
Clause[] clauses = input.getClauses();
for (int x = 0; x < clauses.length; x++) {
Clause c = clauses[x];
if
(!c.getField().equals(Clause.DEFAULT_FIELD))
continue; // skip
non-default fields
// These are the fields we're interested in
indexing
String [] tagsToIndex = META_TAGS;
for (int i = 0; i < tagsToIndex.length; ++i) {
LOG.info("Meta Query Filter:
Adding a search for " + tagsToIndex[i]);
Term term = new
Term(tagsToIndex[i], c.getTerm().toString());
// add a lucene PhraseQuery
for this tag
PhraseQuery metaQuery = new
PhraseQuery();
metaQuery.setSlop(0);
metaQuery.add(term);
// set boost
metaQuery.setBoost(2.0f);
// add it as a specified query
output.add(metaQuery, false,
false);
}
}
}
}
