Examples with TopFieldCollector org.apache.lucene.search.TopFieldCollector used on opensource projects

Example 6 with TopFieldCollector

use of org.apache.lucene.search.TopFieldCollector in project lucene-solr by apache.

the class AnalyzingInfixSuggester method lookup.

/**
   * This is an advanced method providing the capability to send down to the suggester any 
   * arbitrary lucene query to be used to filter the result of the suggester
   * 
   * @param key the keyword being looked for
   * @param contextQuery an arbitrary Lucene query to be used to filter the result of the suggester. {@link #addContextToQuery} could be used to build this contextQuery.
   * @param num number of items to return
   * @param allTermsRequired all searched terms must match or not
   * @param doHighlight if true, the matching term will be highlighted in the search result
   * @return the result of the suggester
   * @throws IOException f the is IO exception while reading data from the index
   */
public List<LookupResult> lookup(CharSequence key, BooleanQuery contextQuery, int num, boolean allTermsRequired, boolean doHighlight) throws IOException {
    if (searcherMgr == null) {
        throw new IllegalStateException("suggester was not built");
    }
    final BooleanClause.Occur occur;
    if (allTermsRequired) {
        occur = BooleanClause.Occur.MUST;
    } else {
        occur = BooleanClause.Occur.SHOULD;
    }
    BooleanQuery.Builder query;
    Set<String> matchedTokens;
    String prefixToken = null;
    try (TokenStream ts = queryAnalyzer.tokenStream("", new StringReader(key.toString()))) {
        //long t0 = System.currentTimeMillis();
        ts.reset();
        final CharTermAttribute termAtt = ts.addAttribute(CharTermAttribute.class);
        final OffsetAttribute offsetAtt = ts.addAttribute(OffsetAttribute.class);
        String lastToken = null;
        query = new BooleanQuery.Builder();
        int maxEndOffset = -1;
        matchedTokens = new HashSet<>();
        while (ts.incrementToken()) {
            if (lastToken != null) {
                matchedTokens.add(lastToken);
                query.add(new TermQuery(new Term(TEXT_FIELD_NAME, lastToken)), occur);
            }
            lastToken = termAtt.toString();
            if (lastToken != null) {
                maxEndOffset = Math.max(maxEndOffset, offsetAtt.endOffset());
            }
        }
        ts.end();
        if (lastToken != null) {
            Query lastQuery;
            if (maxEndOffset == offsetAtt.endOffset()) {
                // Use PrefixQuery (or the ngram equivalent) when
                // there was no trailing discarded chars in the
                // string (e.g. whitespace), so that if query does
                // not end with a space we show prefix matches for
                // that token:
                lastQuery = getLastTokenQuery(lastToken);
                prefixToken = lastToken;
            } else {
                // Use TermQuery for an exact match if there were
                // trailing discarded chars (e.g. whitespace), so
                // that if query ends with a space we only show
                // exact matches for that term:
                matchedTokens.add(lastToken);
                lastQuery = new TermQuery(new Term(TEXT_FIELD_NAME, lastToken));
            }
            if (lastQuery != null) {
                query.add(lastQuery, occur);
            }
        }
        if (contextQuery != null) {
            boolean allMustNot = true;
            for (BooleanClause clause : contextQuery.clauses()) {
                if (clause.getOccur() != BooleanClause.Occur.MUST_NOT) {
                    allMustNot = false;
                    break;
                }
            }
            if (allMustNot) {
                // All are MUST_NOT: add the contextQuery to the main query instead (not as sub-query)
                for (BooleanClause clause : contextQuery.clauses()) {
                    query.add(clause);
                }
            } else if (allTermsRequired == false) {
                // We must carefully upgrade the query clauses to MUST:
                BooleanQuery.Builder newQuery = new BooleanQuery.Builder();
                newQuery.add(query.build(), BooleanClause.Occur.MUST);
                newQuery.add(contextQuery, BooleanClause.Occur.MUST);
                query = newQuery;
            } else {
                // Add contextQuery as sub-query
                query.add(contextQuery, BooleanClause.Occur.MUST);
            }
        }
    }
    // TODO: we could allow blended sort here, combining
    // weight w/ score.  Now we ignore score and sort only
    // by weight:
    Query finalQuery = finishQuery(query, allTermsRequired);
    //System.out.println("finalQuery=" + finalQuery);
    // Sort by weight, descending:
    TopFieldCollector c = TopFieldCollector.create(SORT, num, true, false, false);
    // We sorted postings by weight during indexing, so we
    // only retrieve the first num hits now:
    Collector c2 = new EarlyTerminatingSortingCollector(c, SORT, num);
    List<LookupResult> results = null;
    SearcherManager mgr;
    IndexSearcher searcher;
    synchronized (searcherMgrLock) {
        // acquire & release on same SearcherManager, via local reference
        mgr = searcherMgr;
        searcher = mgr.acquire();
    }
    try {
        //System.out.println("got searcher=" + searcher);
        searcher.search(finalQuery, c2);
        TopFieldDocs hits = c.topDocs();
        // Slower way if postings are not pre-sorted by weight:
        // hits = searcher.search(query, null, num, SORT);
        results = createResults(searcher, hits, num, key, doHighlight, matchedTokens, prefixToken);
    } finally {
        mgr.release(searcher);
    }
    return results;
}

Example 7 with TopFieldCollector

use of org.apache.lucene.search.TopFieldCollector in project graphdb by neo4j-attic.

the class TopDocsIterator method toTopDocs.

private TopDocs toTopDocs(Query query, QueryContext context, Searcher searcher) throws IOException {
    Sort sorting = context != null ? context.getSorting() : null;
    TopDocs topDocs = null;
    if (sorting == null) {
        topDocs = searcher.search(query, context.getTop());
    } else {
        boolean forceScore = context == null || !context.getTradeCorrectnessForSpeed();
        if (forceScore) {
            TopFieldCollector collector = LuceneDataSource.scoringCollector(sorting, context.getTop());
            searcher.search(query, collector);
            topDocs = collector.topDocs();
        } else {
            topDocs = searcher.search(query, null, context.getTop(), sorting);
        }
    }
    return topDocs;
}

Example 8 with TopFieldCollector

use of org.apache.lucene.search.TopFieldCollector in project graphdb by neo4j-attic.

the class HitDoc method getMoreDocs.

/**
   * Tries to add new documents to hitDocs.
   * Ensures that the hit numbered <code>min</code> has been retrieved.
   */
private final void getMoreDocs(int min) throws IOException {
    if (hitDocs.size() > min) {
        min = hitDocs.size();
    }
    // double # retrieved
    int n = min * 2;
    //  TopDocs topDocs = (sort == null) ? searcher.search(weight, filter, n) : searcher.search(weight, filter, n, sort);
    TopDocs topDocs = null;
    if (sort == null) {
        topDocs = searcher.search(weight, filter, n);
    } else {
        if (this.score) {
            TopFieldCollector collector = LuceneDataSource.scoringCollector(sort, n);
            searcher.search(weight, null, collector);
            topDocs = collector.topDocs();
        } else {
            topDocs = searcher.search(weight, filter, n, sort);
        }
    }
    length = topDocs.totalHits;
    ScoreDoc[] scoreDocs = topDocs.scoreDocs;
    float scoreNorm = 1.0f;
    if (length > 0 && topDocs.getMaxScore() > 1.0f) {
        scoreNorm = 1.0f / topDocs.getMaxScore();
    }
    int start = hitDocs.size() - nDeletedHits;
    // any new deletions?
    int nDels2 = countDeletions(searcher);
    debugCheckedForDeletions = false;
    if (nDeletions < 0 || nDels2 > nDeletions) {
        // either we cannot count deletions, or some "previously valid hits" might have been deleted, so find exact start point
        nDeletedHits = 0;
        debugCheckedForDeletions = true;
        int i2 = 0;
        for (int i1 = 0; i1 < hitDocs.size() && i2 < scoreDocs.length; i1++) {
            int id1 = ((HitDoc) hitDocs.get(i1)).id;
            int id2 = scoreDocs[i2].doc;
            if (id1 == id2) {
                i2++;
            } else {
                nDeletedHits++;
            }
        }
        start = i2;
    }
    int end = scoreDocs.length < length ? scoreDocs.length : length;
    length += nDeletedHits;
    for (int i = start; i < end; i++) {
        hitDocs.addElement(new HitDoc(scoreDocs[i].score * scoreNorm, scoreDocs[i].doc));
    }
    nDeletions = nDels2;
}

Example 9 with TopFieldCollector

use of org.apache.lucene.search.TopFieldCollector in project neo4j-mobile-android by neo4j-contrib.

the class TopDocsIterator method toTopDocs.

private TopDocs toTopDocs(Query query, QueryContext context, IndexSearcher searcher) throws IOException {
    Sort sorting = context != null ? context.getSorting() : null;
    TopDocs topDocs = null;
    if (sorting == null) {
        topDocs = searcher.search(query, context.getTop());
    } else {
        boolean forceScore = context == null || !context.getTradeCorrectnessForSpeed();
        if (forceScore) {
            TopFieldCollector collector = LuceneDataSource.scoringCollector(sorting, context.getTop());
            searcher.search(query, collector);
            topDocs = collector.topDocs();
        } else {
            topDocs = searcher.search(query, null, context.getTop(), sorting);
        }
    }
    return topDocs;
}

Example 10 with TopFieldCollector

use of org.apache.lucene.search.TopFieldCollector in project neo4j by neo4j.

the class TopDocsIterator method toTopDocs.

private TopDocs toTopDocs(Query query, QueryContext context, IndexSearcher searcher) throws IOException {
    Sort sorting = context != null ? context.getSorting() : null;
    TopDocs topDocs;
    if (sorting == null && context != null) {
        topDocs = searcher.search(query, context.getTop());
    } else {
        if (context == null || !context.getTradeCorrectnessForSpeed()) {
            TopFieldCollector collector = LuceneDataSource.scoringCollector(sorting, context.getTop());
            searcher.search(query, collector);
            topDocs = collector.topDocs();
        } else {
            topDocs = searcher.search(query, null, context.getTop(), sorting);
        }
    }
    return topDocs;
}