Example #1
0
        public void TestGetTermSet()
        {
            BooleanQuery query = new BooleanQuery();

            query.Add(new TermQuery(new Term(F, "A")), Occur.MUST);
            query.Add(new TermQuery(new Term(F, "B")), Occur.MUST);
            query.Add(new TermQuery(new Term("x", "C")), Occur.SHOULD);

            BooleanQuery innerQuery = new BooleanQuery();

            innerQuery.Add(new TermQuery(new Term(F, "D")), Occur.MUST);
            innerQuery.Add(new TermQuery(new Term(F, "E")), Occur.MUST);
            query.Add(innerQuery, Occur.MUST_NOT);

            FieldQuery fq = new FieldQuery(query, true, true);

            assertEquals(2, fq.termSetMap.size());
            ISet <String> termSet = fq.GetTermSet(F);

            assertEquals(2, termSet.size());
            assertTrue(termSet.contains("A"));
            assertTrue(termSet.contains("B"));
            termSet = fq.GetTermSet("x");
            assertEquals(1, termSet.size());
            assertTrue(termSet.contains("C"));
            termSet = fq.GetTermSet("y");
            assertNull(termSet);
        }
Example #2
0
        //public static void main( string[] args ) throws Exception {
        //  Analyzer analyzer = new WhitespaceAnalyzer(Version.LUCENE_CURRENT);
        //  QueryParser parser = new QueryParser(Version.LUCENE_CURRENT,  "f", analyzer );
        //  Query query = parser.parse( "a x:b" );
        //  FieldQuery fieldQuery = new FieldQuery( query, true, false );

        //  Directory dir = new RAMDirectory();
        //  IndexWriter writer = new IndexWriter(dir, new IndexWriterConfig(Version.LUCENE_CURRENT, analyzer));
        //  Document doc = new Document();
        //  IndexableFieldType ft = new IndexableFieldType(TextField.TYPE_STORED);
        //  ft.setStoreTermVectors(true);
        //  ft.setStoreTermVectorOffsets(true);
        //  ft.setStoreTermVectorPositions(true);
        //  doc.add( new Field( "f", ft, "a a a b b c a b b c d e f" ) );
        //  doc.add( new Field( "f", ft, "b a b a f" ) );
        //  writer.addDocument( doc );
        //  writer.close();

        //  IndexReader reader = IndexReader.open(dir1);
        //  new FieldTermStack( reader, 0, "f", fieldQuery );
        //  reader.close();
        //}

        /// <summary>
        /// a constructor.
        /// </summary>
        /// <param name="reader"><see cref="IndexReader"/> of the index</param>
        /// <param name="docId">document id to be highlighted</param>
        /// <param name="fieldName">field of the document to be highlighted</param>
        /// <param name="fieldQuery"><see cref="FieldQuery"/> object</param>
        /// <exception cref="IOException">If there is a low-level I/O error</exception>
        public FieldTermStack(IndexReader reader, int docId, string fieldName, FieldQuery fieldQuery)
        {
            this.fieldName = fieldName;

            ISet <string> termSet = fieldQuery.GetTermSet(fieldName);

            // just return to make null snippet if un-matched fieldName specified when fieldMatch == true
            if (termSet == null)
            {
                return;
            }

            Fields vectors = reader.GetTermVectors(docId);

            if (vectors == null)
            {
                // null snippet
                return;
            }

            Terms vector = vectors.GetTerms(fieldName);

            if (vector == null)
            {
                // null snippet
                return;
            }

            CharsRef             spare     = new CharsRef();
            TermsEnum            termsEnum = vector.GetEnumerator();
            DocsAndPositionsEnum dpEnum    = null;
            BytesRef             text;

            int numDocs = reader.MaxDoc;

            while (termsEnum.MoveNext())
            {
                text = termsEnum.Term;
                UnicodeUtil.UTF8toUTF16(text, spare);
                string term = spare.ToString();
                if (!termSet.Contains(term))
                {
                    continue;
                }
                dpEnum = termsEnum.DocsAndPositions(null, dpEnum);
                if (dpEnum == null)
                {
                    // null snippet
                    return;
                }

                dpEnum.NextDoc();

                // For weight look here: http://lucene.apache.org/core/3_6_0/api/core/org/apache/lucene/search/DefaultSimilarity.html
                float weight = (float)(Math.Log(numDocs / (double)(reader.DocFreq(new Term(fieldName, text)) + 1)) + 1.0);

                int freq = dpEnum.Freq;

                for (int i = 0; i < freq; i++)
                {
                    int pos = dpEnum.NextPosition();
                    if (dpEnum.StartOffset < 0)
                    {
                        return; // no offsets, null snippet
                    }
                    termList.Add(new TermInfo(term, dpEnum.StartOffset, dpEnum.EndOffset, pos, weight));
                }
            }

            // sort by position
            CollectionUtil.TimSort(termList);

            // now look for dups at the same position, linking them together
            int      currentPos = -1;
            TermInfo previous   = null;
            TermInfo first      = null;

            for (int i = 0; i < termList.Count;)
            {
                TermInfo current = termList[i];
                if (current.Position == currentPos)
                {
                    if (Debugging.AssertsEnabled)
                    {
                        Debugging.Assert(previous != null);
                    }
                    previous.SetNext(current);
                    previous = current;
                    //iterator.Remove();

                    // LUCENENET NOTE: Remove, but don't advance the i position (since removing will advance to the next item)
                    termList.RemoveAt(i);
                }
                else
                {
                    if (previous != null)
                    {
                        previous.SetNext(first);
                    }
                    previous   = first = current;
                    currentPos = current.Position;

                    // LUCENENET NOTE: Only increment the position if we don't do a delete.
                    i++;
                }
            }

            if (previous != null)
            {
                previous.SetNext(first);
            }
        }