Here is whole in memory index and search example. I have just written in for my self and it works perfectly. I understand that you need to store index in memory, but the question is why you need MemoryIndex
for that? You simply use RAMDirectory
instead and your index will be stored in memory, so when you perform your search, index will be loaded from RAMDirectory (memory).
StandardAnalyzer analyzer = new StandardAnalyzer(Version.LUCENE_34);
IndexWriterConfig config = new IndexWriterConfig(Version.LUCENE_34, analyzer);
RAMDirectory directory = new RAMDirectory();
try {
IndexWriter indexWriter = new IndexWriter(directory, config);
Document doc = new Document();
doc.add(new Field("content", text, Field.Store.YES, Field.Index.ANALYZED, Field.TermVector.WITH_OFFSETS));
indexWriter.addDocument(doc);
indexWriter.optimize();
indexWriter.close();
QueryParser parser = new QueryParser(Version.LUCENE_34, "content", analyzer);
IndexSearcher searcher = new IndexSearcher(directory, true);
IndexReader reader = IndexReader.open(directory, true);
Query query = parser.parse(word);
TopScoreDocCollector collector = TopScoreDocCollector.create(10000, true);
searcher.search(query, collector);
ScoreDoc[] hits = collector.topDocs().scoreDocs;
if (hits != null && hits.length > 0) {
for (ScoreDoc hit : hits) {
int docId = hit.doc;
Document hitDoc = searcher.doc(docId);
TermFreqVector termFreqVector = reader.getTermFreqVector(docId, "content");
TermPositionVector termPositionVector = (TermPositionVector) termFreqVector;
int termIndex = termFreqVector.indexOf(word);
TermVectorOffsetInfo[] termVectorOffsetInfos = termPositionVector.getOffsets(termIndex);
for (TermVectorOffsetInfo termVectorOffsetInfo : termVectorOffsetInfos) {
concordances.add(processor.processConcordance(hitDoc.get("content"), word, termVectorOffsetInfo.getStartOffset(), size));
}
}
}
analyzer.close();
searcher.close();
directory.close();