Java 类org.apache.lucene.search.suggest.DocumentDictionary 实例源码

/**
 * Rebuild a suggestion index from the document index.
 *
 * This method iterates through the entire document index and makes sure that only unique titles
 * are indexed.
 *
 * @param indexRoot The parent directory inside which both the document index and the suggestion
 *                  index lives.
 * @throws IOException
 */
public static void rebuild(String indexRoot) throws IOException {
  Path indexRootPath = Paths.get(indexRoot);
  Path suggestionPath = getSuggestionIndexPath(indexRootPath);

  // Delete the suggestion index if it exists.
  if (Files.exists(suggestionPath)) {
    Util.deletePath(suggestionPath);
  }

  // Create the suggestion index.
  Analyzer analyzer = Indexer.getAnalyzer();
  Directory suggestionDir = FSDirectory.open(getSuggestionIndexPath(indexRootPath));
  AnalyzingInfixSuggester suggester = new AnalyzingInfixSuggester(suggestionDir, analyzer);

  // Open the document index.
  Directory indexDir = FSDirectory.open(Indexer.getMainIndexPath(indexRootPath));
  IndexReader reader = DirectoryReader.open(indexDir);

  // Get a document iterator.
  DocumentDictionary docDict = new DocumentDictionary(reader, Indexer.TITLE_FIELD_NAME, null);
  InputIterator iterator = docDict.getEntryIterator();
  Set<BytesRef> titleSet = new HashSet<>();
  BytesRef next;
  while ((next = iterator.next()) != null) {
    if (titleSet.contains(next)) {
      continue;
    }

    titleSet.add(next);
    suggester.add(next, null, 0, null);
  }

  reader.close();

  suggester.commit();
  suggester.close();
}

@Override
public Dictionary create(SolrCore core, SolrIndexSearcher searcher) {
  if(params == null) {
    // should not happen; implies setParams was not called
    throw new IllegalStateException("Value of params not set");
  }
  String field = (String) params.get(FIELD);
  String weightField = (String) params.get(WEIGHT_FIELD);
  String payloadField = (String) params.get(PAYLOAD_FIELD);

  if (field == null) {
    throw new IllegalArgumentException(FIELD + " is a mandatory parameter");
  }
  if (weightField == null) {
    throw new IllegalArgumentException(WEIGHT_FIELD + " is a mandatory parameter");
  }

  return new DocumentDictionary(searcher.getIndexReader(), field, weightField, payloadField);
}

@Override
public Dictionary create(SolrCore core, SolrIndexSearcher searcher) {
  if(params == null) {
    // should not happen; implies setParams was not called
    throw new IllegalStateException("Value of params not set");
  }
  String field = (String) params.get(FIELD);
  String weightField = (String) params.get(WEIGHT_FIELD);
  String payloadField = (String) params.get(PAYLOAD_FIELD);

  if (field == null) {
    throw new IllegalArgumentException(FIELD + " is a mandatory parameter");
  }
  if (weightField == null) {
    throw new IllegalArgumentException(WEIGHT_FIELD + " is a mandatory parameter");
  }

  return new DocumentDictionary(searcher.getIndexReader(), field, weightField, payloadField);
}

@Override
public Dictionary create(SolrCore core, SolrIndexSearcher searcher) {
  if(params == null) {
    // should not happen; implies setParams was not called
    throw new IllegalStateException("Value of params not set");
  }
  String field = (String) params.get(FIELD);
  String weightField = (String) params.get(WEIGHT_FIELD);
  String payloadField = (String) params.get(PAYLOAD_FIELD);

  if (field == null) {
    throw new IllegalArgumentException(FIELD + " is a mandatory parameter");
  }
  if (weightField == null) {
    throw new IllegalArgumentException(WEIGHT_FIELD + " is a mandatory parameter");
  }

  return new DocumentDictionary(searcher.getIndexReader(), field, weightField, payloadField);
}

private void buildSuggesterIndex() throws IOException {
    try (DirectoryReader reader = DirectoryReader.open(indexDir)) {
        final Dictionary dictionary = new DocumentDictionary(reader, "content", null, null, "username");
        suggester.build(dictionary);
        suggester.refresh();
    }
}