Review

class IndexWriter {
  /**
   * Deletes the document(s) matching the provided query.
   *
   * <p><b>NOTE</b>: if this method hits an OutOfMemoryError
   * you should immediately close the writer.  See <a
   * href="#OOME">above</a> for details.</p>
   *
   * @param query the query to identify the documents to be deleted
   * @throws CorruptIndexException if the index is corrupt
   * @throws IOException if there is a low-level IO error
   */
  public void deleteDocuments(Query query) throws CorruptIndexException, IOException {
    ensureOpen();
    boolean doFlush = docWriter.bufferDeleteQuery(query);
    if (doFlush)
      flush(true, false, false);
  }

}