@Override
  public void delete(Object key) throws IOException {
    long start = stats.startUpdate();
    try {
      Term keyTerm = SerializerUtil.toKeyTerm(key);
      writer.deleteDocuments(keyTerm);
    } finally {
      stats.endUpdate(start);
    }
  }
A repository that writes to a single lucene index writer
geode-lucene/src/main/java/org/apache/geode/cache/lucene/internal/repository/IndexRepositoryImpl.java