parquet-column/src/main/java/org/apache/parquet/column/impl/ColumnWriterBase.java
void finalizeColumnChunk() {
    final DictionaryPage dictionaryPage = dataColumn.toDictPageAndClose();
    if (dictionaryPage != null) {
      if (DEBUG)
        LOG.debug("write dictionary");
      try {
        pageWriter.writeDictionaryPage(dictionaryPage);
      } catch (IOException e) {
        throw new ParquetEncodingException("could not write dictionary page for " + path, e);
      }
      dataColumn.resetDictionary();
    }
  }
void finalizeColumnChunk() {
    final DictionaryPage dictionaryPage = dataColumn.toDictPageAndClose();
    if (dictionaryPage != null) {
      if (DEBUG)
        LOG.debug("write dictionary");
      try {
        pageWriter.writeDictionaryPage(dictionaryPage);
      } catch (IOException e) {
        throw new ParquetEncodingException("could not write dictionary page for " + path, e);
      }
      dataColumn.resetDictionary();
    }
  }
Finalizes the Column chunk. Possibly adding extra pages if needed (dictionary, ...)
Is called right after writePage