parquet-hadoop/src/main/java/org/apache/parquet/hadoop/ParquetFileReader.java
public DictionaryPageReadStore getNextDictionaryReader() {
    if (nextDictionaryReader == null && currentBlock < blocks.size()) {
      this.nextDictionaryReader = getDictionaryReader(blocks.get(currentBlock));
    }
    return nextDictionaryReader;
  }
public DictionaryPageReadStore getNextDictionaryReader() {
    if (nextDictionaryReader == null && currentBlock < blocks.size()) {
      this.nextDictionaryReader = getDictionaryReader(blocks.get(currentBlock));
    }
    return nextDictionaryReader;
  }
Returns a {@link DictionaryPageReadStore} for the row group that would be
returned by calling {@link #readNextRowGroup()} or skipped by calling
{@link #skipNextRowGroup()}.

@return a DictionaryPageReadStore for the next row group