parquet-hadoop/src/main/java/org/apache/parquet/hadoop/ParquetFileWriter.java
public void start() throws IOException {
    state = state.start();
    LOG.debug("{}: start", out.getPos());
    out.write(MAGIC);
  }
public void start() throws IOException {
    state = state.start();
    LOG.debug("{}: start", out.getPos());
    out.write(MAGIC);
  }
start the file
@throws IOException if there is an error while writing