parquet-protobuf/src/main/java/org/apache/parquet/proto/ProtoSchemaConverter.java
private <T> GroupBuilder<T> convertFields(GroupBuilder<T> groupBuilder, List<FieldDescriptor> fieldDescriptors) {
    for (FieldDescriptor fieldDescriptor : fieldDescriptors) {
      groupBuilder =
          addField(fieldDescriptor, groupBuilder)
          .id(fieldDescriptor.getNumber())
          .named(fieldDescriptor.getName());
    }
    return groupBuilder;
  }
private <T> GroupBuilder<T> convertFields(GroupBuilder<T> groupBuilder, List<FieldDescriptor> fieldDescriptors) {
    for (FieldDescriptor fieldDescriptor : fieldDescriptors) {
      groupBuilder =
          addField(fieldDescriptor, groupBuilder)
          .id(fieldDescriptor.getNumber())
          .named(fieldDescriptor.getName());
    }
    return groupBuilder;
  }
/* Iterates over list of fields. *