public class InferredSchema
If passed a CSV file that contains a header and a single row of sample data, it will return
Only Double, Integer, Long, and String types are supported. If no number type can be inferred,
the field type will become the default type. Note that if your column is actually categorical but
is represented as a number, you will need to do additional transformation. Also, if your sample
field is blank/null, it will also become the default type.