RecordReader (Pinot Service Provider Interface 0.12.1 API)

All Superinterfaces:

AutoCloseable, Closeable, Serializable
```
public interface RecordReader
extends Closeable, Serializable
```
The RecordReader interface is used to read records from various file formats into GenericRows. Pinot segments will be generated from GenericRows.
NOTE: for time column, record reader should be able to read both incoming and outgoing time

Method Summary

Modifier and Type	Method	Description
`boolean`	`hasNext()`	Return `true` if more records remain to be read.
`void`	`init(File dataFile, Set<String> fieldsToRead, RecordReaderConfig recordReaderConfig)`	Initializes the record reader with data file, schema and (optional) record reader config.
`GenericRow`	`next()`	Get the next record.
`GenericRow`	`next(GenericRow reuse)`	Get the next record.
`void`	`rewind()`	Rewind the reader to start reading from the first record again.

Methods inherited from interface java.io.Closeable
close

- Method Detail
  - init
```
void init(File dataFile,
          @Nullable
          Set<String> fieldsToRead,
          @Nullable
          RecordReaderConfig recordReaderConfig)
   throws IOException
```
    Initializes the record reader with data file, schema and (optional) record reader config.
    
    Parameters:
    
    dataFile - Data file
    
    fieldsToRead - The fields to read from the data file. If null or empty, reads all fields
    
    recordReaderConfig - Config for the reader specific to the format. e.g. delimiter for csv format etc
    
    Throws:
    
    IOException - If an I/O error occurs
  - hasNext
```
boolean hasNext()
```
    Return true if more records remain to be read.
  - next
```
GenericRow next()
         throws IOException
```
    Get the next record. TODO: Add default implementation because all the override implementations are the same
    
    Throws:
    
    IOException
  - next
```
GenericRow next(GenericRow reuse)
         throws IOException
```
    Get the next record. Re-use the given row to reduce garbage.
    The passed in row should be cleared before calling this method. TODO: Consider clearing the row within the record reader to simplify the caller
    
    Throws:
    
    IOException
  - rewind
```
void rewind()
     throws IOException
```
    Rewind the reader to start reading from the first record again.
    
    Throws:
    
    IOException