All Superinterfaces:

Serializable

All Known Implementing Classes:

ExpressionBasedOperation.NegativeRowMapper, ExpressionBasedOperation.PositiveRowMapper, RowInRecordMapper
```
public interface RecordMapper
extends Serializable
```
A function applied to a record, returning a list of rows to replace it. They do not need to form a single record.

Field Summary

Fields
Modifier and Type Field Description

static RecordMapper IDENTITY
Returns unchanged records.

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method	Description
`List<Row>`	`call(Record record)`	Maps a record to a list of rows.
`static RecordMapper`	`conditionalMapper(RecordFilter filter, RecordMapper positive, RecordMapper negative)`	Returns a mapper which applies one of the two mappers provided depending on the outcome of the filter.
`boolean`	`preservesRecordStructure()`	If the record structure is preserved by the mapper, set this boolean to true.
`default boolean`	`preservesRowCount()`	If every record is mapped to a list with the same number of rows as what the record contains, set this boolean to true.
`static RecordMapper`	`rowWiseRecordMapper(RowMapper mapper)`	Applies a row mapper on all rows in the record.

- Field Detail
  - IDENTITY
```
static final RecordMapper IDENTITY
```
    Returns unchanged records.
- Method Detail
  - call
```
List<Row> call(Record record)
```
    Maps a record to a list of rows. The rows may not form a single record, unless preservesRecordStructure() is true.
  - preservesRowCount
```
default boolean preservesRowCount()
```
    If every record is mapped to a list with the same number of rows as what the record contains, set this boolean to true. This helps the underlying implementation avoid recomputing row ids.
  - preservesRecordStructure
```
boolean preservesRecordStructure()
```
    If the record structure is preserved by the mapper, set this boolean to true. This will help the runner avoid re-computing the record boundaries after applying this mapper.
  - rowWiseRecordMapper
```
static RecordMapper rowWiseRecordMapper(RowMapper mapper)
```
    Applies a row mapper on all rows in the record.
  - conditionalMapper
```
static RecordMapper conditionalMapper(RecordFilter filter,
                                      RecordMapper positive,
                                      RecordMapper negative)
```
    Returns a mapper which applies one of the two mappers provided depending on the outcome of the filter. If the filter evaluates to true, the positive mapper is evaluated, otherwise the negative one is used.
    
    Parameters:
    
    filter - the filter to use for the disjunction
    
    positive - what to do if the filter evaluates to true
    
    negative - what to do otherwise
    
    Returns:
    
    the conditional mapper

Interface RecordMapper

Field Summary

Method Summary

Field Detail

IDENTITY

Method Detail

call

preservesRowCount

preservesRecordStructure

rowWiseRecordMapper

conditionalMapper