RowMapping (apache-cassandra API)

java.lang.Object
- org.apache.cassandra.index.sai.disk.RowMapping

```
@NotThreadSafe
public class RowMapping
extends java.lang.Object
```
In memory representation of PrimaryKey to row ID mappings which only contains Row regardless of whether it's live or deleted. (RangeTombstoneMarker is not included.)
While this inherits the threading behaviour of InMemoryTrie of single-writer / multiple-reader, since it is only used by StorageAttachedIndexWriter, which is not threadsafe, we can consider this class not threadsafe as well.

Field Summary

Fields
Modifier and Type Field Description

static RowMapping DUMMY

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`add(PrimaryKey key, long sstableRowId)`	Include PrimaryKey to RowId mapping
`void`	`complete()`	Complete building in memory RowMapping, mark it as immutable.
`static RowMapping`	`create(OperationType opType)`	Create row mapping for FLUSH operation only.
`int`	`get(PrimaryKey key)`	Returns the SSTable row ID for a `PrimaryKey`
`boolean`	`isComplete()`
`java.util.Iterator<Pair<ByteComparable,com.carrotsearch.hppc.LongArrayList>>`	`merge(MemtableIndex index)`	Link the term -> `PrimaryKeys` mappings from a provided `MemtableIndex` to the `PrimaryKey` -> row ID mappings maintained here in `rowMapping` to produce mappings of terms to their postings lists.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - DUMMY
```
public static final RowMapping DUMMY
```
- Method Detail
  - create
```
public static RowMapping create(OperationType opType)
```
    Create row mapping for FLUSH operation only.
  - merge
```
public java.util.Iterator<Pair<ByteComparable,com.carrotsearch.hppc.LongArrayList>> merge(MemtableIndex index)
```
    Link the term -> PrimaryKeys mappings from a provided MemtableIndex to the PrimaryKey -> row ID mappings maintained here in rowMapping to produce mappings of terms to their postings lists.
    
    Parameters:
    
    index - a Memtable-attached column index
    
    Returns:
    
    an iterator of term -> postings list Pairs
  - complete
```
public void complete()
```
    Complete building in memory RowMapping, mark it as immutable.
  - isComplete
```
public boolean isComplete()
```
  - add
```
public void add(PrimaryKey key,
                long sstableRowId)
         throws InMemoryTrie.SpaceExhaustedException
```
    Include PrimaryKey to RowId mapping
    
    Throws:
    
    InMemoryTrie.SpaceExhaustedException
  - get
```
public int get(PrimaryKey key)
```
    Returns the SSTable row ID for a PrimaryKey
    
    Parameters:
    
    key - the PrimaryKey
    
    Returns:
    
    a valid SSTable row ID for the PrimaryKey or -1 if the PrimaryKey doesn't exist in the RowMapping