Partition (apache-cassandra API)

All Known Subinterfaces:

CachedPartition

All Known Implementing Classes:

AbstractBTreePartition, AtomicBTreePartition, CachedBTreePartition, FilteredPartition, ImmutableBTreePartition, PartitionUpdate
```
public interface Partition
```
In-memory representation of a Partition. Note that most of the storage engine works through iterators (UnfilteredPartitionIterator) to avoid "materializing" a full partition/query response in memory as much as possible, and so Partition objects should be use as sparingly as possible. There is a couple of cases where we do need to represent partition in-memory (memtables and row cache).

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method and Description
`RegularAndStaticColumns`	`columns()`
`Row`	`getRow(Clustering<?> clustering)` Returns the row corresponding to the provided clustering, or null if there is not such row.
`boolean`	`isEmpty()` Whether the partition object has no informations at all, including any deletion informations.
`TableMetadata`	`metadata()`
`DecoratedKey`	`partitionKey()`
`DeletionTime`	`partitionLevelDeletion()`
`EncodingStats`	`stats()`
`UnfilteredRowIterator`	`unfilteredIterator()` Returns an UnfilteredRowIterator over all the rows/RT contained by this partition.
`UnfilteredRowIterator`	`unfilteredIterator(ColumnFilter columns, java.util.NavigableSet<Clustering<?>> clusteringsInQueryOrder, boolean reversed)` Returns an UnfilteredRowIterator over the rows/RT contained by this partition selected by the provided clusterings.
`UnfilteredRowIterator`	`unfilteredIterator(ColumnFilter columns, Slices slices, boolean reversed)` Returns an UnfilteredRowIterator over the rows/RT contained by this partition selected by the provided slices.

- Method Detail
  - metadata
```
TableMetadata metadata()
```
  - partitionKey
```
DecoratedKey partitionKey()
```
  - partitionLevelDeletion
```
DeletionTime partitionLevelDeletion()
```
  - columns
```
RegularAndStaticColumns columns()
```
  - stats
```
EncodingStats stats()
```
  - isEmpty
```
boolean isEmpty()
```
    Whether the partition object has no informations at all, including any deletion informations.
  - getRow
```
@Nullable
Row getRow(Clustering<?> clustering)
```
    Returns the row corresponding to the provided clustering, or null if there is not such row.
    
    Parameters:
    
    clustering - clustering key to search
    
    Returns:
    
    row corresponding to the clustering, it's either null or non-empty row.
  - unfilteredIterator
```
UnfilteredRowIterator unfilteredIterator()
```
    Returns an UnfilteredRowIterator over all the rows/RT contained by this partition.
  - unfilteredIterator
```
UnfilteredRowIterator unfilteredIterator(ColumnFilter columns,
                                         Slices slices,
                                         boolean reversed)
```
    Returns an UnfilteredRowIterator over the rows/RT contained by this partition selected by the provided slices.
  - unfilteredIterator
```
UnfilteredRowIterator unfilteredIterator(ColumnFilter columns,
                                         java.util.NavigableSet<Clustering<?>> clusteringsInQueryOrder,
                                         boolean reversed)
```
    Returns an UnfilteredRowIterator over the rows/RT contained by this partition selected by the provided clusterings.

Interface Partition

Method Summary

Method Detail

metadata

partitionKey

partitionLevelDeletion

columns

stats

isEmpty

getRow

unfilteredIterator

unfilteredIterator

unfilteredIterator