Cell (apache-cassandra API)

java.lang.Object
- org.apache.cassandra.db.rows.ColumnData
- - org.apache.cassandra.db.rows.Cell<V>

Direct Known Subclasses:

AbstractCell
```
public abstract class Cell<V>
extends ColumnData
```
A cell is our atomic unit for a single value of a single column.
A cell always holds at least a timestamp that gives us how the cell reconcile. We then have 3 main types of cells: 1) live regular cells: those will also have a value and, if for a complex column, a path. 2) expiring cells: on top of regular cells, those have a ttl and a local deletion time (when they are expired). 3) tombstone cells: those won't have value, but they have a local deletion time (when the tombstone was created).

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static interface Cell.Factory<V>

Nested Classes
Modifier and Type	Class and Description
`static interface`	`Cell.Factory<V>`

Field Summary

Fields
Modifier and Type	Field and Description
`static java.util.Comparator<Cell<?>>`	`comparator`
`static int`	`MAX_DELETION_TIME`
`static int`	`NO_DELETION_TIME`
`static int`	`NO_TTL`
`static org.apache.cassandra.db.rows.Cell.Serializer`	`serializer`

Fields inherited from class org.apache.cassandra.db.rows.ColumnData
column

Constructor Summary

Constructors
Modifier Constructor and Description

protected Cell(ColumnMetadata column)

Constructors
Modifier	Constructor and Description
`protected`	`Cell(ColumnMetadata column)`

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`abstract ValueAccessor<V>`	`accessor()`
`java.nio.ByteBuffer`	`buffer()`
`abstract Cell<?>`	`copy(AbstractAllocator allocator)`
`abstract boolean`	`isCounterCell()` Whether the cell is a counter cell or not.
`abstract boolean`	`isExpiring()` Whether the cell is an expiring one or not.
`abstract boolean`	`isLive(int nowInSec)` Whether the cell is live or not given the current time.
`abstract boolean`	`isTombstone()` Whether the cell is a tombstone or not.
`abstract int`	`localDeletionTime()` The cell local deletion time.
`abstract Cell<?>`	`markCounterLocalToBeCleared()`
`abstract CellPath`	`path()` For cells belonging to complex types (non-frozen collection and UDT), the path to the cell.
`abstract Cell<?>`	`purge(DeletionPurger purger, int nowInSec)`
`abstract long`	`timestamp()` The cell timestamp.
`abstract int`	`ttl()` The cell ttl.
`abstract V`	`value()`
`int`	`valueSize()`
`abstract Cell<?>`	`withSkippedValue()` Used to apply the same optimization as in `Cell.Serializer.deserialize(org.apache.cassandra.io.util.DataInputPlus, org.apache.cassandra.db.LivenessInfo, org.apache.cassandra.schema.ColumnMetadata, org.apache.cassandra.db.SerializationHeader, org.apache.cassandra.db.rows.DeserializationHelper, org.apache.cassandra.db.marshal.ValueAccessor<V>)` when the column is not queried but eventhough it's used for digest calculation.
`abstract Cell<?>`	`withUpdatedColumn(ColumnMetadata newColumn)`
`abstract Cell<?>`	`withUpdatedTimestampAndLocalDeletionTime(long newTimestamp, int newLocalDeletionTime)`
`abstract Cell<?>`	`withUpdatedValue(java.nio.ByteBuffer newValue)`

Methods inherited from class org.apache.cassandra.db.rows.ColumnData
column, dataSize, digest, digest, hasInvalidDeletions, maxTimestamp, unsharedHeapSizeExcludingData, updateAllTimestamp, validate

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

- Field Detail
  - NO_TTL
```
public static final int NO_TTL
```
    See Also:
    
    Constant Field Values
  - NO_DELETION_TIME
```
public static final int NO_DELETION_TIME
```
    See Also:
    
    Constant Field Values
  - MAX_DELETION_TIME
```
public static final int MAX_DELETION_TIME
```
    See Also:
    
    Constant Field Values
  - comparator
```
public static final java.util.Comparator<Cell<?>> comparator
```
  - serializer
```
public static final org.apache.cassandra.db.rows.Cell.Serializer serializer
```
- Constructor Detail
  - Cell
```
protected Cell(ColumnMetadata column)
```
- Method Detail
  - isCounterCell
```
public abstract boolean isCounterCell()
```
    Whether the cell is a counter cell or not.
    
    Returns:
    
    whether the cell is a counter cell or not.
  - value
```
public abstract V value()
```
  - accessor
```
public abstract ValueAccessor<V> accessor()
```
  - valueSize
```
public int valueSize()
```
  - buffer
```
public java.nio.ByteBuffer buffer()
```
  - timestamp
```
public abstract long timestamp()
```
    The cell timestamp.
    
    Returns:
    
    the cell timestamp.
  - ttl
```
public abstract int ttl()
```
    The cell ttl.
    
    Returns:
    
    the cell ttl, or NO_TTL if the cell isn't an expiring one.
  - localDeletionTime
```
public abstract int localDeletionTime()
```
    The cell local deletion time.
    
    Returns:
    
    the cell local deletion time, or NO_DELETION_TIME if the cell is neither a tombstone nor an expiring one.
  - isTombstone
```
public abstract boolean isTombstone()
```
    Whether the cell is a tombstone or not.
    
    Returns:
    
    whether the cell is a tombstone or not.
  - isExpiring
```
public abstract boolean isExpiring()
```
    Whether the cell is an expiring one or not.
    Note that this only correspond to whether the cell liveness info have a TTL or not, but doesn't tells whether the cell is already expired or not. You should use isLive(int) for that latter information.
    
    Returns:
    
    whether the cell is an expiring one or not.
  - isLive
```
public abstract boolean isLive(int nowInSec)
```
    Whether the cell is live or not given the current time.
    
    Parameters:
    
    nowInSec - the current time in seconds. This is used to decide if an expiring cell is expired or live.
    
    Returns:
    
    whether the cell is live or not at nowInSec.
  - path
```
public abstract CellPath path()
```
    For cells belonging to complex types (non-frozen collection and UDT), the path to the cell.
    
    Returns:
    
    the cell path for cells of complex column, and null for other cells.
  - withUpdatedColumn
```
public abstract Cell<?> withUpdatedColumn(ColumnMetadata newColumn)
```
  - withUpdatedValue
```
public abstract Cell<?> withUpdatedValue(java.nio.ByteBuffer newValue)
```
  - withUpdatedTimestampAndLocalDeletionTime
```
public abstract Cell<?> withUpdatedTimestampAndLocalDeletionTime(long newTimestamp,
                                                                 int newLocalDeletionTime)
```
  - withSkippedValue
```
public abstract Cell<?> withSkippedValue()
```
    Used to apply the same optimization as in Cell.Serializer.deserialize(org.apache.cassandra.io.util.DataInputPlus, org.apache.cassandra.db.LivenessInfo, org.apache.cassandra.schema.ColumnMetadata, org.apache.cassandra.db.SerializationHeader, org.apache.cassandra.db.rows.DeserializationHelper, org.apache.cassandra.db.marshal.ValueAccessor<V>) when the column is not queried but eventhough it's used for digest calculation.
    
    Returns:
    
    a cell with an empty buffer as value
  - copy
```
public abstract Cell<?> copy(AbstractAllocator allocator)
```
  - markCounterLocalToBeCleared
```
public abstract Cell<?> markCounterLocalToBeCleared()
```
    Specified by:
    
    markCounterLocalToBeCleared in class ColumnData
  - purge
```
public abstract Cell<?> purge(DeletionPurger purger,
                              int nowInSec)
```
    Specified by:
    
    purge in class ColumnData

Class Cell<V>

Nested Class Summary

Field Summary

Fields inherited from class org.apache.cassandra.db.rows.ColumnData

Constructor Summary

Method Summary

Methods inherited from class org.apache.cassandra.db.rows.ColumnData

Methods inherited from class java.lang.Object

Field Detail

NO_TTL

NO_DELETION_TIME

MAX_DELETION_TIME

comparator

serializer

Constructor Detail

Cell

Method Detail

isCounterCell

value

accessor

valueSize

buffer

timestamp

ttl

localDeletionTime

isTombstone

isExpiring

isLive

path

withUpdatedColumn

withUpdatedValue

withUpdatedTimestampAndLocalDeletionTime

withSkippedValue

copy

markCounterLocalToBeCleared

purge