Package org.apache.cassandra.db

Class DecoratedKey

java.lang.Object

org.apache.cassandra.db.DecoratedKey

All Implemented Interfaces:

java.lang.Comparable<PartitionPosition>, PartitionPosition, RingPosition<PartitionPosition>, IFilter.FilterKey

Direct Known Subclasses:

BufferDecoratedKey, NativeDecoratedKey

public abstract class DecoratedKey
extends java.lang.Object
implements PartitionPosition, IFilter.FilterKey

Represents a decorated key, handy for certain operations where just working with strings gets slow. We do a lot of sorting of DecoratedKeys, so for speed, we assume that tokens correspond one-to-one with keys. This is not quite correct in the case of RandomPartitioner (which uses MD5 to hash keys to tokens); if this matters, you can subclass RP to use a stronger hash, or use a non-lossy tokenization scheme (as in the OrderPreservingPartitioner classes).

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.cassandra.db.PartitionPosition

PartitionPosition.ForKey, PartitionPosition.Kind, PartitionPosition.RowPositionSerializer

Field Summary

Fields

Modifier and Type	Field	Description
static java.util.Comparator<DecoratedKey>	comparator

Fields inherited from interface org.apache.cassandra.db.PartitionPosition

serializer

Constructor Summary

Constructors

Constructor	Description
DecoratedKey(Token token)

Method Summary

Modifier and Type	Method	Description
int	compareTo(PartitionPosition pos)
static int	compareTo(IPartitioner partitioner, java.nio.ByteBuffer key, PartitionPosition position)
boolean	equals(java.lang.Object obj)
void	filterHash(long[] dest)	Places the murmur3 hash of the key in the given long array of size at least two.
abstract java.nio.ByteBuffer	getKey()
IPartitioner	getPartitioner()
Token	getToken()
int	hashCode()
boolean	isMinimum()
PartitionPosition.Kind	kind()
Token.KeyBound	minValue()
java.lang.String	toCQLString(TableMetadata metadata)	Returns a CQL representation of this key.
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

comparator

public static final java.util.Comparator<DecoratedKey> comparator

Constructor Detail

DecoratedKey

public DecoratedKey(Token token)

Method Detail

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

compareTo

public int compareTo(PartitionPosition pos)

Specified by:

compareTo in interface java.lang.Comparable<PartitionPosition>

compareTo

public static int compareTo(IPartitioner partitioner,
                            java.nio.ByteBuffer key,
                            PartitionPosition position)

getPartitioner

public IPartitioner getPartitioner()

Specified by:

getPartitioner in interface RingPosition<PartitionPosition>

minValue

public Token.KeyBound minValue()

Specified by:

minValue in interface RingPosition<PartitionPosition>

isMinimum

public boolean isMinimum()

Specified by:

isMinimum in interface PartitionPosition

Specified by:

isMinimum in interface RingPosition<PartitionPosition>

kind

public PartitionPosition.Kind kind()

Specified by:

kind in interface PartitionPosition

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

toCQLString

public java.lang.String toCQLString(TableMetadata metadata)

Returns a CQL representation of this key.

Parameters:

metadata - the metadata of the table that this key belogs to

Returns:

a CQL representation of this key

getToken

public Token getToken()

Specified by:

getToken in interface RingPosition<PartitionPosition>

getKey

public abstract java.nio.ByteBuffer getKey()

filterHash

public void filterHash(long[] dest)

Description copied from interface: IFilter.FilterKey

Places the murmur3 hash of the key in the given long array of size at least two.

Specified by:

filterHash in interface IFilter.FilterKey