org.kitesdk.data.spi

Class PartitionKey

java.lang.Object

org.kitesdk.data.spi.PartitionKey

@NotThreadSafe
public class PartitionKey
extends Object

A key for retrieving partitions from a Dataset.

A PartitionKey is an ordered sequence of values corresponding to the FieldPartitioners in a PartitionStrategy. You can obtain a PartitionKey using partitionKeyForEntity(org.kitesdk.data.PartitionStrategy, Object, EntityAccessor, PartitionKey).

Implementations of PartitionKey are typically not thread-safe; that is, the behavior when accessing a single instance from multiple threads is undefined.

See Also:

PartitionStrategy, FieldPartitioner, Dataset

Constructor Summary

Constructors

Constructor and Description
PartitionKey(Object... values)

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(Object o)
Object	get(int index) Return the value at the specified index in the key.
int	getLength() Return the number of values in the key.
List<Object>	getValues()
int	hashCode()
static <E> PartitionKey	partitionKeyForEntity(PartitionStrategy strategy, E entity, EntityAccessor<E> accessor) Construct a partition key for the given entity.
static <E> PartitionKey	partitionKeyForEntity(PartitionStrategy strategy, E entity, EntityAccessor<E> accessor, PartitionKey reuseKey) Construct a partition key for the given entity, reusing the supplied key if not null.
protected void	set(int index, Object value)
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

PartitionKey

public PartitionKey(Object... values)

Method Detail

getValues

public List<Object> getValues()

get

public Object get(int index)

Return the value at the specified index in the key.

set

protected void set(int index,
       Object value)

partitionKeyForEntity

public static <E> PartitionKey partitionKeyForEntity(PartitionStrategy strategy,
                                     E entity,
                                     EntityAccessor<E> accessor)

Construct a partition key for the given entity.

This is a convenient way to find the partition that a given entity is written to, or to find a partition using objects from the entity domain.

partitionKeyForEntity

public static <E> PartitionKey partitionKeyForEntity(PartitionStrategy strategy,
                                     E entity,
                                     EntityAccessor<E> accessor,
                                     @Nullable
                                     PartitionKey reuseKey)

Construct a partition key for the given entity, reusing the supplied key if not null.

This is a convenient way to find the partition that a given entity is written to, or to find a partition using objects from the entity domain.

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

getLength

public int getLength()

Return the number of values in the key.

toString

public String toString()

Overrides:

toString in class Object