Package com.hazelcast.query

Interface PartitionPredicate<K,V>

Type Parameters:

K - type of the entry key

V - type of the entry value

All Superinterfaces:

Predicate<K,V>, Serializable

public interface PartitionPredicate<K,V>
extends Predicate<K,V>

A Predicate that restricts the execution of a Predicate to specific partitions.

This can help to speed up query execution since only a subset of all partitions needs to be queried.

This predicate only has effect if used as an outermost predicate.

See Also:

• Predicates.partitionPredicate(Object, Predicate)

Method Summary

Modifier and Type	Method	Description
Object	getPartitionKey()	Returns a random partition key from the collection.
default Collection<? extends Object>	getPartitionKeys()	Returns the partition keys that determine the partitions the target Predicate is going to execute on.
Predicate<K,V>	getTarget()	Returns the target Predicate.

Methods inherited from interface com.hazelcast.query.Predicate

apply

Method Details

getPartitionKeys

default Collection<? extends Object> getPartitionKeys()

Returns the partition keys that determine the partitions the target Predicate is going to execute on.

A default implementation of partition keys that wraps the partition key in a singleton collection is provided for backwards compatibility.

Returns:

the partition keys

Since:

5.2

getPartitionKey

Object getPartitionKey()

Returns a random partition key from the collection. This is useful for client message routing to cluster instances. If there is a single value in the collection it is always returned as-is to be backwards compatible with older versions of PartitionPredicate.

Returns:

the single key

getTarget

Predicate<K,V> getTarget()

Returns the target Predicate.