org.onosproject.store.service

Interface AsyncConsistentMap<K,V>

public interface AsyncConsistentMap<K,V>

A distributed, strongly consistent map whose methods are all executed asynchronously.

This map offers strong read-after-update (where update == create/update/delete) consistency. All operations to the map are serialized and applied in a consistent manner.

The stronger consistency comes at the expense of availability in the event of a network partition. A network partition can be either due to a temporary disruption in network connectivity between participating nodes or due to a node being temporarily down.

All values stored in this map are versioned and the API supports optimistic concurrency by allowing conditional updates that take into consideration the version or value that was previously read.

This map does not allow null values. All methods can throw a ConsistentMapException (which extends RuntimeException) to indicate failures.

Method Summary

Modifier and Type	Method and Description
CompletableFuture<Void>	clear() Removes all of the mappings from this map (optional operation).
CompletableFuture<Versioned<V>>	compute(K key, java.util.function.BiFunction<? super K,? super V,? extends V> remappingFunction) Attempts to compute a mapping for the specified key and its current mapped value (or null if there is no current mapping).
CompletableFuture<Versioned<V>>	computeIf(K key, java.util.function.Predicate<? super V> condition, java.util.function.BiFunction<? super K,? super V,? extends V> remappingFunction) If the value for the specified key satisfies a condition, attempts to compute a new mapping given the key and its current mapped value.
CompletableFuture<Versioned<V>>	computeIfAbsent(K key, java.util.function.Function<? super K,? extends V> mappingFunction) If the specified key is not already associated with a value (or is mapped to null), attempts to compute its value using the given mapping function and enters it into this map unless null.
CompletableFuture<Versioned<V>>	computeIfPresent(K key, java.util.function.BiFunction<? super K,? super V,? extends V> remappingFunction) If the value for the specified key is present and non-null, attempts to compute a new mapping given the key and its current mapped value.
CompletableFuture<Boolean>	containsKey(K key) Returns true if this map contains a mapping for the specified key.
CompletableFuture<Boolean>	containsValue(V value) Returns true if this map contains the specified value.
CompletableFuture<Set<Map.Entry<K,Versioned<V>>>>	entrySet() Returns the set of entries contained in this map.
CompletableFuture<Versioned<V>>	get(K key) Returns the value (and version) to which the specified key is mapped, or null if this map contains no mapping for the key.
CompletableFuture<Boolean>	isEmpty() Returns true if the map is empty.
CompletableFuture<Set<K>>	keySet() Returns a Set view of the keys contained in this map.
CompletableFuture<Versioned<V>>	put(K key, V value) Associates the specified value with the specified key in this map (optional operation).
CompletableFuture<Versioned<V>>	putAndGet(K key, V value) Associates the specified value with the specified key in this map (optional operation).
CompletableFuture<Versioned<V>>	putIfAbsent(K key, V value) If the specified key is not already associated with a value associates it with the given value and returns null, else returns the current value.
CompletableFuture<Optional<Versioned<V>>>	putIfAbsentAndGet(K key, V value) Associates the specified value with the specified key in this map (optional operation).
CompletableFuture<Versioned<V>>	remove(K key) Removes the mapping for a key from this map if it is present (optional operation).
CompletableFuture<Boolean>	remove(K key, long version) Removes the entry for the specified key only if its current version in the map is equal to the specified version.
CompletableFuture<Boolean>	remove(K key, V value) Removes the entry for the specified key only if it is currently mapped to the specified value.
CompletableFuture<Boolean>	replace(K key, long oldVersion, V newValue) Replaces the entry for the specified key only if it is currently mapped to the specified version.
CompletableFuture<Boolean>	replace(K key, V oldValue, V newValue) Replaces the entry for the specified key only if currently mapped to the specified value.
CompletableFuture<Optional<Versioned<V>>>	replaceAndGet(K key, long oldVersion, V newValue) Replaces the entry for the specified key only if it is currently mapped to the specified version.
CompletableFuture<Integer>	size() Returns the number of entries in the map.
CompletableFuture<Collection<Versioned<V>>>	values() Returns the collection of values (and associated versions) contained in this map.

Method Detail

size

CompletableFuture<Integer> size()

Returns the number of entries in the map.

Returns:

a future for map size.

isEmpty

CompletableFuture<Boolean> isEmpty()

Returns true if the map is empty.

Returns:

a future whose value will be true if map has no entries, false otherwise.

containsKey

CompletableFuture<Boolean> containsKey(K key)

Returns true if this map contains a mapping for the specified key.

Parameters:

key - key

Returns:

a future whose value will be true if map contains key, false otherwise.

containsValue

CompletableFuture<Boolean> containsValue(V value)

Returns true if this map contains the specified value.

Parameters:

value - value

Returns:

a future whose value will be true if map contains value, false otherwise.

get

CompletableFuture<Versioned<V>> get(K key)

Returns the value (and version) to which the specified key is mapped, or null if this map contains no mapping for the key.

Parameters:

key - the key whose associated value (and version) is to be returned

Returns:

a future value (and version) to which the specified key is mapped, or null if this map contains no mapping for the key

computeIfAbsent

CompletableFuture<Versioned<V>> computeIfAbsent(K key,
                                                java.util.function.Function<? super K,? extends V> mappingFunction)

If the specified key is not already associated with a value (or is mapped to null), attempts to compute its value using the given mapping function and enters it into this map unless null. If a conflicting concurrent modification attempt is detected, the returned future will be completed exceptionally with ConsistentMapException.ConcurrentModification.

Parameters:

key - key with which the specified value is to be associated

mappingFunction - the function to compute a value

Returns:

the current (existing or computed) value associated with the specified key, or null if the computed value is null

computeIfPresent

CompletableFuture<Versioned<V>> computeIfPresent(K key,
                                                 java.util.function.BiFunction<? super K,? super V,? extends V> remappingFunction)

If the value for the specified key is present and non-null, attempts to compute a new mapping given the key and its current mapped value. If the computed value is null, the current mapping will be removed from the map. If a conflicting concurrent modification attempt is detected, the returned future will be completed exceptionally with ConsistentMapException.ConcurrentModification.

Parameters:

key - key with which the specified value is to be associated

remappingFunction - the function to compute a value

Returns:

the new value associated with the specified key, or null if computed value is null

compute

CompletableFuture<Versioned<V>> compute(K key,
                                        java.util.function.BiFunction<? super K,? super V,? extends V> remappingFunction)

Attempts to compute a mapping for the specified key and its current mapped value (or null if there is no current mapping). If the computed value is null, the current mapping (if one exists) will be removed from the map. If a conflicting concurrent modification attempt is detected, the returned future will be completed exceptionally with ConsistentMapException.ConcurrentModification.

Parameters:

key - key with which the specified value is to be associated

remappingFunction - the function to compute a value

Returns:

the new value associated with the specified key, or null if computed value is null

computeIf

CompletableFuture<Versioned<V>> computeIf(K key,
                                          java.util.function.Predicate<? super V> condition,
                                          java.util.function.BiFunction<? super K,? super V,? extends V> remappingFunction)

If the value for the specified key satisfies a condition, attempts to compute a new mapping given the key and its current mapped value. If the computed value is null, the current mapping will be removed from the map. If a conflicting concurrent modification attempt is detected, the returned future will be completed exceptionally with ConsistentMapException.ConcurrentModification.

Parameters:

key - key with which the specified value is to be associated

condition - condition that should evaluate to true for the computation to proceed

remappingFunction - the function to compute a value

Returns:

the new value associated with the specified key, or the old value if condition evaluates to false

put

CompletableFuture<Versioned<V>> put(K key,
                                    V value)

Associates the specified value with the specified key in this map (optional operation). If the map previously contained a mapping for the key, the old value is replaced by the specified value.

Parameters:

key - key with which the specified value is to be associated

value - value to be associated with the specified key

Returns:

the previous value (and version) associated with key, or null if there was no mapping for key.

putAndGet

CompletableFuture<Versioned<V>> putAndGet(K key,
                                          V value)

Associates the specified value with the specified key in this map (optional operation). If the map previously contained a mapping for the key, the old value is replaced by the specified value.

Parameters:

key - key with which the specified value is to be associated

value - value to be associated with the specified key

Returns:

new value.

putIfAbsentAndGet

CompletableFuture<Optional<Versioned<V>>> putIfAbsentAndGet(K key,
                                                            V value)

Associates the specified value with the specified key in this map (optional operation). If the map previously contained a mapping for the key, the old value is replaced by the specified value.

Parameters:

key - key with which the specified value is to be associated

value - value to be associated with the specified key

Returns:

optional updated value. Will be empty if update did not happen

remove

CompletableFuture<Versioned<V>> remove(K key)

Removes the mapping for a key from this map if it is present (optional operation).

Parameters:

key - key whose value is to be removed from the map

Returns:

the value (and version) to which this map previously associated the key, or null if the map contained no mapping for the key.

clear

CompletableFuture<Void> clear()

Removes all of the mappings from this map (optional operation). The map will be empty after this call returns.

Returns:

future that will be successfully completed when the map is cleared

keySet

CompletableFuture<Set<K>> keySet()

Returns a Set view of the keys contained in this map. This method differs from the behavior of java.util.Map.keySet() in that what is returned is a unmodifiable snapshot view of the keys in the ConsistentMap. Attempts to modify the returned set, whether direct or via its iterator, result in an UnsupportedOperationException.

Returns:

a set of the keys contained in this map

values

CompletableFuture<Collection<Versioned<V>>> values()

Returns the collection of values (and associated versions) contained in this map. This method differs from the behavior of java.util.Map.values() in that what is returned is a unmodifiable snapshot view of the values in the ConsistentMap. Attempts to modify the returned collection, whether direct or via its iterator, result in an UnsupportedOperationException.

Returns:

a collection of the values (and associated versions) contained in this map

entrySet

CompletableFuture<Set<Map.Entry<K,Versioned<V>>>> entrySet()

Returns the set of entries contained in this map. This method differs from the behavior of java.util.Map.entrySet() in that what is returned is a unmodifiable snapshot view of the entries in the ConsistentMap. Attempts to modify the returned set, whether direct or via its iterator, result in an UnsupportedOperationException.

Returns:

set of entries contained in this map.

putIfAbsent

CompletableFuture<Versioned<V>> putIfAbsent(K key,
                                            V value)

If the specified key is not already associated with a value associates it with the given value and returns null, else returns the current value.

Parameters:

key - key with which the specified value is to be associated

value - value to be associated with the specified key

Returns:

the previous value associated with the specified key or null if key does not already mapped to a value.

remove

CompletableFuture<Boolean> remove(K key,
                                  V value)

Removes the entry for the specified key only if it is currently mapped to the specified value.

Parameters:

key - key with which the specified value is associated

value - value expected to be associated with the specified key

Returns:

true if the value was removed

remove

CompletableFuture<Boolean> remove(K key,
                                  long version)

Removes the entry for the specified key only if its current version in the map is equal to the specified version.

Parameters:

key - key with which the specified version is associated

version - version expected to be associated with the specified key

Returns:

true if the value was removed

replace

CompletableFuture<Boolean> replace(K key,
                                   V oldValue,
                                   V newValue)

Replaces the entry for the specified key only if currently mapped to the specified value.

Parameters:

key - key with which the specified value is associated

oldValue - value expected to be associated with the specified key

newValue - value to be associated with the specified key

Returns:

true if the value was replaced

replace

CompletableFuture<Boolean> replace(K key,
                                   long oldVersion,
                                   V newValue)

Replaces the entry for the specified key only if it is currently mapped to the specified version.

Parameters:

key - key key with which the specified value is associated

oldVersion - version expected to be associated with the specified key

newValue - value to be associated with the specified key

Returns:

true if the value was replaced

replaceAndGet

CompletableFuture<Optional<Versioned<V>>> replaceAndGet(K key,
                                                        long oldVersion,
                                                        V newValue)

Replaces the entry for the specified key only if it is currently mapped to the specified version.

Parameters:

key - key key with which the specified value is associated

oldVersion - version expected to be associated with the specified key

newValue - value to be associated with the specified key

Returns:

optional updated value. Will be empty if update did not happen.