io.atomix.core.map

Interface AsyncDistributedMap<K,V>

All Superinterfaces:

AsyncPrimitive, DistributedPrimitive

All Known Subinterfaces:

AsyncDistributedNavigableMap<K,V>, AsyncDistributedSortedMap<K,V>

public interface AsyncDistributedMap<K,V>
extends AsyncPrimitive

Asynchronous distributed map.

Field Summary

Fields inherited from interface io.atomix.primitive.DistributedPrimitive

DEFAULT_OPERATION_TIMEOUT_MILLIS

Method Summary

Modifier and Type	Method and Description
default CompletableFuture<Void>	addListener(MapEventListener<K,V> listener) Registers the specified listener to be notified whenever the map is updated.
CompletableFuture<Void>	addListener(MapEventListener<K,V> listener, Executor executor) Registers the specified listener to be notified whenever the map is updated.
CompletableFuture<Void>	clear() Removes all of the mappings from this map (optional operation).
CompletableFuture<V>	compute(K key, 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<V>	computeIfAbsent(K key, 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<V>	computeIfPresent(K key, 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 maps one or more keys to the specified value.
AsyncDistributedSet<Map.Entry<K,V>>	entrySet() Returns a Set view of the mappings contained in this map.
CompletableFuture<V>	get(K key) Returns the value to which the specified key is mapped, or null if this map contains no mapping for the key.
CompletableFuture<V>	getOrDefault(K key, V defaultValue) Returns the value to which the specified key is mapped, or defaultValue if this map contains no mapping for the key.
CompletableFuture<Boolean>	isEmpty() Returns true if this map contains no key-value mappings.
AsyncDistributedSet<K>	keySet() Returns a Set view of the keys contained in this map.
CompletableFuture<V>	put(K key, V value) Associates the specified value with the specified key in this map (optional operation).
CompletableFuture<Void>	putAll(Map<? extends K,? extends V> m) Copies all of the mappings from the specified map to this map (optional operation).
CompletableFuture<V>	putIfAbsent(K key, V value) If the specified key is not already associated with a value (or is mapped to null) associates it with the given value and returns null, else returns the current value.
CompletableFuture<V>	remove(K key) Removes the mapping for a key from this map if it is present (optional operation).
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<Void>	removeListener(MapEventListener<K,V> listener) Unregisters the specified listener such that it will no longer receive map change notifications.
CompletableFuture<V>	replace(K key, V value) Replaces the entry for the specified key only if it is currently mapped to some value.
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<Integer>	size() Returns the number of key-value mappings in this map.
default DistributedMap<K,V>	sync() Returns a synchronous wrapper around the asynchronous primitive.
DistributedMap<K,V>	sync(Duration operationTimeout) Returns a synchronous wrapper around the asynchronous primitive.
AsyncDistributedCollection<V>	values() Returns a Collection view of the values contained in this map.

Methods inherited from interface io.atomix.primitive.AsyncPrimitive

close, delete

Methods inherited from interface io.atomix.primitive.DistributedPrimitive

addStateChangeListener, name, protocol, removeStateChangeListener, type

Method Detail

size

CompletableFuture<Integer> size()

Returns the number of key-value mappings in this map. If the map contains more than Integer.MAX_VALUE elements, returns Integer.MAX_VALUE.

Returns:

the number of key-value mappings in this map

isEmpty

CompletableFuture<Boolean> isEmpty()

Returns true if this map contains no key-value mappings.

Returns:

true if this map contains no key-value mappings

containsKey

CompletableFuture<Boolean> containsKey(K key)

Returns true if this map contains a mapping for the specified key. More formally, returns true if and only if this map contains a mapping for a key k such that (key==null ? k==null : key.equals(k)). (There can be at most one such mapping.)

Parameters:

key - key whose presence in this map is to be tested

Returns:

true if this map contains a mapping for the specified key

Throws:

ClassCastException - if the key is of an inappropriate type for this map (optional)

NullPointerException - if the specified key is null and this map does not permit null keys (optional)

containsValue

CompletableFuture<Boolean> containsValue(V value)

Returns true if this map maps one or more keys to the specified value. More formally, returns true if and only if this map contains at least one mapping to a value v such that (value==null ? v==null : value.equals(v)). This operation will probably require time linear in the map size for most implementations of the Map interface.

Parameters:

value - value whose presence in this map is to be tested

Returns:

true if this map maps one or more keys to the specified value

Throws:

ClassCastException - if the value is of an inappropriate type for this map (optional)

NullPointerException - if the specified value is null and this map does not permit null values (optional)

get

CompletableFuture<V> get(K key)

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

More formally, if this map contains a mapping from a key k to a value v such that (key==null ? k==null : key.equals(k)), then this method returns v; otherwise it returns null. (There can be at most one such mapping.)

If this map permits null values, then a return value of null does not necessarily indicate that the map contains no mapping for the key; it's also possible that the map explicitly maps the key to null. The containsKey operation may be used to distinguish these two cases.

Parameters:

key - the key whose associated value is to be returned

Returns:

the value to which the specified key is mapped, or null if this map contains no mapping for the key

Throws:

ClassCastException - if the key is of an inappropriate type for this map (optional)

NullPointerException - if the specified key is null and this map does not permit null keys (optional)

put

CompletableFuture<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. (A map m is said to contain a mapping for a key k if and only if m.containsKey(k) would return true.)

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 key, or null if there was no mapping for key. (A null return can also indicate that the map previously associated null with key, if the implementation supports null values.)

Throws:

UnsupportedOperationException - if the put operation is not supported by this map

ClassCastException - if the class of the specified key or value prevents it from being stored in this map

NullPointerException - if the specified key or value is null and this map does not permit null keys or values

IllegalArgumentException - if some property of the specified key or value prevents it from being stored in this map

remove

CompletableFuture<V> remove(K key)

Removes the mapping for a key from this map if it is present (optional operation). More formally, if this map contains a mapping from key k to value v such that (key==null ? k==null : key.equals(k)), that mapping is removed. (The map can contain at most one such mapping.)

Returns the value to which this map previously associated the key, or null if the map contained no mapping for the key.

If this map permits null values, then a return value of null does not necessarily indicate that the map contained no mapping for the key; it's also possible that the map explicitly mapped the key to null.

The map will not contain a mapping for the specified key once the call returns.

Parameters:

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

Returns:

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

Throws:

UnsupportedOperationException - if the remove operation is not supported by this map

ClassCastException - if the key is of an inappropriate type for this map (optional)

NullPointerException - if the specified key is null and this map does not permit null keys (optional)

putAll

CompletableFuture<Void> putAll(Map<? extends K,? extends V> m)

Copies all of the mappings from the specified map to this map (optional operation). The effect of this call is equivalent to that of calling put(k, v) on this map once for each mapping from key k to value v in the specified map. The behavior of this operation is undefined if the specified map is modified while the operation is in progress.

Parameters:

m - mappings to be stored in this map

Throws:

UnsupportedOperationException - if the putAll operation is not supported by this map

ClassCastException - if the class of a key or value in the specified map prevents it from being stored in this map

NullPointerException - if the specified map is null, or if this map does not permit null keys or values, and the specified map contains null keys or values

IllegalArgumentException - if some property of a key or value in the specified map prevents it from being stored in this map

clear

CompletableFuture<Void> clear()

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

Throws:

UnsupportedOperationException - if the clear operation is not supported by this map

keySet

AsyncDistributedSet<K> keySet()

Returns a Set view of the keys contained in this map. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. If the map is modified while an iteration over the set is in progress (except through the iterator's own remove operation), the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Set.remove, removeAll, retainAll, and clear operations. It does not support the add or addAll operations.

Returns:

a set view of the keys contained in this map

values

AsyncDistributedCollection<V> values()

Returns a Collection view of the values contained in this map. The collection is backed by the map, so changes to the map are reflected in the collection, and vice-versa. If the map is modified while an iteration over the collection is in progress (except through the iterator's own remove operation), the results of the iteration are undefined. The collection supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Collection.remove, removeAll, retainAll and clear operations. It does not support the add or addAll operations.

Returns:

a collection view of the values contained in this map

entrySet

AsyncDistributedSet<Map.Entry<K,V>> entrySet()

Returns a Set view of the mappings contained in this map. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. If the map is modified while an iteration over the set is in progress (except through the iterator's own remove operation, or through the setValue operation on a map entry returned by the iterator) the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Set.remove, removeAll, retainAll and clear operations. It does not support the add or addAll operations.

Returns:

a set view of the mappings contained in this map

getOrDefault

CompletableFuture<V> getOrDefault(K key,
                                  V defaultValue)

Returns the value to which the specified key is mapped, or defaultValue if this map contains no mapping for the key.

Parameters:

key - the key whose associated value is to be returned

defaultValue - the default mapping of the key

Returns:

the value to which the specified key is mapped, or defaultValue if this map contains no mapping for the key

Throws:

ClassCastException - if the key is of an inappropriate type for this map (optional)

NullPointerException - if the specified key is null and this map does not permit null keys (optional)

putIfAbsent

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

If the specified key is not already associated with a value (or is mapped to null) 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 there was no mapping for the key. (A null return can also indicate that the map previously associated null with the key, if the implementation supports null values.)

Throws:

UnsupportedOperationException - if the put operation is not supported by this map (optional)

ClassCastException - if the key or value is of an inappropriate type for this map (optional)

NullPointerException - if the specified key or value is null, and this map does not permit null keys or values (optional)

IllegalArgumentException - if some property of the specified key or value prevents it from being stored in this map (optional)

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

Throws:

UnsupportedOperationException - if the remove operation is not supported by this map (optional)

ClassCastException - if the key or value is of an inappropriate type for this map (optional)

NullPointerException - if the specified key or value is null, and this map does not permit null keys or values (optional)

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

Throws:

UnsupportedOperationException - if the put operation is not supported by this map (optional)

ClassCastException - if the class of a specified key or value prevents it from being stored in this map

NullPointerException - if a specified key or newValue is null, and this map does not permit null keys or values

NullPointerException - if oldValue is null and this map does not permit null values (optional)

IllegalArgumentException - if some property of a specified key or value prevents it from being stored in this map

replace

CompletableFuture<V> replace(K key,
                             V value)

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

Parameters:

key - key with which the specified value is associated

value - value to be associated with the specified key

Returns:

the previous value associated with the specified key, or null if there was no mapping for the key. (A null return can also indicate that the map previously associated null with the key, if the implementation supports null values.)

Throws:

UnsupportedOperationException - if the put operation is not supported by this map (optional)

ClassCastException - if the class of the specified key or value prevents it from being stored in this map (optional)

NullPointerException - if the specified key or value is null, and this map does not permit null keys or values

IllegalArgumentException - if some property of the specified key or value prevents it from being stored in this map

computeIfAbsent

CompletableFuture<V> computeIfAbsent(K key,
                                     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 the function returns null no mapping is recorded. If the function itself throws an (unchecked) exception, the exception is rethrown, and no mapping is recorded. The most common usage is to construct a new object serving as an initial mapped value or memoized result, as in:

 
 map.computeIfAbsent(key, k -> new Value(f(k)));
 

Or to implement a multi-value map, Map<K,Collection<V>>, supporting multiple values per key:

 
 map.computeIfAbsent(key, k -> new HashSet<V>()).add(v);
 

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

Throws:

NullPointerException - if the specified key is null and this map does not support null keys, or the mappingFunction is null

UnsupportedOperationException - if the put operation is not supported by this map (optional)

ClassCastException - if the class of the specified key or value prevents it from being stored in this map (optional)

computeIfPresent

CompletableFuture<V> computeIfPresent(K key,
                                      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 function returns null, the mapping is removed. If the function itself throws an (unchecked) exception, the exception is rethrown, and the current mapping is left unchanged.

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 none

Throws:

NullPointerException - if the specified key is null and this map does not support null keys, or the remappingFunction is null

UnsupportedOperationException - if the put operation is not supported by this map (optional)

ClassCastException - if the class of the specified key or value prevents it from being stored in this map (optional)

compute

CompletableFuture<V> compute(K key,
                             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). For example, to either create or append a String msg to a value mapping:

If the function returns null, the mapping is removed (or remains absent if initially absent). If the function itself throws an (unchecked) exception, the exception is rethrown, and the current mapping is left unchanged.

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 none

Throws:

NullPointerException - if the specified key is null and this map does not support null keys, or the remappingFunction is null

UnsupportedOperationException - if the put operation is not supported by this map (optional)

ClassCastException - if the class of the specified key or value prevents it from being stored in this map (optional)

addListener

default CompletableFuture<Void> addListener(MapEventListener<K,V> listener)

Registers the specified listener to be notified whenever the map is updated.

Parameters:

listener - listener to notify about map events

Returns:

future that will be completed when the operation finishes

addListener

CompletableFuture<Void> addListener(MapEventListener<K,V> listener,
                                    Executor executor)

Registers the specified listener to be notified whenever the map is updated.

Parameters:

listener - listener to notify about map events

executor - executor to use for handling incoming map events

Returns:

future that will be completed when the operation finishes

removeListener

CompletableFuture<Void> removeListener(MapEventListener<K,V> listener)

Unregisters the specified listener such that it will no longer receive map change notifications.

Parameters:

listener - listener to unregister

Returns:

future that will be completed when the operation finishes

sync

default DistributedMap<K,V> sync()

Description copied from interface: AsyncPrimitive

Returns a synchronous wrapper around the asynchronous primitive.

Specified by:

sync in interface AsyncPrimitive

Returns:

the synchronous primitive

sync

DistributedMap<K,V> sync(Duration operationTimeout)

Description copied from interface: AsyncPrimitive

Returns a synchronous wrapper around the asynchronous primitive.

Specified by:

sync in interface AsyncPrimitive

Parameters:

operationTimeout - the synchronous operation timeout

Returns:

the synchronous primitive