public interface AtomicMap<K,V> extends Map<K,V>
This allows the entire AtomicMap to be locked when making changes even to certain entries within the map, and also
isolates the map for safe reading (see IsolationLevel
while concurrent writes may be going on.
As a performance optimization, when the map is updated the maps do not replicate all entries to other nodes but only the modifications.
AtomicMaps should be constructed and "registered" with Infinispan using the AtomicMapLookup
helper. This
helper ensures threadsafe construction and registration of AtomicMap instances in Infinispan's data container. E.g.:
AtomicMap<String, Integer> map = AtomicMapLookup.getAtomicMap(cache, "my_atomic_map_key");
Referential Integrity
It is important to note that concurrent readers of an AtomicMap will essentially have the same view of the contents
of the underlying structure, but since AtomicMaps use internal proxies, readers are isolated from concurrent writes
and IsolationLevel.READ_COMMITTED
and IsolationLevel.REPEATABLE_READ
semantics are guaranteed.
However, this guarantee is only present if the values stored in an AtomicMap are immutable (e.g., Strings,
primitives, and other immutable types).
Mutable value objects which happen to be stored in an AtomicMap may be updated and, prior to being committed, or even replaced in the map, be visible to concurrent readers. Hence, AtomicMaps are not suitable for use with mutable value objects.
This interface, for all practical purposes, is just a marker interface that indicates that maps of this type will
be locked atomically in the cache and replicated in a fine grained manner, as it does not add any additional methods
to Map
.
AtomicMapLookup
,
FineGrainedAtomicMap
clear, compute, computeIfAbsent, computeIfPresent, containsKey, containsValue, entrySet, equals, forEach, get, getOrDefault, hashCode, isEmpty, keySet, merge, put, putAll, putIfAbsent, remove, remove, replace, replace, replaceAll, size, values
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