18 Local Storage

The Coherence architecture is modular, allowing almost any piece to be extended or even replaced with a custom implementation. One of the responsibilities of the Coherence system that is completely configurable, extendable and replaceable is local storage. Local storage refers to the data structures that actually store or cache the data that is managed by Coherence. For an object to provide local storage, it must support the same standard collections interface, java.util.Map. When a local storage implementation is used by Coherence to store replicated or distributed data, it is called a backing map, because Coherence is actually backed by that local storage implementation. The other common uses of local storage is in front of a distributed cache and as a backup behind the distributed cache.

Typically, Coherence uses one of the following local storage implementations: