The Cache interface exposes simple methods for adding, retrieving and removing entries, including atomic mechanisms exposed by the JDK's ConcurrentMap interface. Based on the cache mode used, invoking these methods will trigger a number of things to happen, potentially even including replicating an entry to a remote node or looking up an entry from a remote node, or potentially a cache store.
Certain methods exposed in Map have certain limitations when used with Infinispan, such as size(), values(), keySet() and entrySet(). Specifically, these methods are unreliable and only provide a best-effort guess. They do not acquire locks, either local or global, and concurrent modifications, additions and removals will not be considered in the result of any of these calls. Further, they only operate on the local data container, and as such, do not give you a global view of state.
Attempting to perform these operations globally would have large performance impact as well as become a scalability bottleneck. As such, these methods should only be used for informational or debugging purposes only.
Further to simply storing entries, Infinispan's cache API allows you to attach mortality information to data. For example, simply using put(key, value) would create an immortal entry, i.e., an entry that lives in the cache forever, until it is removed (or evicted from memory to prevent running out of memory). If, however, you put data in the cache using put(key, value, lifespan, timeunit), this creates a mortal entry, i.e., an entry that has a fixed lifespan and expires after that lifespan.
In addition to lifespan , Infinispan also supports maxIdle as an additional metric with which to determine expiration. Any combination of lifespans or maxIdles can be used.
See this page for an example of using mortal data with Infinispan.
In addition to the simple Cache interface, Infinispan offers an AdvancedCache interface, geared towards extension authors. The AdvancedCache offers the ability to inject custom interceptors, access certain internal components and to apply flags to alter the default behavior of certain cache methods. The following code snippet depicts how an AdvancedCache can be obtained:
Flags are applied to regular cache methods to alter the behavior of certain methods. For a list of all available flags, and their effects, see the Flag enumeration. Flags are applied using AdvancedCache.withFlags(). This builder method can be used to apply any number of flags to a cache invocation, for example:
The AdvancedCache interface also offers advanced developers a mechanism with which to attach custom interceptors. Custom interceptors allow developers to alter the behavior of the cache API methods, and the AdvancedCache interface allows developers to attach these interceptors programmatically, at run-time. See the AdvancedCache Javadocs for more details.