This section details the usage of Smacks implementation of Entity Capabilities.
XEP related: XEP-0115: Entity Capabilities
Description
Entity Capabilities is a XMPP Protocol extension, which, in order to minimize network impact, caches the capabilities of XMPP entities. Those capabilities are determined with the help of the Service Discovery Protocol (XEP-0030).
Usage
Entity Capabilities work silenty in background when enabled. If the remote XMPP entity does not support XEP-0115 but XEP-0030 then XEP-0030 mechanisms are transparently used. You can enable or disable Entity Capabilities by using EntityCapsManager.
The cache used by Smack for Entity Capabilities is non-persistent as default. That is, the cache only uses memory. But it is also possible to set a persistent Entity Capabilities cache, which is recommended.
Examples
Enable Entity Capabilities
// Get an instance of entity caps manager for the specified connection
EntityCapsManager mgr = EntityCapsManager.getInstanceFor(connection);
// Enable entity capabilities
mgr.enableEntityCaps();
Configure a persistent cache for Entity Capabilities
// Get an instance of entity caps manager for the specified connection
EntityCapsManager mgr = EntityCapsManager.getInstanceFor(connection);
// Create an cache, see smackx.entitycaps.cache for pre-defined cache implementations
EntityCapsPersistentCache cache = new SimpleDirectoryPersistentCache(new File("/foo/cachedir"));
// Set the cache
mgr.setPersistentCache(cache);