Reference Manual 3.9-SNAPSHOT

Hazelcast JCache Hazelcast JCache Extension-ICache Configuring ICache

As mentioned in the JCache Declarative Configuration section, the Hazelcast ICache extension offers additional configuration properties over the default JCache configuration. These additional properties include internal storage format, backup counts, eviction policy and quorum reference.

The declarative configuration for ICache is a superset of the previously discussed JCache configuration:

<cache>
  <!-- ... default cache configuration goes here ... -->
  <backup-count>1</backup-count>
  <async-backup-count>1</async-backup-count>
  <in-memory-format>BINARY</in-memory-format>
  <eviction size="10000" max-size-policy="ENTRY_COUNT" eviction-policy="LRU" />
  <partition-lost-listeners>
     <partition-lost-listener>CachePartitionLostListenerImpl</partition-lost-listener>
 </partition-lost-listeners>
 <quorum-ref>quorum-name</quorum-ref>
 <disable-per-entry-invalidation-events>true</disable-per-entry-invalidation-events>
</cache>
  • backup-count: Number of synchronous backups. Those backups are executed before the mutating cache operation is finished. The mutating operation is blocked. backup-count default value is 1.
  • async-backup-count: Number of asynchronous backups. Those backups are executed asynchronously so the mutating operation is not blocked and it will be done immediately. async-backup-count default value is 0.
  • in-memory-format: Internal storage format. For more information, please see the In Memory Format section. Default is BINARY.
  • eviction: Defines the used eviction strategies and sizes for the cache. For more information on eviction, please see the JCache Eviction.
    • size: Maximum number of records or maximum size in bytes depending on the max-size-policy property. Size can be any integer between 0 and Integer.MAX_VALUE. Default max-size-policy is ENTRY_COUNT and default size is 10.000.
    • max-size-policy: Maximum size. If maximum size is reached, the cache is evicted based on the eviction policy. Default max-size-policy is ENTRY_COUNT and default size is 10.000. The following eviction policies are available:
      • ENTRY_COUNT: Maximum number of cache entries in the cache. Available on heap based cache record store only.
      • USED_NATIVE_MEMORY_SIZE: Maximum used native memory size in megabytes per cache for each Hazelcast instance. Available on High-Density Memory cache record store only.
      • USED_NATIVE_MEMORY_PERCENTAGE: Maximum used native memory size percentage per cache for each Hazelcast instance. Available on High-Density Memory cache record store only.
      • FREE_NATIVE_MEMORY_SIZE: Minimum free native memory size in megabytes for each Hazelcast instance. Available on High-Density Memory cache record store only.
      • FREE_NATIVE_MEMORY_PERCENTAGE: Minimum free native memory size percentage for each Hazelcast instance. Available on High-Density Memory cache record store only.
    • eviction-policy: Eviction policy that compares values to find the best matching eviction candidate. Default is LRU.
      • LRU: Less Recently Used - finds the best eviction candidate based on the lastAccessTime.
      • LFU: Less Frequently Used - finds the best eviction candidate based on the number of hits.
  • partition-lost-listeners : Defines listeners for dispatching partition lost events for the cache. For more information, please see the ICache Partition Lost Listener section.
  • quorum-ref : Name of quorum configuration that you want this cache to use.
  • disable-per-entry-invalidation-events : Disables invalidation events for each entry; but full-flush invalidation events are still enabled. Full-flush invalidation means the invalidation of events for all entries when clear is called. The default value is false.

Since javax.cache.configuration.MutableConfiguration misses the above additional configuration properties, Hazelcast ICache extension provides an extended configuration class called com.hazelcast.config.CacheConfig. This class is an implementation of javax.cache.configuration.CompleteConfiguration and all the properties shown above can be configured using its corresponding setter methods.



image NOTE: At the client side, ICache can be configured only programmatically.