JCache Configuration

Hazelcast JCache provides two different ways of cache configuration:

  • programmatically: the typical Hazelcast way, using the Config API seen above,
  • and declaratively: using hazelcast.xml or hazelcast-client.xml.

JCache Declarative Configuration

You can declare your JCache cache configuration using the hazelcast.xml or hazelcast-client.xml configuration files. Using this declarative configuration makes the creation of the javax.cache.Cache fully transparent and automatically ensures internal thread safety. You do not need a call to javax.cache.Cache::createCache in this case: you can retrieve the cache using javax.cache.Cache::getCache overloads and by passing in the name defined in the configuration for the cache.

To retrieve the cache defined in the declaration files, you need only perform a simple call (example below) because the cache is created automatically by the implementation.

CachingProvider cachingProvider = Caching.getCachingProvider();
CacheManager cacheManager = cachingProvider.getCacheManager();
Cache<Object, Object> cache = cacheManager
    .getCache( "default", Object.class, Object.class );

Note that this section only describes the JCache provided standard properties. For the Hazelcast specific properties, please see the ICache Configuration section.

<cache name="default">
  <key-type class-name="java.lang.Object" />
  <value-type class-name="java.lang.Object" />
  <statistics-enabled>false</statistics-enabled>
  <management-enabled>false</management-enabled>

  <read-through>true</read-through>
  <write-through>true</write-through>
  <cache-loader-factory
     class-name="com.example.cache.MyCacheLoaderFactory" />
  <cache-writer-factory
     class-name="com.example.cache.MyCacheWriterFactory" />
  <expiry-policy-factory
     class-name="com.example.cache.MyExpirePolicyFactory" />

  <cache-entry-listeners>
    <cache-entry-listener old-value-required="false" synchronous="false">
      <cache-entry-listener-factory
         class-name="com.example.cache.MyEntryListenerFactory" />
      <cache-entry-event-filter-factory
         class-name="com.example.cache.MyEntryEventFilterFactory" />
    </cache-entry-listener>
    ...
  </cache-entry-listeners>
</cache>
  • key-type#class-name: The fully qualified class name of the cache key type, defaults to java.lang.Object.
  • value-type#class-name: The fully qualified class name of the cache value type, defaults to java.lang.Object.
  • statistics-enabled: If set to true, statistics like cache hits and misses are collected. Its default value is false.
  • management-enabled: If set to true, JMX beans are enabled and collected statistics are provided - It doesn't automatically enables statistics collection, defaults to false.
  • read-through: If set to true, enables read-through behavior of the cache to an underlying configured javax.cache.integration.CacheLoader which is also known as lazy-loading, defaults to false.
  • write-through: If set to true, enables write-through behavior of the cache to an underlying configured javax.cache.integration.CacheWriter which passes any changed value to the external backend resource, defaults to false.
  • cache-loader-factory#class-name: The fully qualified class name of the javax.cache.configuration.Factory implementation providing a javax.cache.integration.CacheLoader instance to the cache.
  • cache-writer-factory#class-name: The fully qualified class name of the javax.cache.configuration.Factory implementation providing a javax.cache.integration.CacheWriter instance to the cache.
  • expiry-policy-factory#-class-name: The fully qualified class name of the javax.cache.configuration.Factory implementation providing a javax.cache.expiry.ExpiryPolicy instance to the cache.
  • cache-entry-listener: A set of attributes and elements, explained below, to describe a javax.cache.event. CacheEntryListener.
    • cache-entry-listener#old-value-required: If set to true, previously assigned values for the affected keys will be sent to the javax.cache.event.CacheEntryListener implementation. Setting this attribute to true creates additional traffic, defaults to false.
    • cache-entry-listener#synchronous: If set to true, the javax.cache.event.CacheEntryListener implementation will be called in a synchronous manner, defaults to false.
    • cache-entry-listener/entry-listener-factory#class-name: The fully qualified class name of the javax.cache.configuration.Factory implementation providing a javax.cache.event.CacheEntryListener instance.
    • cache-entry-listener/entry-event-filter-factory#class-name: The fully qualified class name of the javax.cache.configuration.Factory implementation providing a javax.cache.event. CacheEntryEventFilter instance.



image NOTE: The JMX MBeans provided by Hazelcast JCache show statistics of the local node only. To show the cluster-wide statistics, the user should collect statistic information from all nodes and accumulate them to the overall statistics.

JCache Programmatic Configuration

To configure the JCache programmatically:

  • either instantiate javax.cache.configuration.MutableConfiguration if you will use only the JCache standard configuration,
  • or instantiate com.hazelcast.config.CacheConfig for a deeper Hazelcast integration.

com.hazelcast.config.CacheConfig offers additional options that are specific to Hazelcast like asynchronous and synchronous backup counts. Both classes share the same supertype interface javax.cache.configuration. CompleteConfiguration which is part of the JCache standard.



image NOTE: To stay vendor independent, try to keep your code as near as possible to the standard JCache API. We recommend you to use declarative configuration and use the javax.cache.configuration.Configuration or javax.cache.configuration.CompleteConfiguration interfaces in your code only when you need to pass the configuration instance throughout your code.

If you don't need to configure Hazelcast specific properties, it is recommended that you instantiate javax.cache.configuration.MutableConfiguration and that you use the setters to configure Hazelcast as shown in the example in the Quick Example section. Since the configurable properties are the same as the ones explained in the JCache Declarative Configuration section, they are not mentioned here. For Hazelcast specific properties, please read the ICache Configuration section section.