Hazelcast JCache provides for two different methods of cache configuration:
- programmatically: the typical Hazelcast way, using the Config API seen above, and
- declaratively: using
hazelcast.xml
orhazelcast-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 creating 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 that you 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
: Fully qualified class name of the cache key type. Its default value isjava.lang.Object
. -
value-type#class-name
: Fully qualified class name of the cache value type. Its default value isjava.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 enable statistics collection. Defaults to false. -
read-through
: If set to true, enables read-through behavior of the cache to an underlying configuredjavax.cache.integration.CacheLoader
which is also known as lazy-loading. Its default value is false. -
write-through
: If set to true, enables write-through behavior of the cache to an underlying configuredjavax.cache.integration.CacheWriter
which passes any changed value to the external backend resource. Its default value is false. -
cache-loader-factory#class-name
: Fully qualified class name of thejavax.cache.configuration.Factory
implementation providing ajavax.cache.integration.CacheLoader
instance to the cache. -
cache-writer-factory#class-name
: Fully qualified class name of thejavax.cache.configuration.Factory
implementation providing ajavax.cache.integration.CacheWriter
instance to the cache. -
expiry-policy-factory#-class-name
: Fully qualified class name of thejavax.cache.configuration.Factory
implementation providing ajavax.cache.expiry.ExpiryPolicy
instance to the cache. -
cache-entry-listener
: A set of attributes and elements, explained below, to describe ajavax.cache.event. CacheEntryListener
.-
cache-entry-listener#old-value-required
: If set to true, previously assigned values for the affected keys will be sent to thejavax.cache.event.CacheEntryListener
implementation. Setting this attribute to true creates additional traffic. Its default value is false. -
cache-entry-listener#synchronous
: If set to true, thejavax.cache.event.CacheEntryListener
implementation will be called in a synchronous manner. Its default value is false. -
cache-entry-listener/entry-listener-factory#class-name
: Fully qualified class name of thejavax.cache.configuration.Factory
implementation providing ajavax.cache.event.CacheEntryListener
instance. -
cache-entry-listener/entry-event-filter-factory#class-name
: Fully qualified class name of thejavax.cache.configuration.Factory
implementation providing ajavax.cache.event. CacheEntryEventFilter
instance.
-
NOTE: The JMX MBeans provided by Hazelcast JCache show statistics of the local member only. To show the cluster-wide statistics, the user should collect statistic information from all members 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, such as asynchronous and synchronous backup counts.
Both classes share the same supertype interface javax.cache.configuration. CompleteConfiguration
which is part of the JCache
standard.
NOTE: To stay vendor independent, try to keep your code as near as possible to the standard JCache API. We recommend that you use declarative configuration
and that you 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, we recommend that you instantiate
javax.cache.configuration.MutableConfiguration
and that you use the setters to configure Hazelcast as shown in the example in the
Example JCache Application 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.