Hazelcast provides a very nice set of features for distributed caching (which is what we use it for with L2 caching) plus "Data grid" features.

My expectation is that most people will prefer client/server mode with use of near caches.

Client/server mode

We can use Hazelcast in client/server mode which means that our application uses a Hazelcast client to talk to a Hazelcast cluster (of servers).

In this mode the bean cache data is partitioned across all the Hazelcast servers in the cluster and not in our application. We can choose to use a near cache for some or all of our bean types and in doing so improve performance (by having local data) but increase memory footprint in our application (as it now holds some cache data).


For client/server mode the configuration file should be a hazelcast-client.xml

Server mode

In server mode our application starts a Hazelcast server instance which is a full fledged member of the Hazelcast cluster. This means that it will hold data etc.


For server mode the configuration file should be a hazelcast.xml.


Add a dependency to ebean-hazelcast. When Ebean starts ebean-hazelcast is automatically registered as the L2 cache implementation.

Disable L2 cache

During development and testing it is often useful to disable the use of the l2 cache.

## disable use of L2 cache (for dev / testing etc)


XML configuration

Hazelcast will operate without any configuration but typically you will want to add a hazelcast-client.xml or hazelcast.xml configuration for client/server or server mode respectively.

In hazelcast-client.xml you can specify the use of near cache for example which is a common need.

Programmatic configuration

You can programmatically configure Hazelcast by creating an instance of Hazelcast ClientConfig or Config and setting it via:

ClientConfig configuration = ...;
serverConfig.setServiceObject("hazelcastConfiguration", configuration);

If this configuration instance is passed in Ebean will use it to configure a Hazelcast client or server instance. Otherwise it will use default configuration and Hazelcast will automatically search for and use the xml configuration files.

Getting started

  • Annotate beans with @Cache
  • Add maven dependency ebean-hazelcast
  • Optionally add hazelcast-client.xml or hazelcast.xml
  • For client/server mode you need a running Hazelcast server