Bean cache

To enable bean caching we add the @Cache annotation to the entity bean type.

@Cache
@Entity
public class Customer {
 ...
}

Natural key

We use the naturalKey attribute to define a natural unique key that can be used.

Ebean will then automatically maintain a natural key lookup cache and use this with queries that use the natural key properties in where expressions.

@Cache(naturalKey = "email")

// Multiple properties make up the unique natural key
@Cache(naturalKey = {"store","sku"})

Used implicitly

If @Cache has been defined on the bean then Ebean will automatically try and use the L2 bean cache.

@Cache
@Entity
public class Country

// automatically use the cache
Country country = DB.find(Country.class,"NZ");

// references automatically use the cache too
Country countryRef = DB.reference(Country.class,"NZ");

// hit the country cache automatically via navigation
// ... and lazy loading
Customer customer = DB.find(Customer.class, 1);
Address billingAddress = customer.getBillingAddress();
Country c2 = billingAddress.getCountry();

Explicitly

We can explicitly specify to use the bean cache via query.setUseCache() and for the bean cache we can say when we do not want to use the cache.

// explicitly state we do not want to use the bean cache
Customer customer = DB.find(Customer.class)
  .setUseCache(false)
  .setId(7)
  .findOne();

Near cache

To enable near caching when using ebean-redis set nearCache=true. To enable near caching with Hazelcast or Ignite we instead use their Hazelcast | Ignite specific configuration.

@Cache(nearCache=true)
@Entity
public class Country

With the above, when using ebean-redis a query hitting the bean cache will first try the in-process near cache and only hit Redis when the data isn't in the local near cache.