public interface SmartInitializingSingleton
BeanFactory
bootstrap. This interface can be implemented by
singleton beans in order to perform some initialization after the regular
singleton instantiation algorithm, avoiding side effects with accidental early
initialization (e.g. from ListableBeanFactory.getBeansOfType(java.lang.Class<T>)
calls).
In that sense, it is an alternative to InitializingBean
which gets
triggered right at the end of a bean's local construction phase.
This callback variant is somewhat similar to
ContextRefreshedEvent
but doesn't
require an implementation of ApplicationListener
,
with no need to filter context references across a context hierarchy etc.
It also implies a more minimal dependency on just the beans
package
and is being honored by standalone ListableBeanFactory
implementations,
not just in an ApplicationContext
environment.
NOTE: If you intend to start/manage asynchronous tasks, preferably
implement Lifecycle
instead which offers
a richer model for runtime management and allows for phased startup/shutdown.
ConfigurableListableBeanFactory.preInstantiateSingletons()
Modifier and Type | Method and Description |
---|---|
void |
afterSingletonsInstantiated()
Invoked right at the end of the singleton pre-instantiation phase,
with a guarantee that all regular singleton beans have been created
already.
|
void afterSingletonsInstantiated()
ListableBeanFactory.getBeansOfType(java.lang.Class<T>)
calls within
this method won't trigger accidental side effects during bootstrap.
NOTE: This callback won't be triggered for singleton beans
lazily initialized on demand after BeanFactory
bootstrap,
and not for any other bean scope either. Carefully use it for beans
with the intended bootstrap semantics only.