Lifecycle Management

There is much more to an object’s lifecyle than just allocation via new. In particular, there is an important anti-pattern regarding letting this “escape” from a constructor. This page describes the problem in detail.

In Governator, an object can go through a number of steps in its lifecycle. Annotations are available to define methods for these steps. The steps are:

Allocation (via Guice)
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     v
Pre Configuration
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Configuration
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     V
Set Resources
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     V
Post Construction
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     V
Validation and Warm Up
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     V
  -- application runs until termination, then... --    
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     V
Pre Destroy

Here are the annotations available:

Annotation	Target	Description
@PreConfiguration	Methods	Called prior to Configuration Mapping
Resource/Resources	Classes,Methods,Fields	Called after Configuration Mapping. See JDK Docs for details.
@PostConstruct	Methods	Called after Resource setting
@Min, @Max, etc.	Fields	Processed when LifecycleManager.start() is called. See Field Validation for details.
@WarmUp	Methods	Called when LifecycleManager.start() is called. Executed in parallel in the background. See Warm Up for details.
@PreDestroy	Methods	Called when LifecycleManager.close() is called.