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From pde...@apache.org
Subject svn commit: r1525384 - /felix/site/trunk/content/documentation/subprojects/apache-felix-dependency-manager/apache-felix-dependency-manager-using-annotations/dependencymanager-annotations-lifecycle.mdtext
Date Sun, 22 Sep 2013 15:57:38 GMT
Author: pderop
Date: Sun Sep 22 15:57:38 2013
New Revision: 1525384

URL: http://svn.apache.org/r1525384
Log:
CMS migration

Modified:
    felix/site/trunk/content/documentation/subprojects/apache-felix-dependency-manager/apache-felix-dependency-manager-using-annotations/dependencymanager-annotations-lifecycle.mdtext

Modified: felix/site/trunk/content/documentation/subprojects/apache-felix-dependency-manager/apache-felix-dependency-manager-using-annotations/dependencymanager-annotations-lifecycle.mdtext
URL: http://svn.apache.org/viewvc/felix/site/trunk/content/documentation/subprojects/apache-felix-dependency-manager/apache-felix-dependency-manager-using-annotations/dependencymanager-annotations-lifecycle.mdtext?rev=1525384&r1=1525383&r2=1525384&view=diff
==============================================================================
--- felix/site/trunk/content/documentation/subprojects/apache-felix-dependency-manager/apache-felix-dependency-manager-using-annotations/dependencymanager-annotations-lifecycle.mdtext
(original)
+++ felix/site/trunk/content/documentation/subprojects/apache-felix-dependency-manager/apache-felix-dependency-manager-using-annotations/dependencymanager-annotations-lifecycle.mdtext
Sun Sep 22 15:57:38 2013
@@ -2,24 +2,47 @@ translation_pending: true
 Title: Dependency Manager Component Lifecycle
 Excerpt: Dependency Manager component lifecycle
 
-A component has a lifecycle that controls when it is started or stopped. A bundle must be
started before the DM Runtime can process its components. When the bundle is started, the
DM Runtime then parses a specific *DependencyManager-Component* manifest header, which points
to a list of descriptors describing all annotated components. Such descriptors are actually
generated at compilation time, and annotation are not reflectively parsed at runtime. Only
the descriptor is used to process the components. For each component, the DM Runtime first
ensures that all dependencies are satisfied before activating it. Likewise, the component
is deactivated when some of the required dependencies are not available anymore or when the
bundle is stopped. Unless the bundle is stopped, components may be deactivated and reactivated,
depending on the departure and arrival of required dependencies. The manager which is in charge
of maintaining the state of components is implemented in the DM Runtime bun
 dle (org.apache.felix.dm.runtime bundle).
+A component has a lifecycle that controls when it is started or stopped. 
+A bundle must be started before the DM Runtime can process its components. 
+When the bundle is started, the DM Runtime then parses a specific 
+*DependencyManager-Component* manifest header, which points to a list of descriptors 
+describing all annotated components. Such descriptors are actually generated at 
+compilation time, and annotation are not reflectively parsed at runtime. 
+Only the descriptor is used to process the components. 
+
+For each component, the DM Runtime 
+first ensures that all dependencies are satisfied before activating it. Likewise, the 
+component is deactivated when some of the required dependencies are not available anymore

+or when the bundle is stopped. Unless the bundle is stopped, components may be deactivated

+and reactivated, depending on the departure and arrival of required dependencies. The 
+manager which is in charge of maintaining the state of components is implemented in the 
+DM Runtime bundle (org.apache.felix.dm.runtime bundle).
 
 ## Lifecycle Callbacks
 
 ### Component Activation
 
 Activating a component consists of the following steps:
-1. Wait for all required dependencies to be available. When all required dependencies are
available:
-1. * Instantiate the component.
-1. * Inject all required dependencies (on class fields using reflection, or by invoking callback
methods).
-1. * Inject all optional dependencies defined on class fields, *possibly with a NullObject*
if the dependency is not available.
-1. * Call the component init method (annotated with *@Init*). In the  Init method, you are
yet allowed to add some additional dependencies  (but using the API). Alternatively, you can
also configure some  dependencies dynamically (explained later, in [#Dynamic Dependency Configuration]({{
refs.-dynamic-dependency-configuration.path }})).
-1. Wait for extra dependencies optionally configured from the init() method.
-1. If the component is not using the @*LifecycleController* annotation (detailed in the [#Controlling
the Lifecycle]({{ refs.-controlling-the-lifecycle.path }}) section), then:
-1. * Invoke the component start method (annotated with *@Start*).
-1. * Publish some OSGi services (if the component provides some services).
-1. * Start tracking optional dependencies applied on method callbacks (useful for the whiteboard
pattern). *Notice that NullObject pattern is not applied to optional callback dependencies*.
In other words, if the dependency is not there, your callback won't be invoked at all. If
you need the NullObject pattern, then apply optional dependencies on class fields, not on
callback methods.
-1. Else do nothing because  the component will trigger itself the startup using
the lifecycle controller.
+
+ 1. Wait for all required dependencies to be available. When all required dependencies are
available:
+
+- Instantiate the component.
+- Inject all required dependencies (on class fields using reflection, or by invoking 
+callback methods).
+- Inject all optional dependencies defined on class fields, possibly with a *NullObject*
if the dependency is not available.
+- Call the component init method (annotated with *@Init*). In the  Init method, you are 
+yet allowed to add some additional dependencies  (but using the API). 
+Alternatively, you can also configure some  dependencies dynamically 
+(explained later, in [#Dynamic Dependency Configuration](#dynamic-dependency-configuration).
+ 1. Wait for extra dependencies optionally configured from the init() method.
+ 1. If the component is not using the @*LifecycleController* annotation (detailed in the

+[#Controlling the Lifecycle](#controlling-the-lifecycle.path) section), then:
+
+- Invoke the component start method (annotated with *@Start*).
+- Publish some OSGi services (if the component provides some services).
+- Start tracking optional dependencies applied on method callbacks (useful for the whiteboard
pattern). *Notice that NullObject pattern is not applied to optional callback dependencies*.
In other words, if the dependency is not there, your callback won't be invoked at all. If
you need the NullObject pattern, then apply optional dependencies on class fields, not on
callback methods.
+
+ 1. Else do nothing because  the component will trigger itself the startup using
the lifecycle controller.
 
 ### Component Deactivation
 
@@ -57,13 +80,8 @@ The following example shows a basic comp
         }
     }
 
-
-### 
-
-
 ### Dynamic Dependency Configuration
 
-
 #### Rationale
 
 We have seen that a component may declare some dependencies and is  started when all required
dependencies are available. But there are some  cases when you may need to define some dependencies
filters  dynamically, possibly from data picked up from other  dependencies (like a configuration
dependency for instance).



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