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Subject svn commit: r943315 [2/2] - in /websites/staging/felix/trunk/content: ./ documentation/subprojects/ documentation/subprojects/apache-felix-dependency-manager/guides/ documentation/subprojects/apache-felix-dependency-manager/reference/ documentation/sub...
Date Wed, 11 Mar 2015 09:07:26 GMT
Modified: websites/staging/felix/trunk/content/documentation/subprojects/apache-felix-dependency-manager/reference/thread-model.html
==============================================================================
--- websites/staging/felix/trunk/content/documentation/subprojects/apache-felix-dependency-manager/reference/thread-model.html
(original)
+++ websites/staging/felix/trunk/content/documentation/subprojects/apache-felix-dependency-manager/reference/thread-model.html
Wed Mar 11 09:07:25 2015
@@ -62,14 +62,14 @@
     
     <div class="main">
       <div class="breadcrump" style="font-size: 80%;">
-        <a href="/">Home</a>&nbsp;&raquo&nbsp;<a href="/documentation.html">Documentation</a>&nbsp;&raquo&nbsp;<a
href="/documentation/subprojects.html">Apache Felix Subproject Documentation</a>&nbsp;&raquo&nbsp;<a
href="/documentation/subprojects/apache-felix-dependency-manager.html">Dependency Manager
4</a>
+        <a href="/">Home</a>&nbsp;&raquo&nbsp;<a href="/documentation.html">Documentation</a>&nbsp;&raquo&nbsp;<a
href="/documentation/subprojects.html">Apache Felix Subproject Documentation</a>&nbsp;&raquo&nbsp;<a
href="/documentation/subprojects/apache-felix-dependency-manager.html">Apache Felix Dependency
Manager</a>
       </div>
 
       
       
       <h1>Dependency Manager - Thread Model</h1>
       <p>This section gives a brief overview of the default thread model used by Dependency
Manager, and also explains how to start and handle components concurrently.</p>
-<h1 id="default-thread-model">Default thread model</h1>
+<h2 id="default-thread-model">Default thread model</h2>
 <p>By default, Dependency Manager uses a lock-free/single thread model:</p>
 <ul>
 <li>When an external event that influence the state of a Component is taking place
(for example, when a service dependency on which the Component is depending on is registered
in the 
@@ -86,7 +86,7 @@ then a job (J2) for this new event is ju
 <p>This mechanism allows to serially handle all Component events (service dependencies)
in FIFO order without maintaining any locks.</p>
 <p>The following diagram illustrates the thread model we just described:</p>
 <p><img src="./diagrams/serial-queue.png" alt="Serial Queue" style="width: 600px"/></p>
-<h1 id="enabling-parallelism-with-a-componentexecutorfactory">Enabling parallelism
with a <em>ComponentExecutorFactory</em></h1>
+<h2 id="enabling-parallelism-with-a-componentexecutorfactory">Enabling parallelism
with a <em>ComponentExecutorFactory</em></h2>
 <p>As described above, all the external events that influence the state of a given
component are handed by jobs scheduled in the Serial Queue of the Component, and the jobs
are getting 
 executed serially by a single "master" thread. So usually, bundles are started from a single
thread, meaning that all Components are then activated synchronously.</p>
 <p>But when you register in the OSGi service registry a ComponentExecutorFactory, that
factory will be used by DependencyManager to create an Executor of your choice for each Component,

@@ -102,7 +102,7 @@ is registered (In this way, it is not ne
 <p>Some class name prefixes can also be negated (using "!"), in order to exclude some
components from the list of components using the ComponentExecutorFactory service.</p>
 <p>Notice that if the ComponentExecutorFactory itself and all its dependent services
are defined using the Dependency Manager API, then you have to list the package of such components
with a 
 "!" prefix, in order to indicate that those components must not wait for a ComponentExecutorFactory
service (since they are part of the ComponentExecutorFactory implementation !). </p>
-<h2 id="examples-usage-of-the-orgapachefelixdependencymanagerparallel-property">Examples
usage of the <em>org.apache.felix.dependencymanager.parallel</em> property:</h2>
+<h3 id="examples-usage-of-the-orgapachefelixdependencymanagerparallel-property">Examples
usage of the <em>org.apache.felix.dependencymanager.parallel</em> property:</h3>
 <div class="codehilite"><pre><span class="n">org</span><span class="p">.</span><span
class="n">apache</span><span class="p">.</span><span class="n">felix</span><span
class="p">.</span><span class="n">dependencymanager</span><span class="p">.</span><span
class="n">parallel</span><span class="p">=</span><span class="o">*</span>
  
      <span class="o">-&gt;</span> <span class="n">means</span>
<span class="n">all</span> <span class="n">components</span> <span
class="n">must</span> <span class="n">be</span> <span class="n">cached</span>
<span class="n">until</span> <span class="n">a</span> <span class="n">ComponentExecutorFactory</span>
<span class="n">comes</span> <span class="n">up</span><span class="p">.</span>
 
@@ -117,7 +117,7 @@ is registered (In this way, it is not ne
 </pre></div>
 
 
-<h2 id="examples-of-a-componentexecutorfactory-that-provides-a-shared-threadpool">Examples
of a ComponentExecutorFactory that provides a shared threadpool:</h2>
+<h3 id="examples-of-a-componentexecutorfactory-that-provides-a-shared-threadpool">Examples
of a ComponentExecutorFactory that provides a shared threadpool:</h3>
 <p>First, we define the OSGi bundle context system property to enable parallelism for
all DM Components excepts the one which declares the ComponentExecutorFactory:</p>
 <div class="codehilite"><pre><span class="n">org</span><span class="p">.</span><span
class="n">apache</span><span class="p">.</span><span class="n">felix</span><span
class="p">.</span><span class="n">dependencymanager</span><span class="p">.</span><span
class="n">parallel</span><span class="p">=</span>!<span class="n">com</span><span
class="p">.</span><span class="n">acme</span><span class="p">.</span><span
class="n">management</span><span class="p">.</span><span class="n">threadpool</span><span
class="p">,</span> <span class="o">*</span>
 </pre></div>
@@ -164,7 +164,7 @@ is registered (In this way, it is not ne
 <li><a href="https://svn.apache.org/repos/asf/felix/trunk/dependencymanager/org.apache.felix.dependencymanager.samples/src/org/apache/felix/dependencymanager/samples/tpool/">see
the executor factory</a> sample code and README file to up-to-date informations.</li>
 </ul>
       <div class="timestamp" style="margin-top: 30px; font-size: 80%; text-align: right;">
-        Rev. 1665703 by marrs on Tue, 10 Mar 2015 21:21:26 +0000
+        Rev. 1665812 by marrs on Wed, 11 Mar 2015 09:02:04 +0000
       </div>
       <div class="trademarkFooter"> 
         Apache Felix, Felix, Apache, the Apache feather logo, and the Apache Felix project

Modified: websites/staging/felix/trunk/content/documentation/subprojects/apache-felix-dependency-manager/tutorials/getting-started.html
==============================================================================
--- websites/staging/felix/trunk/content/documentation/subprojects/apache-felix-dependency-manager/tutorials/getting-started.html
(original)
+++ websites/staging/felix/trunk/content/documentation/subprojects/apache-felix-dependency-manager/tutorials/getting-started.html
Wed Mar 11 09:07:25 2015
@@ -62,14 +62,13 @@
     
     <div class="main">
       <div class="breadcrump" style="font-size: 80%;">
-        <a href="/">Home</a>&nbsp;&raquo&nbsp;<a href="/documentation.html">Documentation</a>&nbsp;&raquo&nbsp;<a
href="/documentation/subprojects.html">Apache Felix Subproject Documentation</a>&nbsp;&raquo&nbsp;<a
href="/documentation/subprojects/apache-felix-dependency-manager.html">Dependency Manager
4</a>
+        <a href="/">Home</a>&nbsp;&raquo&nbsp;<a href="/documentation.html">Documentation</a>&nbsp;&raquo&nbsp;<a
href="/documentation/subprojects.html">Apache Felix Subproject Documentation</a>&nbsp;&raquo&nbsp;<a
href="/documentation/subprojects/apache-felix-dependency-manager.html">Apache Felix Dependency
Manager</a>
       </div>
 
       
       
       <h1>Dependency Manager - Getting Started</h1>
-      <h2 id="getting-started">Getting Started</h2>
-<p>When developing an OSGi bundle that has dependencies and possibly registers services,
there are two classes in particular we need to implement:</p>
+      <p>When developing an OSGi bundle that has dependencies and possibly registers
services, there are two classes in particular we need to implement:</p>
 <ol>
 <li>The bundle activator which controls the life-cycle of the bundle.</li>
 <li>The actual component, which can be a POJO.</li>
@@ -77,7 +76,7 @@
 <p>When using the dependency manager, your bundle activator is a subclass of <code>DependencyActivatorBase</code>.
It needs to implement the <code>init</code> life cycle method and can optionally
also implement a <code>destroy</code> method. Both methods take two arguments:
<code>BundleContext</code> and <code>DependencyManager</code>. The
latter is your interface to the declarative API you can use to define your components and
dependencies.</p>
 <p>The following paragraphs will show various examples that explain how to do this.
Subsequently, some more advanced scenarios will be covered that involve listening to dependency
and component state changes and interacting with the OSGi framework from within your component
implementation.</p>
 <p>To use the dependency manager, you should put the <code>org.apache.felix.dependencymanager.jar</code>
in your classpath while compiling and in your OSGi framework when running.</p>
-<h3 id="registering-a-service">Registering a service</h3>
+<h2 id="registering-a-service">Registering a service</h2>
 <p>The first example is about registering a service. We extend <code>DependencyActivatorBase</code>
and in the <code>init</code> method we use the reference to the <code>DependencyManager</code>
to create and add a component. For this component we subsequently set its service interface
and implementation. In this case the interface is the <code>Store</code> interface,
the second parameter, <code>null</code>, allows you to provide properties along
with the service registration. For the implementation, we only mention the <code>Class</code>
of the implementation, which means the dependency manager will lazily instantiate it. In this
case, there is not much point in doing that because the component has no dependencies, but
if it had, the instantiation would only happen when those dependencies were resolved.</p>
 <p>Notice that the dependency manager API uses method chaining to create a more or
less "fluent" API that, with proper indentation, is very easy to read.</p>
 <div class="codehilite"><pre><span class="n">public</span> <span
class="n">class</span> <span class="n">Activator</span> <span class="n">extends</span>
<span class="n">DependencyActivatorBase</span> <span class="p">{</span>
@@ -114,7 +113,7 @@
 </pre></div>
 
 
-<h3 id="depending-on-a-service">Depending on a service</h3>
+<h2 id="depending-on-a-service">Depending on a service</h2>
 <p>Our second example is that of a component that depends on two other services: our
<code>Store</code> from the previous example and the standard OSGi <code>LogService</code>.
Looking at the code, there is a small but important difference between the two: <code>Store</code>
is a required dependency and <code>LogService</code> is not. This means that our
component really needs a store to work, but if there is no logging available, it can work
without. Also note that this component has no <code>setInterface</code> method,
which simply means it is not itself a service. This is perfectly fine.</p>
 <div class="codehilite"><pre><span class="n">public</span> <span
class="n">class</span> <span class="n">Activator</span> <span class="n">extends</span>
<span class="n">DependencyActivatorBase</span> <span class="p">{</span>
     <span class="n">public</span> <span class="n">void</span> <span
class="n">init</span><span class="p">(</span><span class="n">BundleContext</span>
<span class="n">context</span><span class="p">,</span> <span class="n">DependencyManager</span>
<span class="n">manager</span><span class="p">)</span> <span class="n">throws</span>
<span class="n">Exception</span> <span class="p">{</span>
@@ -150,7 +149,7 @@
 </pre></div>
 
 
-<h3 id="tracking-services-with-callbacks">Tracking services with callbacks</h3>
+<h2 id="tracking-services-with-callbacks">Tracking services with callbacks</h2>
 <p>Sometimes, simply injecting services does not give you enough control over a dependency
because you might want to track more than one, or you might want to execute some code on changes.
For all those cases, callbacks are your friends. Since one of our goals is to not introduce
any kind of API in our POJO, callbacks are declared by specifying their method names instead
of through some interface. In this case, we have a dependency on <code>Translator</code>
services, and we define <code>added</code> and <code>removed</code>
as callbacks.</p>
 <div class="codehilite"><pre><span class="n">public</span> <span
class="n">class</span> <span class="n">Activator</span> <span class="n">extends</span>
<span class="n">DependencyActivatorBase</span> <span class="p">{</span>
     <span class="n">public</span> <span class="n">void</span> <span
class="n">init</span><span class="p">(</span><span class="n">BundleContext</span>
<span class="n">context</span><span class="p">,</span> <span class="n">DependencyManager</span>
<span class="n">manager</span><span class="p">)</span> <span class="n">throws</span>
<span class="n">Exception</span> <span class="p">{</span>
@@ -199,7 +198,7 @@
 </pre></div>
 
 
-<h3 id="depending-on-a-configuration">Depending on a configuration</h3>
+<h2 id="depending-on-a-configuration">Depending on a configuration</h2>
 <p>Not all dependencies are on services. There are several other types of dependencies
that are supported, one of them is the configuration dependency. In fact, only <em>required</em>
configuration dependencies are supported, because optional ones can just be achieved by registering
as a <code>ManagedService</code> yourself. When defining the dependency, you must
define the persistent ID of the service. The component will not become active until the configuration
you depend on is available <em>and</em> is valid. The latter can be checked by
your implementation as we will see below.</p>
 <div class="codehilite"><pre><span class="n">public</span> <span
class="n">class</span> <span class="n">Activator</span> <span class="n">extends</span>
<span class="n">DependencyActivatorBase</span> <span class="p">{</span>
     <span class="n">public</span> <span class="n">void</span> <span
class="n">init</span><span class="p">(</span><span class="n">BundleContext</span>
<span class="n">context</span><span class="p">,</span> <span class="n">DependencyManager</span>
<span class="n">manager</span><span class="p">)</span> <span class="n">throws</span>
<span class="n">Exception</span> <span class="p">{</span>
@@ -233,7 +232,7 @@
 <span class="p">}</span>
 </pre></div>
       <div class="timestamp" style="margin-top: 30px; font-size: 80%; text-align: right;">
-        Rev. 1665705 by marrs on Tue, 10 Mar 2015 21:24:23 +0000
+        Rev. 1665812 by marrs on Wed, 11 Mar 2015 09:02:04 +0000
       </div>
       <div class="trademarkFooter"> 
         Apache Felix, Felix, Apache, the Apache feather logo, and the Apache Felix project

Modified: websites/staging/felix/trunk/content/documentation/subprojects/apache-felix-dependency-manager/tutorials/leveraging-the-shell.html
==============================================================================
--- websites/staging/felix/trunk/content/documentation/subprojects/apache-felix-dependency-manager/tutorials/leveraging-the-shell.html
(original)
+++ websites/staging/felix/trunk/content/documentation/subprojects/apache-felix-dependency-manager/tutorials/leveraging-the-shell.html
Wed Mar 11 09:07:25 2015
@@ -62,14 +62,13 @@
     
     <div class="main">
       <div class="breadcrump" style="font-size: 80%;">
-        <a href="/">Home</a>&nbsp;&raquo&nbsp;<a href="/documentation.html">Documentation</a>&nbsp;&raquo&nbsp;<a
href="/documentation/subprojects.html">Apache Felix Subproject Documentation</a>&nbsp;&raquo&nbsp;<a
href="/documentation/subprojects/apache-felix-dependency-manager.html">Dependency Manager
4</a>
+        <a href="/">Home</a>&nbsp;&raquo&nbsp;<a href="/documentation.html">Documentation</a>&nbsp;&raquo&nbsp;<a
href="/documentation/subprojects.html">Apache Felix Subproject Documentation</a>&nbsp;&raquo&nbsp;<a
href="/documentation/subprojects/apache-felix-dependency-manager.html">Apache Felix Dependency
Manager</a>
       </div>
 
       
       
       <h1>Dependency Manager - Leveraging the shell</h1>
-      <h1 id="introduction">Introduction</h1>
-<p>The shell bundle for the dependency manager extends the gogo shell with one new
command called "dm". This command can be used to get insight in the actual components and
services in a running OSGi framework.</p>
+      <p>The shell bundle for the dependency manager extends the gogo shell with one
new command called "dm". This command can be used to get insight in the actual components
and services in a running OSGi framework.</p>
 <p>Typing help <code>help dm</code> in the gogo shell gives an overview
of the available command options.</p>
 <div class="codehilite"><pre><span class="n">dm</span> <span class="o">-</span>
<span class="n">List</span> <span class="n">dependency</span> <span
class="n">manager</span> <span class="n">components</span>
    <span class="n">scope</span><span class="p">:</span> <span
class="n">dependencymanager</span>
@@ -97,7 +96,7 @@
 </pre></div>
 
 
-<h1 id="usage-examples">Usage examples</h1>
+<h2 id="usage-examples">Usage examples</h2>
 <p>Below are some examples for typical usage of the dependency manager shell commands.
The examples are based on a simple component model with a dashboard which has a required dependency
on four probes (temperature, humidity, radiation, pressure). The radiation probe requires
a Sensor service but this sensor is not available.</p>
 <p><strong>List all dependency manager components</strong></p>
 <p><code>dm</code></p>
@@ -157,7 +156,7 @@ The following service(s) are missing:
 
 <p><code>wtf</code> gives the root cause for components not being registered
and therefore their services not being available. In a typical application components have
dependencies on services implemented by components that have dependencies on services etcetera.
This transitivity means that an entire chain of components could be unregistered due to a
(few) root dependencies not being satisfied. <code>wtf</code> is about discovering
those dependencies.</p>
       <div class="timestamp" style="margin-top: 30px; font-size: 80%; text-align: right;">
-        Rev. 1665705 by marrs on Tue, 10 Mar 2015 21:24:23 +0000
+        Rev. 1665812 by marrs on Wed, 11 Mar 2015 09:02:04 +0000
       </div>
       <div class="trademarkFooter"> 
         Apache Felix, Felix, Apache, the Apache feather logo, and the Apache Felix project



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