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                 <h1>CDI events: loose coupling and extensibility</h1>
 <p>CDI allows you to extend business code by the Notifier/Observer pattern.</p>
 <p>To do it you simply inject a field <code>Event</code> in the notifier class. This class is a template and the parameter type is the object type to fire. Then when you want to notify observers you simply call the method fire of the event object passing as a parameter the event itself<br/>(your own class!).</p>
 <p>On the other side you annotated a method parameter <code>@Observes</code> and the parameter type is the sent type by the notifier.</p>
 <p>Note: of course you can add qualifiers to be more precise on your events.</p>
 <h1>The example</h1>
 <p>The example is pretty simple: an ejb uses the <code>@Schedule</code> annotation to get a notification each second. The each second this EJB will send the current date through CDI events.</p>
 <p>This is our "business" code. It is a simple behavior (nothing).</p>
 <p>In our test (which is considered as an extension) we created an observer (<code>Observer</code> class) which simply store and log each received date.</p>
 <p>The test itself (<code>EventTest</code>) simply verifies the dates were received.</p>
 <h1>Conclusion</h1>
 <p>CDI let's implement very easily plugins through this event mecanism.</p>
 <p>If you go further and look at CDI plugin API you'll realize it is simply the same kind of events. CDI events is really the basis of CDI.</p>
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	<div class="row">

	<div class="col-md-12">
	<h1>CDI events: loose coupling and extensibility</h1>
	<p>CDI allows you to extend business code by the Notifier/Observer pattern.</p>
	<p>To do it you simply inject a field <code>Event</code> in the notifier class. This class is a template and the parameter type is the object type to fire. Then when you want to notify observers you simply call the method fire of the event object passing as a parameter the event itself<br/>(your own class!).</p>
	<p>On the other side you annotated a method parameter <code>@Observes</code> and the parameter type is the sent type by the notifier.</p>
	<p>Note: of course you can add qualifiers to be more precise on your events.</p>
	<h1>The example</h1>
	<p>The example is pretty simple: an ejb uses the <code>@Schedule</code> annotation to get a notification each second. The each second this EJB will send the current date through CDI events.</p>
	<p>This is our "business" code. It is a simple behavior (nothing).</p>
	<p>In our test (which is considered as an extension) we created an observer (<code>Observer</code> class) which simply store and log each received date.</p>
	<p>The test itself (<code>EventTest</code>) simply verifies the dates were received.</p>
	<h1>Conclusion</h1>
	<p>CDI let's implement very easily plugins through this event mecanism.</p>
	<p>If you go further and look at CDI plugin API you'll realize it is simply the same kind of events. CDI events is really the basis of CDI.</p>
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