Issue #469: Implementation of Event-based Asynchronous pattern

event-asynchronous/README.md

@@ -0,0 +1,28 @@
+---
+layout: pattern
+title: Event-based Asynchronous
+folder: event-asynchronous
+permalink: /patterns/event-asynchronous/
+categories: Other
+tags:
+ - Java
+---
+
+## Intent
+The Event-based Asynchronous Pattern makes available the advantages of multithreaded applications while hiding many
+of the complex issues inherent in multithreaded design. Using a class that supports this pattern can allow you to:-
+(1) Perform time-consuming tasks, such as downloads and database operations, "in the background," without interrupting your application. 
+(2) Execute multiple operations simultaneously, receiving notifications when each completes. 
+(3) Wait for resources to become available without stopping ("hanging") your application. 
+(4) Communicate with pending asynchronous operations using the familiar events-and-delegates model.
+
+![alt text](./etc/event-asynchronous.png "Event-based Asynchronous")
+
+## Applicability
+Use the Event-based Asynchronous pattern(s) when
+
+* Time-consuming tasks are needed to run in the background without disrupting the current application.
+
+## Credits
+
+* [Event-based Asynchronous Pattern Overview](https://msdn.microsoft.com/en-us/library/wewwczdw%28v=vs.110%29.aspx?f=255&MSPPError=-2147217396)