From the course: Java Design Patterns: Behavioral Part 2
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Challenge: The Observer pattern - Java Tutorial
From the course: Java Design Patterns: Behavioral Part 2
Challenge: The Observer pattern
(upbeat music) - [Instructor] Let's have a look at our first exercise. In this one, you're going to be refactoring an app that posts traffic updates for various cities. So let's have a look at the code so far. First of all, there is a class called City, which has a string field called trafficUpdate. And a method called updateTraffic to update that field. This class is going to be the observable. Then there's a class called TrafficUpdates, which is going to be the observer. This has an array list of strings called updates and a method called getUpdates, which prints out every update in the list. Finally, there is a Main class with a main method. In here, I'm creating two City objects, sunnyville and springfield. And I'm creating a trafficUpdates class and then I'm updating the traffic for both cities. So in Sunnyville, there is congestion in the town center and in Springfield, there's an accident on the highway.…
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