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So befalling the MVC architecture for our project and this is for model view controller.

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Unequals was conceived in 1970s for developing graphical user interface applications and this is extremely

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popular for developing web applications.

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So you might wonder why we are implementing this architecture which is related to web applications in

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a Java course.

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Main reason for this is typically most people once they learn Java they tend to get into application

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development very is the pattern that's most commonly used.

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So if you choose to get into web development then it would be relatively easy and a good progression

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for you.

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After doing this course.

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The reason I say it's a good progression is because in this project you will implement busy in the right

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way.

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More on my thing about MVC is it lots of different layers as we will soon see.

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And there's a nice division of responsibilities between these different layers.

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There is a layer sort of loosley couple of objects in these leaders communicate with each other.

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So it's always an object oriented language aggrievement nice to implement something where we have a

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lot of objects in mind.

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So you will see a lot of object creation and object to object communication.

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And this project Somalo to look at what the different layers in NBC are.

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There are three layers.

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The Model View and controller model holds the business logic and it usually has two suppliers.

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One is a service layer which has a real business logic while the other is the dollar which communicates

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with database and so typically in a school where is not a dollar short for data access objects in a

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Java project model would encourage polocrosse the classes and service layer are usually referred to

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as managers or alternatively or services underclasses and dourly or are usually referred to as Goffs

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.

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We use a presentation layer that is a friend and in Java world JS piece would represent the view human

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or that just be shot for Jalla so pages not coming to controller.

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It basically separates modern from the view and you will have soldiers here which are also Djala programs

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.

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So controller and motor would encourage job programs which reside in the backend.

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That is a sour note with regards to data flow.

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A user would perform some action in the browser like requesting for some data or submitting some form

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data.

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Either way action would involve some matter.

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And one of the controllers in the Bakken if action involves submitting data then the matter that the

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controller would also be bastardy dumb controller would then call the service layer which includes business

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logic.

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As mentioned earlier the business logic would involve invoking that dollar which either retrieves data

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from the database or inserts data into the database depending on the type of action performed in the

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front and if data is being retrieved from the database then it would be passed back with a view in the

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reverse order that is darf the service layer.

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So it's layer to controller and controller to the presentation layer.

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Now the advantage of NBC is that it separates business logic from the presentation layer.

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This enables business logic to be reused across different applications.

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For example you can use the same business logic for because coming from the web or mobile applications

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or even web services not coming to our project although it's not a full blown web application we would

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like to keep our implementation Oskaloosa be a real web application as possible.

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We will implement both model and controller.

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There is movement in Bremen controllers.

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Managers are not as they would be in a typical web application form you even use a Java class.

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So actions speak and in a browser are semiliterate using methods in the Java class next for database

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.

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We will again use a single Java class named datastore and one of the future versions of the project

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.

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We may use a real database like my Escorial But for now it will be a Jalla class.

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Finally if you don't implement something call entities which are nothing but classes like user bookmark

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book movie and wabbling which we are already familiar with.

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So entities are simple Djala classes undercards point to database tables.

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That is indeed obvious.

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You'd also have people like user bookmark book and so on and each instance of an entity corresponds

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to a role in a database table.

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So if we use frameworks like Hibernate.

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Entities can be directly silverbeet is that is hibernate will automatically transform an entity object

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into an obscure query visual to insert the data in the appropriate table.

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Just don't worry if you have never used a database or you have never read an obscure before.

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It's definitely not that relevant here.

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Also there are a couple of minor things I want to mention before we move on.

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Since this project is a simulation of MVC framework there are a few minor things that are implemented

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slightly differently from how we discussed earlier.

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For example some of the methods in user class like saving bookmarks would be mumbling to a manager class

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and that's purely because we are implementing the project as NBC and it makes more sense to implement

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this.

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The second thing is the code for the project will not be available for download.

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So you will have to implement everything as the project is being demonstrated.

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Finally with regards to implementation time I think the VTR time would come around two and a half hours

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.

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But I would assume it might take around 8 hours reimplemented.

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But in reality it might take a few more days to implement even this fast version.

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That's because we are not considering the time that I had to invest in designing the architecture based

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on the requirements.

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So in your professional life you will spend significant time during design office in general from my

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personal experience.

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I would recommend spending some extra time during design phase itself and get your design right.

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That way you will minimize the chances for refactoring later when you're implementing the project.

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All in all I think it's a good project.

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It's not that complex and everything will be demonstrative in a very clearly.

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All right then let's get started and make our hands dirty.