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Now we're ready to build the dealership application.
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In this section, you learn to control how your code runs using false statements and switch statements.
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The AFL statement uses conditions that return either true or false.
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And the Switch statement compares a value to a list of cases.
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Now, the apps we built so far in this section are static in the sense that they use predefined values.
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If you want to take your application from static to dynamic values, need to come from the user, like
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what you're seeing here.
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And so the goal of the next three lessons is to build an interactive dealership application.
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This application is going to test everything that you learned so far, so let's get started.
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First thing I'll need you to do is create a new class by yourself inside the Section three folder.
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Create a new file named Dealership de Java and make sure the class has a main method.
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Let's do some review.
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What is the scanner?
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Scanner waits for the user to enter a value in the terminal for this app, we need to ask the user some
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questions.
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Then Skinner needs to wait for the user to enter some text.
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We do that with scanned next line, and then the user must go to the terminal type text and press enter.
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Once the user presses enter scan, the next line picks up the text and stores it in the variable.
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We need to import Skinner in order to use it.
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We'll start by making a new instance of scanner scanner scan.
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Is equal to new scanner that can receive input from the system system.
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And now this line of code should come with an error because remember, we have to import scanner before
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we can use it.
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And what's really convenient is that Visual Studio code as a cool auto import feature, let's assume
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you want to use scanner, but you don't know where to import it from and you're too lazy to look it
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up.
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Well, just write scanner.
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Wait for the scanner option to show up.
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Click on it and VSCO knows to import it for you.
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That's pretty cool.
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If you're too lazy to look up or to import something from, then this feature has you covered.
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All right, it's time to build the app at the Java dealership, clients can buy a car or Selwyn first,
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your app should give the client a warm welcome.
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So we're going to print.
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Welcome to the Java dealership.
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Then it should give the user the option to buy a car or sell one.
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So first, I'm going to print.
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Select option to buy a car.
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Followed by another print where we say.
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Select Option B to sell a car.
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Let's run our code.
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And we're off to a very good start.
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The next thing we need to do is use scanner to get values from the user.
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Remember that scan the next line waits for the user to enter a string.
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Here, your application presents the user with a bunch of options, and we need the right string option
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is equal to scan.
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Next line, which is going to wait for the user to enter a string value.
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Let's rerun our code.
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And everything works as we expect.
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Stand up next line waits for the user to enter their next string.
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And the user went to the terminal and typed an option.
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Now, before we use this value and move forward, you might have this burning question inside you that
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I want to address.
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Why didn't we use car?
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Well, next line reads the input as a string value.
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If you hover over the next line method, it says that it returns a string.
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So no matter what the user writes, it will be interpreted as a string.
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And you cannot store a string inside of a car variable.
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There are ways to work around the situation, but it's honestly not worth the headache.
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The input comes in as a string, so let's just treat it as such.
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Now we can use which to compare the user's option against the list of options.
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There are only two options A and B, so we're going to make a switch statement.
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And it's going to compare the option.
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Against Case A.
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In case B.
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And as always, we're going to add the usual default case.
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Based on what the user chooses, we're going to print.
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You chose option and will close the string and connect the option that they chose.
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And if the user chooses something else, we're going to print.
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Invalid option.
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If you happen to be yelling at your screen and you forgot the brake keywords, then you're learning
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fast.
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In any case, when there's a case match switch runs every case that follows.
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So don't forget that the break you were at at the end of each case.
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Rerunning our code.
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That looks a lot better.
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Switch compares your value against each case.
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It matches Case A Java runs case A and then it sees the break key keyword, which ends up breaking the
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sweat statements.
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Always remember to add the break you were at the end of each case.
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Once you're done with scanner, you need to close it if you want to avoid a memory leak.
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So we're going to close the scanner with scan dark cloak.
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It's good practice.
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And now we're all done.
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In this lesson, you started building the dealership application in the next one, we're going to add
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some logic for Case A buying a car.
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