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Determining If the Game is Won
8:09We will use loops and chaining to solve the final story: As a guesser, I should be able to know when the game is solved or failed, so that I can acknowledge completion with celebration or tears.
Here it comes, the last story to
complete our minimum viable product.
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If you thought it felt good to move
the stories to the Done column,
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wait until you see what it feels
like to move the last one.
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So here it is.
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As a guesser, I should be able to
know when the game is won or lost so
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that I can acknowledge completion
with celebration or tears.
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All right, we can definitely do this.
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So we should provide a method
that returns whether or
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not the game [SOUND] was
completed successfully.
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So how do we do that?
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Well, one way to do it is just to check
and see if there's any blanks left.
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We should just start with this approach.
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[SOUND] If there is a blank,
the game has not been won.
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And then we should have the prompter
display the final outcome,
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spreading the good or
bad news to our users.
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Here we go.
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All right, let's move our final ticket
over to the In Progress column.
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We need to let people know if they won or
not.
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So, let's go to Game really quick,
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let's stop our program from running,
and let's get in here.
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Let's say, we need to let
the game know if it's won or not.
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So let's just go ahead and
let's put it here.
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Let's say, public and
its true and false, right?
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So boolean and isWon,
and remember is, is the,
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like the getter,
it's a computed getter, right?
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So, we're gonna say isWon,
where normally if it was not boolean,
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it would have been get for
the stringer and integer or something.
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But it's is because that's
the format of the reason.
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And we're going to calculate our value,
so let's just use that
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existing method like we talked about,
so as I getCurrentProgress.
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Now, I could store this in a variable,
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but I know that this is
going to return a string.
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And so that string has a method on it that
allows us to see if a character exists.
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What was that called again, indexOf.
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So, what I can do is I can do a .indexOf,
right?
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So it's method chaining.
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And we wanna see if there is in fact,
any of those dashes in there.
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It's probably a good
place to make a constant,
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if we wanted to make
this a little bit better.
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And then we want to check and
see if it was, in fact, not found.
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So we're gonna say, is it not found?
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If that's not found, they won.
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That's the logic theory.
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Cool.
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So this returns a string.
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And then that string is
checked to see if it's dashes.
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And then we see,
if there are any dashes in there.
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Then they have, in fact, not won,
cuz their stuff left to guess.
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Okay, so let's go use it.
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In our main program here, in Hangman.java.
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We want the game to stop
looping once it's been won.
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Now this logic might be
a little challenging here, but
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let's think it through.
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So currently the loop goes as long
as there are remaining tries.
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So we wanna add another condition,
and it really is this.
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As long as the game hasn't been won.
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Okay, so while there are remaining tries,
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and we just wrote that game is won, but
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what we want is not won.
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It's so hard to not do a bar
impersonation here, not.
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Sorry, so that's what we want.
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Where both of these are true,
keep going, right?
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So we wanna keep going where
both of these are true.
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When this is checked, it will keep
going and each one of these will go.
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So when it's all done,
we wanna display the outcome, right?
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So, we would do something like this,
right?
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So it's a prompter.displayOutcome.
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Now, we haven't written that method yet,
but I bet you could.
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Why don't you go ahead and pause me?
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What we're gonna do before you pause,
let's get the instructions.
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What we're gonna do here is we're
gonna try to show if they've won,
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we're gonna say, congratulations.
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And if they failed, we're gonna say,
sorry, here's what the answer was.
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So why don't you go write that method?
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And notice, it doesn't return anything.
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Okay, go ahead, pause me and
come back when you're ready.
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Cool, this is how I did it.
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So, under displayProgress here,
I added a new method.
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And of course, it doesn't return anything.
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So that's a void.
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Display outcome.
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All right, so if the game was won,
we wanna say, congratulations.
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So let's say, if game is won.
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I'm gonna close my if and
I'm gonna say, else and
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then that's where we're gonna put this,
add here.
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So here we go.
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So, we want to say system.out.printf.
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Congratulations, you won with,
let's go ahead and
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say how many tries they had remaining.
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With %d tries remaining.
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Again, we'll extra feature there.
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Wasn't asked for.
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Maybe we shouldn't do that.
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We'll see what they think of the demo.
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All right, so
you won with that many tries remaining,
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and we're going to say,
game.getRemainingTries.
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Otherwise, we're
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going to .out.printf,
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Bummer, the word was %s.
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And I'm gonna make a sad face there,
we'll say, %n.
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Okay, and then we need to get
access to the answer, don't we?
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Prompter doesn't have
access to the answer.
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So I'm gonna write a getAnswer method over
here, sounds a little tricky wasn't it?
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So over here in Game, I'm gonna
make a getter for getAnswer, right?
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So our answer is still private but
we can add a getter,
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want to add a getter up here at the top.
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So we'll say our public,
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we want this to be public.
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And it's a string and we wanna say,
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getAnswer, and it doesn't expect anything,
and we are going to return the answer.
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Cool, let's see how I did.
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I'm sure you did great, clear && javac
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Hangman.java && java Hangman.
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Let's test it, T-R-E-H-O-U-S.
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We did it with seven tries remaining,
awesome.
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Okay, let's try to fail really quick.
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A-B-C-D-E-F-G-I.
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Bummer, the word history was treehouse,
sad face.
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My gosh, we did it, the sprint is over.
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[APPLAUSE]
>> Wohoo, we just did it.
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We got a working Hangman MVP.
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And what a great job of separating
the prompting from the game logic.
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Now, we could do a web-based version of
this, or use it in an Android app, or
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play it on a WiFi enabled refrigerator,
you get the point.
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The other great thing about this
game class that we created is that
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the implementation details are hidden.
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We absolutely could make this game more
efficient as long as we kept up our end
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of the deal, and we kept the interface,
or the exposed methods and functionality.
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If we kept those the same, every
single one of the users of this class,
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the console, the website, the Android app,
the refrigerator, they'd all benefit.
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Also, because you did a great job of
naming your methods, almost any English
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speaker could pick up that class and know
exactly what it's expected to do without
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ever seeing the methods code, just like
that radio example we talked about.
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Great job harnessing the power of objects.
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One more thing I told you that I'd show
you was how to pass an arguments to
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the command line.
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I mean after all,
if you're gonna play this game,
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you probably want to eventually use
a different word than treehouse, right?
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First though, an exercise.
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