1
00:00:00,970 --> 00:00:05,320
All right, so now we have the ability to
apply a guess and keep track of hits and

2
00:00:05,320 --> 00:00:09,710
misses, the time has come to actually
take some input from the user.

3
00:00:09,710 --> 00:00:12,192
Now this is probably going to look
a little strange in our current state,

4
00:00:12,192 --> 00:00:16,155
until we get some of the more detailed
stories like the ones that shows

5
00:00:16,155 --> 00:00:17,765
the current progress for example.

6
00:00:17,765 --> 00:00:22,105
This is gonna be fairly useless except for
a cool trick at the command line.

7
00:00:22,105 --> 00:00:25,195
What I mean is this we haven't even
shown users of our hang man app

8
00:00:25,195 --> 00:00:29,137
what they are attempting to guess but
here we are asking them for their guests.

9
00:00:29,137 --> 00:00:33,267
Now this half baked app is definitely
part of the development process.

10
00:00:33,267 --> 00:00:34,527
Once we get some things working.

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00:00:34,527 --> 00:00:37,807
We can iterate on the concepts until
we get to our working product.

12
00:00:37,807 --> 00:00:42,433
But development isn't always Is linear and
we have to start somewhere right

13
00:00:42,433 --> 00:00:45,613
now as long as we complete all
the stories on our test board.

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00:00:45,613 --> 00:00:48,383
We know we'll get there and we do that,
because we've looked at them.

15
00:00:48,383 --> 00:00:51,523
Okay, so let's get our prompter
able to accept guesses.

16
00:00:53,053 --> 00:00:57,403
Okay, so we currently don't have anything
at all in our prompter class, and

17
00:00:57,403 --> 00:01:00,853
I wanna get back to a statement
that I made earlier.

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00:01:01,870 --> 00:01:05,310
About how someone else
will be using your code.

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00:01:05,310 --> 00:01:08,370
So the problem here that we're
gonna be writing is going to

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00:01:08,370 --> 00:01:10,280
use the game code that we just wrote.

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00:01:10,280 --> 00:01:14,410
Now, it's possible but we're on a team and
we've made a team responsible for

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00:01:14,410 --> 00:01:15,360
prompting.

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00:01:15,360 --> 00:01:17,510
The front in portion of our app.

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00:01:17,510 --> 00:01:20,720
The prompter is going to need
to know about our game object.

25
00:01:20,720 --> 00:01:22,180
So let's do that.

26
00:01:22,180 --> 00:01:27,020
Lets store a private variable
that is an instance of our game.

27
00:01:27,020 --> 00:01:31,600
So we'll say game game, and
again we wanted to make that private.

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00:01:31,600 --> 00:01:36,250
We always want to start private, What

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00:01:36,250 --> 00:01:40,150
good is one of these prompters
without a reference to our game.

30
00:01:40,150 --> 00:01:46,400
So let's require one for instantiation
by defining it in our constructor.

31
00:01:46,400 --> 00:01:48,240
So again, let's make a constructor.

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00:01:48,240 --> 00:01:52,240
So I'll say, public and
it's the same name as the class prompter.

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00:01:54,420 --> 00:01:56,810
And we're going to require a game.

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00:01:56,810 --> 00:02:00,790
So the game is the type game and
we'll call it game.

35
00:02:00,790 --> 00:02:03,700
And of course we have our little
naming collision problem again.

36
00:02:03,700 --> 00:02:07,330
So we wanna talk about
the private variable game.

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00:02:07,330 --> 00:02:10,680
And set that equal to
the argument that came in.

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00:02:11,950 --> 00:02:14,960
Wanted to show you another little
trick really quick here in jshel.

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00:02:16,080 --> 00:02:20,790
So, if we have a string, so
we have string example equals hello.

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00:02:22,290 --> 00:02:25,310
If I wanted to get a specific
character out of that,

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00:02:25,310 --> 00:02:29,760
there is a Method on
strings called charAt.

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00:02:29,760 --> 00:02:30,890
So, I can say charAt.

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00:02:30,890 --> 00:02:33,870
So, let's say that I wanted
to get the first character.

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00:02:33,870 --> 00:02:36,100
So that's one, right?

45
00:02:36,100 --> 00:02:38,970
No, zero is the first, I [LAUGH] forgot.

46
00:02:38,970 --> 00:02:39,920
Baby years right?

47
00:02:39,920 --> 00:02:41,540
So zero will get me a.

48
00:02:41,540 --> 00:02:45,280
So the very first character that, awesome.

49
00:02:45,280 --> 00:02:50,080
Okay, now, in our prompter object,

50
00:02:50,080 --> 00:02:53,310
let's add a method that will prompt for

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00:02:53,310 --> 00:02:57,420
a guess, and it will return whether or
not the guess was correct.

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00:02:57,420 --> 00:03:00,200
That sounds pretty boolean to me, right?

53
00:03:00,200 --> 00:03:01,490
So, we want this to be public.

54
00:03:01,490 --> 00:03:06,330
We wanna allow this to be called, so we'll
say boolean, and that's gonna, again,

55
00:03:06,330 --> 00:03:10,888
be whether or not the guess was
correct Say promptForGuess.

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00:03:10,888 --> 00:03:16,808
[SOUND] Okay, now you've probably used
the console object before which happens

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00:03:16,808 --> 00:03:21,943
to be one of many ways that's used
to get input and output from a user.

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00:03:21,943 --> 00:03:27,270
But for the sake of learning new tricks,
let's use a handy object called scanner.

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00:03:27,270 --> 00:03:30,010
Now a scanner lives in
the different package.

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00:03:30,010 --> 00:03:32,860
Than where all the other things
we've been importing are.

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00:03:32,860 --> 00:03:34,890
It lives in the Java util package,

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00:03:34,890 --> 00:03:37,550
and what that means is
that we need to import it.

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00:03:37,550 --> 00:03:38,210
So let's do that.

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00:03:38,210 --> 00:03:44,520
Let's go up here, and
we'll say import java.util.scanner.

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00:03:44,520 --> 00:03:50,270
And what this does is it allows us to
have access to this class name, right?

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00:03:50,270 --> 00:03:54,470
So now,
we can create a new one of these types.

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00:03:54,470 --> 00:03:56,930
So scanner, when we create it.

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00:03:56,930 --> 00:03:58,100
So let's make a new one.

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00:03:58,100 --> 00:03:59,930
So we'll say Scanner, which is the type.

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00:03:59,930 --> 00:04:02,930
And we'll name it scanner,
our instance variable.

71
00:04:02,930 --> 00:04:04,360
And we'll make a brand new one of those.

72
00:04:04,360 --> 00:04:06,960
So we'll say new Scanner.

73
00:04:08,110 --> 00:04:12,231
So scanner expects us to define
where the input is coming from so

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00:04:12,231 --> 00:04:16,449
much like there's a system.out,
there is also a system.in.

75
00:04:19,988 --> 00:04:23,677
Okay, so now we need to prompt them,
we need to write out to the screen so

76
00:04:23,677 --> 00:04:25,370
we know how to do that already.

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00:04:25,370 --> 00:04:30,870
So we'll say system .out.print and
I want to keep things on the same line and

78
00:04:30,870 --> 00:04:32,880
I don't really need to
format anything here.

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00:04:32,880 --> 00:04:35,950
So let's just go ahead and we'll just
use the print command off of out.

80
00:04:35,950 --> 00:04:37,800
It's just another one of these commands.

81
00:04:37,800 --> 00:04:39,000
So as they enter a letter.

82
00:04:39,000 --> 00:04:43,910
And we'll do a couple spaces there so
that they have a space to enter it in,

83
00:04:45,350 --> 00:04:50,290
Scanner has a bunch of helper
methods that help Parse input.

84
00:04:50,290 --> 00:04:52,960
Parse meaning read and
figure out what it means there.

85
00:04:52,960 --> 00:04:56,350
So, much like how console
had the read line method.

86
00:04:56,350 --> 00:04:59,400
Scanner uses one called next line

87
00:04:59,400 --> 00:05:03,490
which allows us to read a line that
again happens when they press enter.

88
00:05:03,490 --> 00:05:04,150
So, let's do that.

89
00:05:04,150 --> 00:05:05,350
So we'll store it.

90
00:05:05,350 --> 00:05:06,860
We'll do string.

91
00:05:06,860 --> 00:05:09,820
Guess input and

92
00:05:09,820 --> 00:05:14,910
we'll do equals scanner.nextline and
note case there.

93
00:05:16,040 --> 00:05:20,240
Since our applied guess
method only takes a char

94
00:05:20,240 --> 00:05:24,110
we need to go get one of those using
that method that we saw, right?

95
00:05:24,110 --> 00:05:25,830
That char at.

96
00:05:25,830 --> 00:05:29,180
So let's pull from this guess
him put right we have a string.

97
00:05:29,180 --> 00:05:31,236
So let's get the first
character off of it.

98
00:05:31,236 --> 00:05:39,610
I guessInput.charAt... that first character
again is zero not one right, okay.

99
00:05:39,610 --> 00:05:42,490
So now, we have the guess.

100
00:05:42,490 --> 00:05:46,280
We need to see if that guess matches or
not but

101
00:05:46,280 --> 00:05:48,220
that's not the prompter's job right.

102
00:05:48,220 --> 00:05:49,580
That's the game's job.

103
00:05:49,580 --> 00:05:53,080
Now it's a good thing that we
passed in our game object, right.

104
00:05:53,080 --> 00:05:53,720
It's a good thing.

105
00:05:56,010 --> 00:06:00,890
Why don't we just return what
comes out of applied guess, right?

106
00:06:00,890 --> 00:06:03,160
So apply guess is going to come and
see if it exists and

107
00:06:03,160 --> 00:06:04,710
it's going to return a true or a false.

108
00:06:04,710 --> 00:06:11,370
So here we can do the same thing we
could just return game.applyGuess.

109
00:06:11,370 --> 00:06:15,210
And play that Guess where that finally

110
00:06:15,210 --> 00:06:20,360
let's add some code to hang man dot
java over here and let's use it.

111
00:06:20,360 --> 00:06:21,790
So, let's make a new prompter.

112
00:06:21,790 --> 00:06:22,530
So we know how to do that.

113
00:06:22,530 --> 00:06:24,350
It's a type prompter.

114
00:06:24,350 --> 00:06:26,810
It's a named prompter it's a new prompter.

115
00:06:26,810 --> 00:06:30,990
And remember the way that we're getting
the game in there is we're passing it

116
00:06:30,990 --> 00:06:33,820
through the constructor through prompter
constructor because what good is

117
00:06:33,820 --> 00:06:35,020
a prompter without the game.

118
00:06:35,020 --> 00:06:36,565
There we go game.

119
00:06:36,565 --> 00:06:41,300
Okay, so let's just write some simple
code just walk through what we just did.

120
00:06:41,300 --> 00:06:46,570
So we'll say boolean is hit

121
00:06:46,570 --> 00:06:52,340
prompter dot prompt for guess, and
again that's how we run our code.

122
00:06:52,340 --> 00:06:53,162
It's going to come in here.

123
00:06:53,162 --> 00:06:54,980
It's gonna create a new scanner
is going to print this line and

124
00:06:54,980 --> 00:06:56,050
then it's going to wait here.

125
00:06:56,050 --> 00:06:59,100
It's going to wait until we finish and
then it will go and go on through.

126
00:06:59,100 --> 00:07:01,300
So it's let's see.

127
00:07:01,300 --> 00:07:05,390
So once we get back that result from
whatever that we type then we'll say

128
00:07:05,390 --> 00:07:10,010
if is hits and
I'm gonna close that if right away.

129
00:07:11,290 --> 00:07:15,980
And then we'll say system.out.println.

130
00:07:15,980 --> 00:07:17,310
We got a hit.

131
00:07:18,800 --> 00:07:22,100
And obviously this is not something we
would ever say to the user because hit,

132
00:07:22,100 --> 00:07:25,070
what does it mean to them but
this is just for us to look at, all right.

133
00:07:25,070 --> 00:07:28,130
So this is something that you
might not have seen before.

134
00:07:28,130 --> 00:07:31,330
Now we want to say what happens if
they don't remember we need to do that

135
00:07:31,330 --> 00:07:33,480
branching that we saw else.

136
00:07:33,480 --> 00:07:36,985
We're gonna say

137
00:07:36,985 --> 00:07:45,140
system.out.printline, okay.

138
00:07:45,140 --> 00:07:48,270
So, look at this, I want to show this
is a common problem that happened.

139
00:07:48,270 --> 00:07:53,450
So, I forgot to put my
closing brace there,

140
00:07:53,450 --> 00:07:55,110
which I letting you in on the secret
o what I'm trying to do here.

141
00:07:55,110 --> 00:08:00,060
So look, this one close but this else
I didn't close it but it's grabbing.

142
00:08:00,060 --> 00:08:03,360
The methods it's actually the methods,
but see it's not highlighting the method.

143
00:08:03,360 --> 00:08:06,700
It should be and if I come here to
the class one, the class calls or

144
00:08:06,700 --> 00:08:09,220
it's highlighting there so
it's unbalanced.

145
00:08:09,220 --> 00:08:11,530
So, we wanna balance that there we go.

146
00:08:11,530 --> 00:08:13,320
So, now we look at this.

147
00:08:13,320 --> 00:08:14,470
All right now,

148
00:08:14,470 --> 00:08:20,410
let's pop over to our hangman Java here in
a press controlled lead jump at jShell.

149
00:08:20,410 --> 00:08:21,694
And let's do clear.

150
00:08:21,694 --> 00:08:27,636
And javac hangman dot java and

151
00:08:27,636 --> 00:08:30,730
java Hangman.

152
00:08:31,730 --> 00:08:32,950
Here we go.
So we've compiled it.

153
00:08:32,950 --> 00:08:39,030
We're gonna run it and we should see
our prompt Cool so enter a letter.

154
00:08:39,030 --> 00:08:39,680
Let's go ahead and

155
00:08:39,680 --> 00:08:43,900
guess what that's there will say t cuz
right it passed in the game treehouse.

156
00:08:43,900 --> 00:08:46,040
Okay, cool we got a hit and
then let's do it again.

157
00:08:46,040 --> 00:08:52,050
And let's put in z here and
we missed awesome it's working.

158
00:08:52,050 --> 00:08:55,100
So let's go take a look at
our story over here and

159
00:08:55,100 --> 00:08:59,210
see as a guesser I should be able to
submit a guess so I can play a game.

160
00:08:59,210 --> 00:09:03,420
I think we just did that I'm going
to go ahead and call that done.

161
00:09:05,020 --> 00:09:07,010
We completed our first story.

162
00:09:07,010 --> 00:09:10,780
Nothing quite like that feeling of
moving something to the done column.

163
00:09:10,780 --> 00:09:12,110
Now it might not be much.

164
00:09:12,110 --> 00:09:15,610
But now we can start into the other
stories that were blocked by this one,

165
00:09:15,610 --> 00:09:17,070
progress.

166
00:09:17,070 --> 00:09:19,390
Let's pick up the next one right
after we do this quick exercise.