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Okay so we've fixed our problem with
restricting changes to our character name,

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00:00:05,220 --> 00:00:07,120
but it's a little too restrictive.

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00:00:07,120 --> 00:00:09,950
It can't even be accessed from
outside the class itself.

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00:00:09,950 --> 00:00:13,840
We want to allow consumers of our objects
to still be able to see the value,

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00:00:13,840 --> 00:00:15,800
even if they can't change it.

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00:00:15,800 --> 00:00:18,640
So how do we let them get the value then,
you ask?

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00:00:18,640 --> 00:00:19,590
Great question.

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00:00:19,590 --> 00:00:23,065
Well the answer is we build
a method that exposes a value.

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00:00:23,065 --> 00:00:27,301
You've used methods before but for
instance on the console object use

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00:00:27,301 --> 00:00:31,190
the print F method or on strings
we use the two lower case method.

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00:00:31,190 --> 00:00:35,205
Now remember what I said that developers
modeling the real world objects focus on

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two main characteristics
which are state and behavior.

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00:00:38,490 --> 00:00:41,660
Well fields usually are used
to express that state and

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00:00:41,660 --> 00:00:44,350
its methods help us to
express that behavior.

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00:00:44,350 --> 00:00:47,030
So, therefore you can kind of think of
fields as characteristics about your

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00:00:47,030 --> 00:00:50,780
object and methods as the verbs or
actions that your object can perform.

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00:00:51,840 --> 00:00:55,760
So, just like how you've use methods on
objects before, like string contains or

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integer percent, it's time that
we learn how to write our own.

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00:00:59,480 --> 00:01:00,980
Okay, so let's do this.

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00:01:00,980 --> 00:01:04,640
Let's add a method to our
object that behaves like this.

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00:01:04,640 --> 00:01:08,780
When the method is used or
called it will respond with or

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00:01:08,780 --> 00:01:10,940
return to the calling code.

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00:01:10,940 --> 00:01:14,330
The value of the private
field character name.

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00:01:14,330 --> 00:01:18,955
Now defining a method is pretty similar
More to the way that we define a field.

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00:01:18,955 --> 00:01:21,205
They also have access modifiers.

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So let's come here.

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00:01:22,425 --> 00:01:23,405
So when I come in here and

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00:01:23,405 --> 00:01:25,405
say we definitely we want
this to be public right.

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00:01:25,405 --> 00:01:27,875
We want this to be accessible,
that's the point of what we're doing.

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00:01:27,875 --> 00:01:30,567
So we'll start with public and now,

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00:01:30,567 --> 00:01:35,237
we need to define what type of data
will be returned from this method,

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00:01:35,237 --> 00:01:39,287
meaning when I call this method, what
type of answer will I get back from it.

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00:01:39,287 --> 00:01:40,807
For instance, let's look at one.

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00:01:40,807 --> 00:01:43,437
So if we look at the method
string.contains,

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00:01:43,437 --> 00:01:45,557
remember you use that to find
out if something's in there.

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00:01:45,557 --> 00:01:48,157
So that is definitely a public method,
right.

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00:01:48,157 --> 00:01:52,690
We are using that, and
it returns a Boolean okay.

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00:01:52,690 --> 00:01:57,010
So we said that our method was going
to be returning a string, right?

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00:01:57,010 --> 00:01:58,080
It's the character name.

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00:01:58,080 --> 00:02:02,150
It's a string so so we say, public string.

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00:02:03,590 --> 00:02:08,085
And next is the method name so
we're going to get the character names so

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00:02:08,085 --> 00:02:10,720
getCharacterName.

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00:02:10,720 --> 00:02:13,870
Now, here's the part that makes it
different than the field definition.

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00:02:13,870 --> 00:02:15,380
Look, it looks pretty similar, right?

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00:02:15,380 --> 00:02:18,430
What we're going to do is we're
going to open parentheses

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00:02:18,430 --> 00:02:21,750
stating that this is indeed a method and
it's expected to be called.

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00:02:21,750 --> 00:02:24,390
So, here is where you
would define parameters,

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00:02:24,390 --> 00:02:25,810
that's if your method needs it.

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00:02:25,810 --> 00:02:30,500
So, if we come back to the string contains
method, so it's a public Boolean that

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00:02:30,500 --> 00:02:35,420
contains is the name of the method and
again it opens up its parentheses.

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00:02:35,420 --> 00:02:41,750
And it needs to know, a parameter we pass
in the string containing words right?

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00:02:41,750 --> 00:02:42,520
Remember we did that.

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00:02:42,520 --> 00:02:46,340
So back at our example of contains it
needs you to specify what you're looking

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00:02:46,340 --> 00:02:50,690
for the contains method
takes a string argument.

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00:02:50,690 --> 00:02:56,250
So it's a string of the matching
text that you're looking for, right?

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00:02:56,250 --> 00:02:58,525
It specifies that parameter list.

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00:02:58,525 --> 00:03:01,900
We'll go over these in a bit but currently
our method doesn't need any parameters.

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00:03:01,900 --> 00:03:07,490
So we'll just go ahead and close it and
then we'll start our methods body.

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00:03:07,490 --> 00:03:14,210
So it's opening up a new scope and I'll
write right away to put the closing brace.

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00:03:14,210 --> 00:03:17,420
So you see all of the editor lines up
the braces, it's really nice this way.

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00:03:17,420 --> 00:03:22,370
So now if I come here, I know this is the
class scope and here is this method scope.

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00:03:22,370 --> 00:03:26,020
It's a nice way to make sure that
everything's lining up in one class.

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00:03:26,020 --> 00:03:28,330
Okay, back to our method.

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00:03:28,330 --> 00:03:33,730
In this scope here in this code
block we can write whatever we want.

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00:03:33,730 --> 00:03:38,590
In here we can write whatever code the
method should perform when it's called.

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00:03:38,590 --> 00:03:39,890
Finally, what should happen is,

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00:03:39,890 --> 00:03:44,660
it should return a value of its
expected type, which is string.

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00:03:44,660 --> 00:03:49,710
So it's going to use the keyword return.

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00:03:49,710 --> 00:03:53,061
And we're going to return
the characterName, right?

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00:03:53,061 --> 00:03:57,700
And the character name is
a string characterName.

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00:03:57,700 --> 00:03:59,060
So here's the characterName.

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00:03:59,060 --> 00:04:03,120
It's going to return this and because it's
in the scope right it's in this class

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00:04:03,120 --> 00:04:07,030
scope it has access to this
even though it's private.

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00:04:07,030 --> 00:04:12,990
The prefix of get here is part
of a very common pattern.

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00:04:12,990 --> 00:04:17,190
It's called a getter, this pattern
of getter for a specific field

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00:04:17,190 --> 00:04:22,365
is to name them with get followed by
the name of the field just like we did.

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00:04:22,365 --> 00:04:27,370
GetCharacterName so
you can see it's get and

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00:04:27,370 --> 00:04:31,530
then character a name and it's getting
this private field character name here.

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00:04:31,530 --> 00:04:34,710
So methods that are used to change
the state of these objects or

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00:04:34,710 --> 00:04:37,760
set a field value
are prefixed with set and

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00:04:37,760 --> 00:04:41,910
those are called of course setters so
together these getters and

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00:04:41,910 --> 00:04:46,100
setters are often referred to as
properties in other languages.

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00:04:46,100 --> 00:04:49,430
They'll become very common practice for
you in your job adventures.

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00:04:49,430 --> 00:04:52,220
Okay, so
now let's flip back to the example.

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00:04:52,220 --> 00:04:56,779
I'm gonna go ahead and before we do that,
I'm gonna get rid of this comment here.

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00:04:56,779 --> 00:05:01,420
I wanna save this file, and let's
flip back to example and take a look.

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00:05:01,420 --> 00:05:04,770
So we know that the code in here doesn't
compile remember it wasn't compiling,

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00:05:04,770 --> 00:05:05,310
so let's go ahead.

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00:05:05,310 --> 00:05:08,180
Let's get rid of this Darth Vader cuz
we're not gonna change that anymore,

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00:05:08,180 --> 00:05:08,680
it's private.

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00:05:10,650 --> 00:05:16,040
But now, instead of accessing the private
field character name, let's try to access

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00:05:16,040 --> 00:05:20,320
the public method, getCharacterName,
and we're going to call that method.

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00:05:20,320 --> 00:05:24,610
So there's some parens I'll put
this down in a new line in here.

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00:05:24,610 --> 00:05:27,620
This is highlighting, this is this, okay.

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00:05:27,620 --> 00:05:30,756
So we're going to call the method,
getCharacterName and

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00:05:30,756 --> 00:05:32,742
that's going to return the method.

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00:05:32,742 --> 00:05:34,960
So let's go ahead and
let's compile it and run it.

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00:05:37,000 --> 00:05:39,510
I forgot to save it important note
there see the little red dot.

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00:05:41,550 --> 00:05:42,560
So compile it and run it.

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00:05:44,280 --> 00:05:46,060
Boom we got it, it's back.

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00:05:46,060 --> 00:05:51,670
So again the method was called and
our code inside of that method.

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00:05:51,670 --> 00:05:57,305
This method body here was run and we
returned the private field characterName.

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00:05:58,430 --> 00:06:02,140
And that's definitely more like how
things work in real life, right?

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00:06:02,140 --> 00:06:05,610
People can't just go changing
the character on these pez dispensers and

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00:06:05,610 --> 00:06:09,680
now we are clearly communicating that
reality because we haven't added a setter

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00:06:09,680 --> 00:06:13,200
we've only add it together so
nobody can set that.

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00:06:13,200 --> 00:06:18,180
Now, one thing you're probably wondering
is well, we can't change it at all,

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00:06:18,180 --> 00:06:21,470
right, it's always going to be Yoda.

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00:06:21,470 --> 00:06:22,260
That's a good point.

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00:06:22,260 --> 00:06:25,780
Let's tackle that next awesome
job modeling the character.

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00:06:25,780 --> 00:06:28,530
Now it can't be changed only retrieved.

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00:06:28,530 --> 00:06:31,400
This is a very common pattern
used to express how you'd

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00:06:31,400 --> 00:06:33,530
like people to interact with your object.

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00:06:33,530 --> 00:06:35,910
We'll run through it a couple more
times in the course just to make sure

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00:06:35,910 --> 00:06:37,320
that it's sinking it.

116
00:06:37,320 --> 00:06:40,290
So we left another problem in there,
didn't we?

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00:06:40,290 --> 00:06:43,850
Every single Pez dispenser that we
create is gonna be a Yoda character.

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00:06:43,850 --> 00:06:46,980
That's certainly gonna bum out some kids
who want a Teenage Mutant Ninja Turtle or

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00:06:46,980 --> 00:06:50,630
an Elsa version, and for
sure sales are gonna plummet.

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00:06:50,630 --> 00:06:53,770
Let's do a quick exercise to make sure
that we got this private keyword and

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00:06:53,770 --> 00:06:55,060
getter method thing figured out, and

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00:06:55,060 --> 00:06:57,710
then we'll fix this Yoda only
situation that we got ourselves into.