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So we left our program in
a bit of a broken state.

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What we wanna do is prompt our
user to ask how old they are.

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We know how to do that,
as we've done that already, right?

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But there's a slight problem.

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The method that we've been using,
readLine, well, that returns a String.

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But as we know now,

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when dealing with numbers we want
to use the Integer data type.

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So somehow we need to get
an int from a String.

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I know, how about we ask the Internet and
see what we get back?

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00:00:27,450 --> 00:00:31,470
Okay, so I'm gonna go ahead and do a
search for exactly what we're looking for,

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which is Java get an int from a string.

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And we'll take a look at what we got here.

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This very first one is from
a website called Stack Overflow,

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which is a great resource for a developer.

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Lets see if it's, indeed,
what we're looking for.

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It says here, how does one convert
a String to an Int in Java?

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That is exactly what we need.

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See, I have a string which
contains only numbers, and

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I wanna return a number which represents
it, which is what we want to do,

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cuz we want to use the Int
to be compared in there.

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So let's go scroll down to
what the answers are so

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that you see there are seventeen answers,
and this one has a thousand votes.

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You can upvote if it worked for you, and

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then there is a check mark saying
that this worked for that person.

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So let's see if it works for us.

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So it looks like you use
this Integer.parseInt.

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Look there's a link to the Java Doc.

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Let's go ahead and click that,
this is the actual Java documentation.

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So let's see.

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So it says that parseInt will return
an int, and it takes a String,

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which is what we have.

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This looks like exactly what we want.

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Let's go ahead and
let's jump back over to our code.

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And let's pull out the age from the line.

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So we're gonna pull out a String first.

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So we'll say console.readLine and
we know that that gives us a String.

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We'll say how old are you?

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Great.
So now we have ageAsString is a String

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variable, so let's go ahead and let's
change this int age that we have here,

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and we'll say Integer with
the capital I .parseInt,

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and we'll paste on that ageAsString.

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Great, and now I'm gonna save it.

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And let's see if that worked.

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File and run.

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And it says how old are you?

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So let's try and
make sure that it fails and say 10.

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Great, that worked.

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Let's go again one more time And remember
we said, so if they're older than 13.

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So let's go and say they we're 15.

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Excellent, it started working.

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So, if you're in a program
that's executing like this,

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you can always press Control-C and
it will stop.

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Great job leaning on the Internet.

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We now know how to parse
Integers out of Strings.

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This is also referred to as
converting a String to an Integer.

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Switching between types is
also often called casting,

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which we'll cover in a future course.

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You also did a great job ignoring the fact
that we introduced a new class Integer

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with a capital I.

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In the past, we were using the all
lowercase primitive data type int.

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We used the new Integer
class's static method parseInt

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to generate a primitive int.

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This capital I Integer here is what is
known as a wrapper type, or a boxed type.

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And what it does for

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us is it provides some methods that we can
use to manipulate and produce Integers.

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Remember, primitive data
types do not expose methods.

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So there are these wrapper classes for
every one of the primitive data types.

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Again, the other data type that we had
worked with in the past was String.

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We're going to need to explore the methods
available to us because I'd also like to

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do something about those names I was
being called during our beta test.

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But first,
let's do an exercise on parsing Integers.