- Reviewing Our Feedback 6:11
- Conditional ints 3 objectives
- Parsing Integers 3:46
- Parsing Integers 1 objective
- Censoring Words - Using String Equality 4:51
- String Equality 2 objectives
- Censoring Words - Using Logical ORs 4:31
- Using Logical ORs and ANDs 5 questions
- Censoring Words - Looping Until the Value Passes 7:16
- Looping until the value passes 3 objectives
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Censoring Words - Using String Equality
4:51In this video, we will block a specific word from being used in our application.
All right, so let's block some words
from being allowed to be used.
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As a user of the Internet,
I am sure you've seen
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how not nice humanity can be
when hiding behind a keyboard.
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Let's do our part in attempting
to block this from happening.
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We'll take a few simplistic
approaches to the problem.
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But I'm gonna use these approaches to
introduce you to a few more commonly used
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tools in your Java toolbox.
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First, let's just block the word
dork from being used as our noun.
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We'll start with the same if and
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then exit pattern that we followed
blocking out our underaged users.
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We've already seen how methods can be
called on objects, like console, system,
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and integer.
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Now, here's something that might strike
you as a little strange at first.
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The strings that we've gotten back
from our users, they are objects too.
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And just like console, system, and
integer, they also have methods.
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Let's pop over the official
documentation and
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take a quick peek at what methods
are available to strings.
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I'll just do a quick search here for,
java String.
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And the fist result here,
is from the official Oracle documentation.
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And it's for the Java platform SE,
which is Standard Edition 7.
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We're currently running 8 in WorkSpaces,
but
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the thing that we're gonna look for
has been around forever.
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So let's just go in here.
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And we can scroll down here in this
documentation, very long documentation.
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And there's some bunch of ways
that you can construct the string.
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Here's the methods that are available.
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Let's scroll down a bit here.
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Again, what we're looking for
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is we're gonna see if noun is
actually equal to dork, all right?
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Cuz we wanna try to block that.
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So, is there anything
in here about equals?
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Here's something right here,
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equals compares the string
to the specified object.
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That sounds perfect.
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And it returns a boolean,
which remember, is true or false.
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And that's what we wanna kinda
use in our IF statement.
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So let's open that up.
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Let's take a look.
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So this is equals, and
it returns a boolean.
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And it compares the string to
the specified object that sounds perfect.
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Let's give that a go.
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So we'll go right here
after we have the noun.
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And we'll do another if statement.
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So we're gonna say, if, and
then we're gonna say the noun dot,
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cuz has methods, equals("dork").
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Okay, so that's our statement,
cuz that's gonna return a boolean.
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And that will be be true
if they've typed dork.
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And we'll open up our code block.
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We'll say, write out of the screen,
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That language is not allowed.
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Exiting.
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And we'll exit the program
using that System.exit.
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And we'll pass in 0.
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So we expected that.
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And we'll close the parentheses here.
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Okay, so I'm gonna save.
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And I'm gonna run and compile.
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I'm 20.
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I wish.
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My name's Craig.
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And what they wrote was big and dork.
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That language is not allowed.
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Exiting.
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Awesome it worked, we’re blocked.
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When I was looking at the documentation,
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I noticed that there is
also a See Also section.
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Let's go and and just check out and
ensure that we got the right one.
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The See Also, comparedTo,
and ooh, equals ignore case.
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And case there is talking
about letter case.
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So an upper case a or lower case a.
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Sounds like exactly what we want.
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Let's see that.
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Compares a string to another string
ignoring case considerations, perfect.
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Case strings are considered equal ignoring
case if they are the same length.
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Perfect, let's do that,
cuz that way if somebody yelled,
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DORK in all uppercase letters,
it would get past our censoring code.
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And I don't want that to happen.
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So, let's go ahead and
let's switch to that method.
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So we'll say, equalsIgnoreCase.
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Save, and let's go and compile again.
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Again, big.
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And then let's try to break it.
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We'll say DoRk.
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Awesome, great job.
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We stopped the haters.
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Excellent job!
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No one's gonna call me a dork now, but,
well, at least not on our program.
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I'm glad you got a chance to get slightly
familiar with the documentation.
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It can definitely be a bit verbose, but
you shouldn't let that overwhelm you.
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Remember, much like after a few
weeks of learning Spanish,
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you shouldn't expect to be able to open
the Spanish textbook to Chapter 15 and
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understand all that information.
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But what you should feel good
about is that some of those words
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are now starting to make sense, you've
learned a lot and you're doing great.
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We'll expand our approach
to the next video.
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But first, let's test out those new
string methods we just learned.
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