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Running Your Code
6:58Let's explore Run Configurations and how to kick off our awesome projects.
So now that we know how to
get our code into the editor,
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let's take a quick look
at how to execute it.
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In WorkSpaces we built our application
by manually kicking off the compiler,
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Java C, which created Java class
files containing the byte code.
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Then we ran the Java executable and
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passed in the name of the class
that contained our starting point.
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You know, the static main method.
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Well I'm glad that we learned
how to do that it will help
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demystify the compilation and
running process that you are about to see.
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The IDE does all that and more.
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Ready to learn how?
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Let's go take a look.
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Okay so the first thing to remember is
that you can have multiple modules and
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therefore it's possible that you
can have static main methods in
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any of those files that you want to run.
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And there's no real way that the IDE
could possibly know which file
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you wanna execute.
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So the idea in running something is to
first find the file that you wanna run.
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So, I know that our file that we
ran before was called Karaoke.
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And I know it's a little confusing
it's the Karaoke project.
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It's the Karaoke file.
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There's also a karaoke machine.
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We should probably rename
that in the future sometime.
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For now let's open it.
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And let's say that I didn't want to
use the mouse to click over there.
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If I come over here and
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press double shift, there's a great
tool called Search Everywhere.
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I'm just going to start typing karaoke.
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There it is, classes, I'm going to choose
that and I'm going to press Enter, boom.
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There's our Karaoke file, great.
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This is what I want to run, right?
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Remember this goes and
starts every thing off.
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So since I have it open,
I'm going to go to the run menu, and
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I'm just going to choose run here.
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Now it's just double-checking
what I meant, and
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it's gonna do this here, Karaoke,
and I'm gonna click this.
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It's gonna go ahead and
it's gonna build the file.
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After it's built,
we'll take a look at how it got ran.
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Okay, so it's gonna pop up a new
window here called the console.
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And here, you'll see that the program's
actually running and it's waiting for
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our input.
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Here's the program that got kicked off and
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I just kinda wanna show you all
the way over here to the end.
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That's kind of a crazy set up, but
it's running basically what we did,
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but it's wrapping it in this IDE magic and
what that does is it allows us to.
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Type into this window, and
it allows System.out to come into here.
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So right, so System.in is coming in and
capturing it, and it's wrapping it.
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But it's still passing
at this parameter here.
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So let me scroll all the way back.
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Okay, cool.
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So, what do we wanna do?
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Let's choose a song to sing.
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Right?
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Let's choose U2.
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And I still haven't found
what I'm looking for.
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Okay, great.
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So it's pretty cool right?
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Now the bummer is that in
a few of our apps we used
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System.console which is specifically
made for console apps by the Java team.
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So the bad news is.
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And you might have heard some
chatter about this in the forum.
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The don't work so well in this redirected
IO model that most of these IDEs use.
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Right?
So the way that they're writing to
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the window and reading from the window.
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So currently there are bugs filed in
almost all of the popular IDEs that I saw
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to support the System.console bug,
but the big problem is,
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is that console is marked final.
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Remember that can't be changed.
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So it's pretty hard for
these IDE maintainers to get things right.
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So you can't really blame them.
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Maybe by the time you're watching
this they'll already have it fixed.
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But if not, use the tricks that we use in
this Karaoke app of using System.out and
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System.in as opposed
to System dot console.
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I've included some notes about
the problem in the teachers' notes.
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Now, since we've run this
once what happened was it
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created a run configuration.
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So you'll see here in the menu
that it has a Run Karaoke.
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Let's go ahead and click that again.
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So it's kicking it off again, and one
thing that I really wanted to point out is
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that we left our first application
still running over here, and
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there's another one running.
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So, it's running two.
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And that's totally fine, but
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you might forget and
get a whole bunch of these going.
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So it's important to know that there's
a little run menu over here, and
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you can stop things.
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So let's stop that Karaoke.
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Let this process finish,
and we'll come over here.
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The other thing you could do is say Close,
or Close Tab or Close All Tabs.
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And this is a pretty common thing to see.
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The Karaoke is running,
we're just gonna say to disconnect and
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terminate the process.
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Boom, and now, well,
our menu's gone from down there.
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Okay, so this is the runbar up here.
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You'll also see that
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all the different configurations that
got built will be shown in here.
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So we just built that configuration for
Karaoke so it's in here.
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So, let's go ahead and
open up that configuration.
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Okay, cool.
So these are the settings for it.
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You can set options for
each time that the program runs.
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So remember in our Hangman app,
we passed the name of the puzzle.
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That's what this Program
arguments field is here.
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The Working directory is what
is set from where things start.
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So if you remember,
that's why we dropped the songs.txt.
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Right into the content root because
this is the content root right.
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Karaoke, content root.
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So, that's where things work relatively.
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I don't know if you remember
exactly where that is but
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I want to show you where we're doing this.
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So I know that we're
doing this thing here.
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Called import from songs.txt.
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So let's say that we didn't know
where that SongBook def was.
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But we knew that the function
was called import from.
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So you can also sort modules right.
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So if I go import from and I hit it.
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It will go right to where it was at.
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And let's see.
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So it says a new import stream
reader on the fileName and
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that was songs.txt that we passed in and
since.
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This thing works relatively.
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It's working from the working directory,
which is right here.
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Cool right?
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Okay, so let's flip back really
quick to that configuration.
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So I'm going to click this up here and
choose that Configurations.
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I want to show you one more thing
because it's kind of buried and
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I've seen some questions about this so
I just want to make sure I point it out.
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Logging is a great tool that
is available in Java and
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Java has a great logging system.
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It allows you to categorize and
place entries of different severities and
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lets you know what's happening
during your application.
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And maybe you don't want to show users
what's happening during your application,
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but you do want to have
logs of what was happening.
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So, there's a tab over here that says
Logs and you can configure them here.
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You can save everything that
happened to a console to a file.
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So, that's kind of helpful
through debugging,
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if you wanted to get back to it later.
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And there's also the ability to
show the console when it changes,
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which is also pretty nice.
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So the last thing that I want you to
remember here is that you can have
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multiple modules with run configurations,
and just remember that pressing
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this run button here will run
whatever is in this list here.
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So this is Karaoke.
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So if I press play,
it will run that specific configuration.
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Great, all right.
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So now we can navigate around our
file structure, and build and
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run our application.
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There is a ton more of this IDE you can do,
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and much more than I could
possibly show you in this course.
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Let's spend a little time learning
how to figure more out, and
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also let me show off a few
of my favorite tricks.
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