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Let's now go ahead and write a Java program in Eclipse.

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So let's just go ahead and launch eclipse.

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It's just double click this icon here.

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So first thing eclipse wants us to do is it wants us to select something as a workspace or we need to

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create a new workspace workspace basically represents our application.

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So it's the place where we on our source code gets stored.

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So within a workspace we create a project and the project has this our source code and the workspace

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and how more than one projects do.

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And those projects can be interrelated.

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Usually it's if there are multiple projects that are usually interrelated.

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So there is already a workspace here but let's just go ahead and create a brand new one.

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So let's browse a look see dry within C-Drive let me create a new workspace called Jayati to new folder

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which is short for Jawa and.

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OK.

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OK here now eclipse would launch a new workspace.

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Now if we go into our explorer let me refresh this as you can see it has created a new folder on my

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C drive.

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Congi ID.

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So it's basically the workspace.

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And within this workspace all the source code that we write in eclipse would get stored here.

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OK so the project get stored here.

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The project can also get stored there is an option to also write the project extra Netaji ID extra to

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the workspace and then get to the workspace.

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That option is also there.

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OK.

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So let's just go ahead and create one project.

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So let's just close this welcome screen.

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So before creating our project I would like to just take a moment to talk about something cardless gelap

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perspective about prospectives perspective is basically it.

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It basically represents a view of your project.

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The project that you create.

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It's a view of your project.

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OK.

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So here there is the Djala.

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Each prospect do.

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So that's getting shown by default if you want to see it look at other perspectives.

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You just need to click on this icon called open perspective and hit all the different perspectives that

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Eclipse provides.

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And here is Ajalon one on here is a debug sort of just click on debug.

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So it just brings a different view of the project and you can also create Java.

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Let's just select Java and debug one table.

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You know when we are covering the debug debugging listen we will be looking at that interface.

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Ok now this is a different interface.

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And so as we are selecting them they get laid out here and the top and we can switch across also.

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So that's the perspective.

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So basically it represents a view of your project.

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Let's just look at the Java aspect do so within the Java perspective like you have these different frames

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and each frame we call it as a view.

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So here you have the package Explorer View and package Explorer have you as a name suggests it is used

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for exploring your projects your packages.

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So within Java library within the Java code that we create usually we have packages and within the package

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just be how classes are if we select a particular class then the source code of that class show up shows

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up here.

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This is the textedit of this is the editor of view.

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And here you know if you under if you're under a particular class file then the output of dight will

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be shown here and you will get opened.

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It's called as a console you know it gets open here and we'll be able to see the output.

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Let's not worry about these other views here.

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So these are the three main news that we have.

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That's the perspective on the views.

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So let's just go ahead and create a new project.

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We are going to file new.

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It's quick on this job project.

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It's quoted as Eclipse best and we are saying that use the default location which means that it's going

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to get created an NGO idea itself and the database and the execution environment that GRV that we are

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using is Jawa as eat and we are saying that creates separate folders for sources unclassified.

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OK so you'll have separate folders for both source code and the compiled classifieds.

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OK hit next.

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OK so as you can see a new project has got created here and here we have something called Jawa Bell

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settings.

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This is nothing but you know all the libraries that this particular code that we are going to write

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is going to be shown here and we can add those libraries here.

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But when this is called a Java belled settings on we will get back to that later in the next lesson

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.

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That's it.

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And I just had to finish and if you see you'll have a folder called S R C and we are depending on this

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library in Java.

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I see one point eight.

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Now let's just let's just look in the explorer 2.

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So if you're going to JRD you can see there is a new folder called Eclipse disk that God created.

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Click on that you will see SIRC.

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So in this ARCI for you go to any source code that we cleared and gets stored here.

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And once it gets compiled the compiled files will be stored in the bin folder.

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Let's go ahead and create a class.

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So let's just right click on the project and let's send.

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And let's click on class Let's name the class as Hello world.

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OK.

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So modify this public superclasses dollar dog Langhart object and which method set up.

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So would you like to create which just select this so that the main method would be auto created and

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that's it said we can just leave it as it is.

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Heck finish this work.

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Create a new class as you can see the font sizes.

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It's small.

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So let's just add logic.

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So for DAC we can go into the window and there is something called preferences.

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Let's go ahead and hit preferences and preferences show you how all these options here.

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And let's just select the first one with just Gendron and Biton gender you can see that there is this

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thing called us once.

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OK let's click on appearance and that is colors on phones.

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Let's click on colors on fonts on within colors on fonts.

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Since we are dealing with Jellico Let's go into Java and let's head this thing edit a text font.

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OK so let's just click that and you can see that we have these different font sizes let's select 16

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for example.

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OK apply.

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OK.

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Now the font size has increased.

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OK.

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Now let's put some statements here.

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Let's put this out statement system not out just typing this out.

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Can crawl space that for being up this thing and you could click that you know the court is auto generated

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.

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Now let's just put them.

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Hello here.

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So in order to run this all we need to do is right click see Iran as unselect this Java application

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option are the simpler way is to simply click on this button here or on us.

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Let's just click that as you can see the console view has open now and it's showing the output here

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.

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Now by any chance if you happen to believe this here by me you know accidentally then all you need to

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do is once again go back in big window and here you have show you show which is nothing but it shows

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all the views that we have in this perspective.

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OK.

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So the one the one the view which we lost is the console.

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So it's quick on that and it's back again with the output that was there earlier.

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That's the console you.

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Now let's go ahead and put some statements here.

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So let's say long a was 42.

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Now let's assign it to an I.

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Now as you can see it is giving us a compilation error.

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So you see this that red icon here it says Type mismatch because you cannot convert from long to and

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.

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OK.

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Now when I save it it also gets shown here in problems view.

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So if I expand it I can see the same message here.

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Now let's just go ahead and fix this.

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So let's put the typecast here and it's fixed.

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So the error of the compassion has gone back to showing another yellow symbol here icon.

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It's it's just a warning.

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It says that the blue of the local variable is not used.

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Right because we are not using the value I it is being used here but I is not yet used.

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So it's just a warning it's not a compiler error.

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And the same warning also gets shown here and.

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Yeah.

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So that's sub-Arctic like how you were running or you just click on this button here and you run it

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.

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That is one other thing I wanted to that is going to bring reference's.

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So we look up how to change the font.

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And there is also this option called editors if you go in to editor text editor here and you have some

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other options like showing the line numbers by default because it has been selected here if you do this

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and you say I applied.

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So the line numbers would go heavy but we does I think really nice to have the line numbers so let's

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just put them back and there are also other options here.

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You can check them out and play around with them.

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Also here in the package explorer we can explore the classes that we created.

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So here is a Hollywood.

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And here is a method that we created.

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So if there were more methods they would have shown up here under under the class I find this is the

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package name.

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So when we created the class it picked the project name as the package name itself.

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So we could have given a different name but we just let that be false as it as it is.

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And here in the main method.

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So if you're for the print alone if you just haul it over it here.

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So I chose the Java doc off that particular print method.

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So it allows us to look at the description of the matter.

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OK.

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And here is the class system and it says something about the system so it's a dollar Dawk for the class

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itself.

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Now let me just go back to here today Explorer.

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So we this is the workspace and this is this odyssey for gold which has the source code.

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Now if we go into Ben.

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So it has the class files.

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The classifieds that Gajah undeterred will be here.

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So this is a package an eclipse d'Este and within Eclipse's we have the Holloway got class file.

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So that's about it