Getting Started

Okay. 0:00 Let's talk this through a bit. 0:01 You probably noticed that none of the stories told us about how our app 0:02 should be developed or even on what platform for that matter. 0:06 Since so far we've only gone over how to make console based applications 0:10 that seems like the obvious platform decision. 0:14 However if we do this right. 0:17 We should be able to reuse the game code that we write. 0:19 Since no matter how we end up playing the game that logic will stay the same. 0:22 We'll need to make sure that we separate the prompting and 0:25 displaying portion of the code from the game state and behavior. 0:29 This approach is called the separation of concerns and we'll touch on it here 0:33 lightly, and it will make a lot of sense after we get the code up and running. 0:37 But, the idea is this, we're building a console based application and 0:41 there is certain code that is needed for that to work. 0:45 But the game logic itself like the rules and 0:47 how you win, it pretty much stays the same. 0:49 By doing the separation, we could in fact end up using that game logic 0:52 code in like a desktop app, a mobile app, or even a web application. 0:57 So with that in mind let's build our structure out. 1:01 Let's build our game and prompter blueprints. 1:04 That separation should be enough to get us started. 1:07 Okay. So I've created a new workspace for 1:10 this part of the course, it has our starter file Hangman.java in it. 1:13 So first thing we should do is let's build our prompter class, 1:17 it should be pretty straightforward. 1:21 So I'm gonna make a new file, I'm gonna call it prompter.java. 1:22 Okay, so we wanna have a class. 1:27 And it needs to be named the same as the file that it's in, right. 1:30 So we're need to call it Prompter. 1:34 And let's open up the code block there. 1:37 Remember that's enough. 1:40 So we'll use this prompter object to do all of the IO or input output. 1:42 So we also need to separate out the game logic in it's own file here. 1:46 So we'll do new file, game.java. 1:51 Okay, and following the similar logic, we'll make a new class called Game and 1:54 I'm gonna open it up, and I'm gonna close it right away. 1:59 Give us some space and now, one thing that we know for 2:02 certain is that this class will need to know the answer to the puzzle, right? 2:05 So, let's say it's gonna be a string and answer. 2:09 Now, it should be private because that's how we always start things out, right. 2:14 We want to be private. 2:19 Okay, since a game is not really any good without an answer, 2:21 let's force the creation of a game to provide an answer. 2:25 We should use a constructor to do that. 2:29 So let's make a new public, and 2:31 a constructor Again has the same name as the class, so public game. 2:34 And we want to have it pass in an answer. 2:41 So we'll say string answer. 2:43 And then what we'll do is we'll take what was passed in and 2:46 set our private answer variable. 2:50 And to avoid naming collisions we'll say this.answer = answer. 2:53 That way, we know for sure that we're talking about 3:01 the instances field versus the argument that was passed in. 3:04 Great, that should be enough to define at the separation of concern. 3:08 So I'm going to save this, make sure that they're both saved. 3:12 I gonna come over to Hangman. 3:15 And let's make a brand new instance of our game. 3:17 So we'll say the type is game. 3:23 The instance of variable name is going to be Game and 3:26 we're going to say when you want a new Game. 3:29 That's gonna to call the constructor that we have there. 3:33 We're gonna pass in the answer. 3:34 Let's pass in tree house. 3:36 So let's do that. 3:38 I'm just gonna go ahead and compile and 3:39 make sure that we got all of our syntax correct. 3:41 And I just need to press to get in there to hangman.job and what that will do 3:43 is because game is in the same folder, it will try to compile all of this. 3:48 Well it'll at least compile Game. 3:53 Right. So I didn't compile Prompter because we 3:57 didn't access prompter yet. 3:59 But it did compile game. 4:01 So we know that's working. 4:02 So there's no errors. 4:03 And again, since this game class is in the same folder or package, Hangman 4:04 just found the proper class without us needing to specify where to find it. 4:09 Our separation of concerns looks great. 4:14 We have the prompter class which we used to deal with the IO and 4:15 the game class which will maintain the logic. 4:19 It's completely separated. 4:22 We also have the main executable file Hangman.Java where we'll use 4:23 instances of the prompter and the game classes. 4:28 Awesome. 4:31 All right. 4:32 Now that we have our main objects defined let's get to completing those stories. 4:32