1 00:00:00,280 --> 00:00:01,480 The Java community and 2 00:00:01,480 --> 00:00:06,200 ecosystem consists of a whole slew of acronyms and, unfortunately, 3 00:00:06,200 --> 00:00:09,620 if you're gonna follow along, you're gonna need to get familiar with them. 4 00:00:09,620 --> 00:00:15,150 We're about to start on a long line of them so try not to let it overwhelm you. 5 00:00:15,150 --> 00:00:17,710 I will make sure that they're in the teacher's notes every time I 6 00:00:17,710 --> 00:00:18,290 introduce one. 7 00:00:19,390 --> 00:00:21,050 Remember to check your video controls and 8 00:00:21,050 --> 00:00:25,450 slow me way down if you start to feel lost. 9 00:00:27,050 --> 00:00:28,570 Almost every programming language or 10 00:00:28,570 --> 00:00:32,210 platform provides you with tools to do work locally on your computer. 11 00:00:32,210 --> 00:00:37,020 These tools are usually grouped under the title Software Development Kit, or SDK. 12 00:00:38,060 --> 00:00:40,061 They are also sometimes referred to as devkits. 13 00:00:42,101 --> 00:00:45,690 The Java language has an SDK, and it's made up of many things, 14 00:00:45,690 --> 00:00:50,560 application servers, debuggers, code samples, and documentation. 15 00:00:50,560 --> 00:00:55,280 There's an extended subset of this SDK that is known as the Java Development Kit, 16 00:00:55,280 --> 00:00:55,850 or JDK. 17 00:00:57,120 --> 00:01:02,160 When the term JDK is used, we are referring to this subset, the Java SE, or 18 00:01:02,160 --> 00:01:04,160 Standard Edition, Development Kit. 19 00:01:06,570 --> 00:01:08,770 You've used a couple of tools already out of the JDK. 20 00:01:08,770 --> 00:01:12,840 The Java documentation provides a great overview of the JDK. 21 00:01:12,840 --> 00:01:13,660 So let's go check it out. 22 00:01:15,290 --> 00:01:15,920 Now remember, 23 00:01:15,920 --> 00:01:20,160 I warned you about the upcoming acronyms so let's not get overwhelmed. 24 00:01:20,160 --> 00:01:23,560 I just wanted to show you a couple things in this really nice graphic. 25 00:01:23,560 --> 00:01:25,990 So you'll see here this is the entire JDK. 26 00:01:27,360 --> 00:01:29,550 And up here a couple tools you're familiar with, right? 27 00:01:29,550 --> 00:01:34,500 There's Java and there's javac, and you'll get familiar with the rest of these. 28 00:01:34,500 --> 00:01:39,970 And in here, is what is known as the JRE, the Java Run Time Environment. 29 00:01:39,970 --> 00:01:41,600 It contains libraries that we've been using. 30 00:01:41,600 --> 00:01:43,340 See, here's the collections, right, 31 00:01:43,340 --> 00:01:47,370 and there's others that we'll continue to explore over our Java adventures. 32 00:01:47,370 --> 00:01:48,900 Now the Java language is up here. 33 00:01:48,900 --> 00:01:52,310 This is where we'll be using the ifs and the whiles and that sort of thing. 34 00:01:52,310 --> 00:01:57,400 So the main thing to note here is that you can actually have the JRE all by itself. 35 00:01:57,400 --> 00:01:59,980 And some people ship their applications with just the JRE, 36 00:01:59,980 --> 00:02:03,090 without actually having their users install the JDK. 37 00:02:03,090 --> 00:02:07,540 But, since we're developers, we'll need the JDK for sure. 38 00:02:07,540 --> 00:02:12,530 So remember, when we go to download this we want the JDK and not the JRE. 39 00:02:12,530 --> 00:02:15,620 I put a link to this wonderful graphic in the teacher's notes. 40 00:02:15,620 --> 00:02:18,330 Feel free to click around, these are all links. 41 00:02:20,460 --> 00:02:22,650 All right, so let's go over that one more time. 42 00:02:23,950 --> 00:02:28,370 The Java Platform provides two main software products, the JDK or 43 00:02:28,370 --> 00:02:33,220 the Java SE Development Kit and the JRE, or the Java SE Runtime Environment. 44 00:02:34,510 --> 00:02:37,460 The JDK contains the JRE. 45 00:02:37,460 --> 00:02:42,790 The JRE contains the Java SE API, or application programmer interface. 46 00:02:42,790 --> 00:02:47,566 The API is the libraries like the collections framework, like the list, set, 47 00:02:47,566 --> 00:02:50,380 and map that we've been using. 48 00:02:50,380 --> 00:02:53,720 Those libraries are also sometimes referred to as 49 00:02:53,720 --> 00:02:55,730 the Java Class Library, or JCL. 50 00:02:57,120 --> 00:03:01,710 When we talk about the JDK, we will be talking about the official Oracle JDK. 51 00:03:01,710 --> 00:03:04,580 However, you should know that this is an open platform, and 52 00:03:04,580 --> 00:03:07,200 there are numerous JDKs available. 53 00:03:07,200 --> 00:03:10,661 I've linked to a list of them in the teacher's notes. 54 00:03:10,661 --> 00:03:15,950 Phew, I told you, there were TMA, too many acronyms. 55 00:03:17,780 --> 00:03:21,840 One very important feature of the JRE is something we haven't touched on yet. 56 00:03:21,840 --> 00:03:24,360 Of course, it's another acronym. 57 00:03:24,360 --> 00:03:27,610 It's the JVM, or the Java Virtual Machine. 58 00:03:27,610 --> 00:03:30,030 Let's learn a bit more about that right after this quick exercise.