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Alright, so let's go ahead 2

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and dive in to Eclipse and we're gonna run 3

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some demos here on Bean Scopes. 4

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We'll take a look at those singleton scope 5

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and a prototype scope and we'll see 6

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all of this code running in action 7

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and I don't know, just get a good feel for it. 8

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The first thing we wanna do is, 9

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copy our application context file. 10

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We're actually going to create a new version of it, 11

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so we'll take this existing application context, 12

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we'll just do a right click and choose copy 13

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and then, we'll simply paste it, 14

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so we just do a right click and we choose paste 15

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and this new version, we'll give it a new name here. 16

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I'll call it, beanScope-applicationContext.xml 17

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and so, with these spring config files, 18

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you can really give them any name that you want. 19

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Your project can actually have multiple config files 20

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and here you simply reference the one that you want, 21

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so you can call it anything, fubar.xml if you wanted to, 22

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as long as you reference it with that name. 23

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Anyway, I have my beanScope-applicationContext.xml, 24

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now let's go ahead and bean it up, 25

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let's go ahead and open this file 26

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and what I wanna do is, I just clean it up. 27

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There's some lines in here that I want to delete. 28

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I'll select lines 10 and 11, I'll highlight those 29

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and I'll delete these lines because we're 30

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not going to use any of the property placeholder stuff here. 31

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I'm moving down a little bit further 32

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and I'll also remove that bean for myCricketCoach, 33

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so I'll just highlight the lines 24 through 34 34

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and I'll actually delete those lines 35

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and I'll just clean up some of this white space, 36

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move up and let's do a little quick check point, 37

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so in this config file that we just created, 38

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beanScope-applicationContext.xml, 39

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these are the only two entries that we should have 40

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inside of here for beans, so we'll have our FortuneService 41

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and we'll have our Coach, that points to our TrackCoach 42

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and that's all we should have, at this point. 43

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Now, by default, since we didn't specify 44

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a scope for our track coach, well, what's the scope? 45

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Well, it's singleton right? 46

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Basic information we've learned so far, 47

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so it'll simply be a single bean, 48

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now, everyone will reference when we run our application. 49

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Let's go ahead and create another main app, 50

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I'll call this guy, BeanScopeDemoApp.java, 51

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so I'll just do a right click, I'll say, new class 52

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and the actual name of the class again, BeanScopeDemoApp 53

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and I'll also go down and I'll check the box there 54

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for the public static void main, 55

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because I'll have a main method, 56

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just a little separate demo app that I'll use for 57

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testing out this scoping stuff. 58

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Alright, okay with all that stuff, hit, finish. 59

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Alright, so we have a very simple bean scope demo app. 60

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I'll just move in here and I'll just remove the 61

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auto-generated stuff and I'll write some quick comments 62

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here, as well as what I need to do. 63

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This is kinda, you're getting really used to this now, 64

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the first thing we need to do is, 65

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load the spring configuration file 66

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and then, simply retrieve beans from the spring container. 67

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Alright, that's kinda the game plan, 68

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let's write the code right here 69

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and you should probably know most of this now, 70

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from memory because you've seen this a lot 71

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so this is good practice, this is how you can really learn 72

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the technology, just by repeating it 73

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over and over again, just like a sport, 74

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practice, practice, practice. 75

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Let me go ahead and use that ClassPathXmlApplicationContext, 76

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I'll just do a copy paste, I say, new 77

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and I give the actual name, so this is gonna be 78

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the actual name of my new configuration file 79

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that we just created, so that's 80

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the file that we created called, 81

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beanScope-applicationContext.xml, 82

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let me go ahead and fix up the imports right here. 83

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I'll just hover over and say, import that given class, 84

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looks good and there we go, so yeah, 85

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that's our new config file that we're reading in here, 86

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beanScope-applicationContext.xml 87

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so again, you can have as many config files 88

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up here as you like for your project, 89

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simply load the appropriate one. 90

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Also, if you have multiple, you simply give 91

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a common denominated list, you can load in 92

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multiple configs if you wanted to. 93

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Alright, let's keep it simple for now. 94

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Now, let's go ahead and get some white space 95

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and let's go ahead and retrieve the bean from the container. 96

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I'm actually gonna retrieve two beans, 97

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so I'll start off with the first one here. 98

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I'll say, Coach theCoach = context.getBean, 99

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I give the name, which is, myCoach 100

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and then I give the interface, Coach.class. 101

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Looks good, and also you can just copy paste this line, 102

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for the second reference, so I'll 103

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just do a paste on that one, instead of the coach, 104

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I'll call it alphaCoach and everything 105

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else here stays the same, so basically, 106

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this is the code here for retrieving 107

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the bean from the spring container. 108

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Right now, it's a singleton, so 109

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we should get the same reference 110

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and we'll actually write some code in a second 111

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to show us the reference, but I'll kinda pause for now. 112

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In the next video, we'll write more code 113

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to print out the results of this reference. 114

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I'll see you in the next video.