1 00:00:01,780 --> 00:00:05,810 Welcome back! In this step, we would look at starters. 2 00:00:06,080 --> 00:00:12,560 We would look at a couple of example starters. Spring Boot starter web and Spring Boot starter JPA. 3 00:00:12,780 --> 00:00:18,030 If you open up the pom dot xml of the project that we have created earlier, you would see 4 00:00:18,030 --> 00:00:20,620 that it's using Spring Boot starter web. 5 00:00:20,700 --> 00:00:23,950 How did it use Spring Boot starter web? 6 00:00:24,030 --> 00:00:28,240 That's because we configured a dependency on web in here. 7 00:00:28,440 --> 00:00:36,570 So if I open that up and go to the pom dot xml, youd see that Spring Boot starter web is configured in 8 00:00:36,580 --> 00:00:37,190 here. 9 00:00:37,420 --> 00:00:42,820 So this Spring Boot starter web is the preferred stater for Spring Boot to develope web applications 10 00:00:43,210 --> 00:00:46,350 as well as RESTful web services. 11 00:00:46,360 --> 00:00:53,680 So if I go control and hover over it or command and hover over it and click open pom dot xml for Spring Boot 12 00:00:53,680 --> 00:01:00,140 starter web you would see that it defines varied kind of dependencies. 13 00:01:00,170 --> 00:01:01,710 So what does it really define? 14 00:01:01,870 --> 00:01:09,910 Let's look at it. When we run the application, we were automatically using Tomcat. Thats because of this Spring Boot 15 00:01:10,580 --> 00:01:11,140 starter Tomcat. 16 00:01:11,560 --> 00:01:13,390 If you look at Spring Boot starter web, 17 00:01:13,540 --> 00:01:16,720 it contains a dependency on Spring Boot 18 00:01:16,740 --> 00:01:22,640 starter Tomcat and that's how the application is automatically running in 19 00:01:22,660 --> 00:01:30,260 Tomcat. The other things which you would seen here are Spring web and Spring web MVC. Spring MVC 20 00:01:30,260 --> 00:01:37,090 as you would know is this Spring MVC framework. If I add in a Spring Boot starter web, I automatically get Spring 21 00:01:37,090 --> 00:01:40,730 MVC, I automatically get validation. Validation - 22 00:01:40,750 --> 00:01:45,850 the default implementation for Java validation API is hibernate validator. 23 00:01:45,850 --> 00:01:49,810 So I get that as well and I get Tomcat. 24 00:01:50,020 --> 00:01:57,200 And, also I get the starter JSON. Starter JSON is more for RESTful web services. 25 00:01:57,280 --> 00:02:05,320 We saw that when we actually invoke the RESTful web service, the conversion to JSON automatically happen. If 26 00:02:05,320 --> 00:02:07,030 you actually looked at our code, 27 00:02:07,180 --> 00:02:12,550 We just returned the bean back. So in the booksController, what we're doing is we are just returning a 28 00:02:12,550 --> 00:02:13,960 list of beans back. 29 00:02:13,960 --> 00:02:19,710 How does it automatically convert it to JSON? That's done through this starter. 30 00:02:19,950 --> 00:02:25,000 The starter JSON brings in the JSON into the picture. 31 00:02:25,000 --> 00:02:32,590 Basically when you look at all starter projects, they have a set of dependencies that are already defined. 32 00:02:32,980 --> 00:02:37,900 And these dependencies are automatically provided to our project. 33 00:02:37,900 --> 00:02:44,590 So when I add in Spring Boot starter web, I get all these dependencies. So you'd see that I'm getting 34 00:02:44,620 --> 00:02:49,030 Jackson for handling all the JSON stuff. You'd see that I'm getting Tomcat. 35 00:02:49,030 --> 00:02:56,280 So that I can the application in Tomcat. I'm getting hibernate validator and validation API for doing the validation. 36 00:02:56,320 --> 00:03:03,430 Im getting this Spring framework because I have a dependency on Spring web and that could have dependency 37 00:03:03,430 --> 00:03:05,140 on Spring framework. 38 00:03:05,560 --> 00:03:14,400 And, also I would get the logging frameworks as well because the logging frameworks are by default defined 39 00:03:14,460 --> 00:03:15,810 in the Spring Boot 40 00:03:15,870 --> 00:03:20,250 starter. So Spring Boot starter is one of the dependencies in Spring Boot starter web. 41 00:03:20,530 --> 00:03:22,960 So if you open up the pom dot xml for it, 42 00:03:22,990 --> 00:03:25,680 So this is the default starter. 43 00:03:25,780 --> 00:03:32,590 This is where everything inherits from. So any starter that you would use in Spring Boot, it inherits from 44 00:03:32,590 --> 00:03:37,480 Spring Boot starter and you would see that these are the dependency and Spring Boot framework. 45 00:03:37,490 --> 00:03:39,990 This has a dependency on Spring Boot auto configure. 46 00:03:40,150 --> 00:03:42,260 That's how we get auto configuration. 47 00:03:42,280 --> 00:03:46,260 This has a dependency on Spring Boot starter logging. 48 00:03:46,360 --> 00:03:47,840 That's how we would get logging. 49 00:03:47,950 --> 00:03:52,120 And we have a dependency on Spring core as well. 50 00:03:52,210 --> 00:03:56,160 YML is one of the configuration languages that Spring Boot supports. 51 00:03:56,170 --> 00:03:58,930 So we also have snake YML in here. 52 00:03:59,020 --> 00:04:05,660 Thing about Spring Boot starter web is once it brings in all these dependencies, what would kick in? Auto 53 00:04:05,710 --> 00:04:07,150 configuration would kick in. 54 00:04:07,150 --> 00:04:12,640 Because the spring web MVC contains dispatcher servlet. So automatically dispatcher servlet would 55 00:04:12,640 --> 00:04:14,280 be configured. 56 00:04:14,280 --> 00:04:20,230 That's done by the Spring Boot auto configure. Thats the auto configuration which we talked about earlier. 57 00:04:20,950 --> 00:04:25,890 Spring Boot starter web is one of the starter. The other starter you can see in here is Spring Boot starter 58 00:04:25,980 --> 00:04:32,050 test. Spring Boot starter test enables you to write unit test and integration tests as well. 59 00:04:32,380 --> 00:04:38,660 So if I go to the pom dot xml in here, you would see that it has a definition on spring boot test. 60 00:04:38,860 --> 00:04:46,030 It has a definition on the auto configured for Spring Boot test and it has dependencies on Junit framework. 61 00:04:46,500 --> 00:04:47,530 AssertJ. 62 00:04:47,590 --> 00:04:54,870 And also you have Mockito. Mockito is the default mocking framework that comes along with Spring Boot. 63 00:04:54,880 --> 00:05:00,040 A combination of AssertJ and Hamcrest are awesome to write great matches. 64 00:05:00,100 --> 00:05:05,080 And you also have a dependency on the spring test framework which is useful in writing unit tests for 65 00:05:05,080 --> 00:05:05,980 spring. 66 00:05:05,990 --> 00:05:11,500 So until we looked at a couple of starters which are Spring Boot starter web and Spring Boot starter 67 00:05:11,540 --> 00:05:12,270 test. 68 00:05:12,430 --> 00:05:18,520 Other than that, another important starter which is frequently used as a Spring Boot starter JPA. 69 00:05:18,580 --> 00:05:28,570 If you know JPA, JPA is kind of the interface for hibernate. So JPA defines how ORM applications or ORM frameworks 70 00:05:28,690 --> 00:05:36,530 should work. ORM is object relational mapping. Let's now add in a dependency on Spring Boot starter JPA. You 71 00:05:36,530 --> 00:05:40,300 would see now that there would be a lot more Maven dependence which would come in. 72 00:05:40,310 --> 00:05:42,600 Actually, it's Spring Boot starter 73 00:05:45,560 --> 00:05:45,920 data JPA. 74 00:05:46,040 --> 00:05:53,120 So now we have hibernate core, hiberante JPA. We have javax transaction api, hibernate common annotations. 75 00:05:53,210 --> 00:06:00,530 You have spring data, spring data JPA, spring ORM, spring tx and a lot of such dependencies 76 00:06:00,690 --> 00:06:05,310 come in. That's because of the Spring Boot starter JPA. 77 00:06:05,450 --> 00:06:11,480 So if you open up the pom dot xml for spring boot starter JPA then you would see all of the dependencies 78 00:06:11,480 --> 00:06:17,540 that are listed down. So this has a dependency on spring boot starter AOP, starter JDBC, hiberante transaction 79 00:06:17,570 --> 00:06:19,920 API and spring data JPA. 80 00:06:19,940 --> 00:06:26,150 So all this jars you'd get. As soon as I add in a spring starter data JPA, I would get all these 81 00:06:26,360 --> 00:06:27,590 things for free. 82 00:06:27,590 --> 00:06:33,260 One of the things you need to remember is if you are a starting programmer or this is the first time 83 00:06:33,260 --> 00:06:39,470 you are looking at Spring Boot, a lot of things might be confusing to you. Especially because we are referring 84 00:06:39,470 --> 00:06:42,110 to so many different terminologies. 85 00:06:42,260 --> 00:06:49,190 Spring Boot solves problems for wide variety of frameworks. So there are a lot of terminologies that 86 00:06:49,190 --> 00:06:51,830 come into picture when we talk about spring boot. 87 00:06:51,830 --> 00:06:56,570 So if you're not able to understand any of these terminologies do not worry at all. 88 00:06:56,760 --> 00:07:03,200 Over the course of this course and also over the course of your next few years, you'll learn sufficiently 89 00:07:03,200 --> 00:07:07,490 enough so that those terminologies become really clear for you. 90 00:07:07,550 --> 00:07:13,250 The idea for you is to understand the big picture of what Spring Boot does. 91 00:07:13,310 --> 00:07:18,080 Spring Boot is now one of the most popular frameworks to develop. 92 00:07:18,140 --> 00:07:25,220 micro services. The idea behind the whole set of these steps is to give you a flavor of Spring Boot in 93 00:07:25,220 --> 00:07:27,560 a wide variety of scenarios. 94 00:07:27,560 --> 00:07:31,570 If you are not able to understand a couple of scenarios that's not a problem at all. 95 00:07:31,610 --> 00:07:34,170 With that disclaimer, let's end this step here. 96 00:07:34,250 --> 00:07:37,180 And I look forward to see you in the next step.