1 00:00:02,220 --> 00:00:05,800 Until now, we looked at some of the basics of Spring Boot. 2 00:00:06,110 --> 00:00:12,260 And before we go any further, I think it would be great if you can clearly separate what are the differences 3 00:00:12,260 --> 00:00:16,080 between Spring, Spring MVC and Spring Boot. 4 00:00:16,190 --> 00:00:23,180 I think having great clarity on that would be really wonderful. Spring Boot, Spring MVC and Spring. 5 00:00:23,330 --> 00:00:24,410 How do they compare? 6 00:00:24,470 --> 00:00:28,630 That's basically what we would want to answer in this specific step. 7 00:00:28,640 --> 00:00:34,880 Actually, by the end of this, you would understand that Spring, Spring MVC and Spring Boot have their 8 00:00:35,000 --> 00:00:36,300 own roles. 9 00:00:36,310 --> 00:00:38,860 They are not really competing for the same space. 10 00:00:39,050 --> 00:00:44,250 They solve really different problems and they solve them really really well. 11 00:00:44,270 --> 00:00:47,570 So what's the core problem that Spring framework solves? 12 00:00:47,570 --> 00:00:56,960 Think about it. The core problem Spring framework solves is testability. If you don't define proper dependencies 13 00:00:57,050 --> 00:01:00,280 then your applications are not testable. 14 00:01:00,290 --> 00:01:09,170 The most important feature is dependency injection. The core of Spring framework is the IOC - inversion of control. 15 00:01:09,330 --> 00:01:14,940 Spring framework takes control of all the beans and their dependencies. 16 00:01:15,170 --> 00:01:22,550 That's basically what the Spring framework cares about. Spring framework is all about defining your beans, putting 17 00:01:22,550 --> 00:01:28,900 your at component, putting your at service and things like that and also defining your dependencies 18 00:01:28,960 --> 00:01:34,670 at auto wired and things like that and also defining how to find your beans. 19 00:01:34,700 --> 00:01:42,680 Components scan for example. Thats basically the core problem that Spring framework solves. Spring framework solves 20 00:01:42,710 --> 00:01:46,030 the problem of dependency injection. 21 00:01:46,040 --> 00:01:53,210 It helps you to build loosely coupled applications. Loosely coupled applications can be easily unit 22 00:01:53,210 --> 00:01:54,020 tested. 23 00:01:54,170 --> 00:02:00,140 If you look at this example, you'll see that welcome service instance is directly created in here. 24 00:02:00,140 --> 00:02:06,170 This is tightly coupled. The welcome controller is now tightly coupled to the welcome service. 25 00:02:06,450 --> 00:02:13,470 However, if you do Dependency Injection properly then you would auto wire it in. 26 00:02:13,490 --> 00:02:21,140 You can use frameworks like Mockito and Mock Spring MVC to replace this service with a mock and unit 27 00:02:21,170 --> 00:02:21,590 test 28 00:02:21,590 --> 00:02:27,550 this controller. Thats the main problem that Spring framework solves. 29 00:02:27,560 --> 00:02:33,340 Other than that, Spring framework also solves a few other problems like duplication and that's basically plumbing 30 00:02:33,340 --> 00:02:34,140 code. 31 00:02:34,200 --> 00:02:40,080 So if, lets say you are using JDBC then you needed to write a lot of boilerplate code. 32 00:02:40,100 --> 00:02:47,600 Try, catch, exception and all that kind of stuff. That's not needed when you use any of the things that 33 00:02:47,600 --> 00:02:51,410 are based on the Spring frameworks, Spring JDBC or Spring JMS. 34 00:02:51,410 --> 00:02:54,380 You don't really need to do that kind of stuff at all. 35 00:02:54,380 --> 00:03:00,590 The other thing with Spring framework solves was providing good integration with other frameworks. So Spring 36 00:03:00,980 --> 00:03:03,930 had good integration with Hibernate ORM. 37 00:03:03,960 --> 00:03:05,640 iBatis for object mapping. 38 00:03:05,780 --> 00:03:08,840 It has good integration with JUnit and Mockito as well. 39 00:03:08,940 --> 00:03:17,810 Spring MVC is concerned with developing web applications. Spring MVC provides a simple way of developing 40 00:03:17,810 --> 00:03:19,700 web applications. 41 00:03:19,700 --> 00:03:26,750 One of the great thing about Spring MVC is the separation of concerns. Dispatchers servlet is concerned 42 00:03:26,750 --> 00:03:32,250 with just the basic front controller part. There is a model and view. 43 00:03:32,420 --> 00:03:39,640 There is a view resolver which is concerned just with resolving a view name to the physical view. 44 00:03:39,770 --> 00:03:46,220 With this kind of simple concepts, Spring MVC makes it very very easy to develop your web applications 45 00:03:46,820 --> 00:03:52,200 as well as your RESTful services. Whether you are developing web applications or REST services with 46 00:03:52,210 --> 00:03:53,090 Spring Boot, 47 00:03:53,100 --> 00:03:59,680 internally you are using Spring MVC framework. That's the Spring web MVC framework. 48 00:03:59,690 --> 00:04:04,820 Why do we need Spring Boot? That we have talked a lot about in this specific course. 49 00:04:04,890 --> 00:04:08,590 So in the last few steps we saw the need for Spring Boot, right? 50 00:04:08,600 --> 00:04:10,890 We don't want to be configuring things like that. 51 00:04:10,900 --> 00:04:15,230 We are configuring views resolver, we configuring dispatcher servlet. 52 00:04:15,350 --> 00:04:22,280 If we're using Hibernate JPA we need to configure datasource, entity manager and transaction manager 53 00:04:22,310 --> 00:04:24,300 and lot of that kind of stuff. 54 00:04:24,440 --> 00:04:25,840 Spring Boot says, OK! 55 00:04:25,850 --> 00:04:27,830 Why do you need to do all this configuration? 56 00:04:27,830 --> 00:04:30,000 Can we really think different? 57 00:04:30,020 --> 00:04:32,230 The thinking of Spring Boot is, OK! 58 00:04:32,450 --> 00:04:38,600 This guy has added a Spring MVC jar, so can I configure some of the beans automatically? Can I 59 00:04:38,600 --> 00:04:43,310 configure a dispatcher servlet automatically for you? Can I configure view resolver automatically 60 00:04:43,310 --> 00:04:44,140 for you? 61 00:04:44,140 --> 00:04:45,800 Can I configure a data source. 62 00:04:45,830 --> 00:04:51,520 If the hibernate jar is on the classpath. I know, he put Hibernate jar in the class because he wants 63 00:04:51,540 --> 00:04:58,350 to talk to database. Why don't I automatically create a datasource? So thats what Spring Boot does. The auto configuration 64 00:04:58,360 --> 00:05:05,240 part. It looks at frameworks which are available on the classpath and provide automatic configuration. This 65 00:05:05,240 --> 00:05:08,960 starter projects are all built around well known patterns. 66 00:05:09,030 --> 00:05:14,670 We will talk about Spring Boot starter web and Spring Boot starter JPA in the next step. 67 00:05:14,670 --> 00:05:21,730 Other than starters the important goals of Spring Boot is to provide a few monitoring features. 68 00:05:21,870 --> 00:05:27,480 So it also provides starters like Spring Boot starter actuator which is used for monitoring. 69 00:05:27,480 --> 00:05:34,510 So it enables monitoring for you application and also it has starters to pick different embedded servlet 70 00:05:34,530 --> 00:05:41,250 containers. And it has starters for logging so if you want to use log4J, there's a separate logging 71 00:05:41,250 --> 00:05:42,800 for it as well. 72 00:05:42,840 --> 00:05:50,310 I hope this video helped you to understand the difference between Spring, Spring MVC and Spring Boot. 73 00:05:50,310 --> 00:05:52,840 In the next step, we would focus on 74 00:05:53,030 --> 00:05:53,400 starters.