12th May 2026 - Syllabus Discussion Session 4

Añadido: 2026-05-26

[00:00:24]Okay.

[00:00:25]So so far we have completed three classes on syllabus discussion.

[00:00:34]And uh we have ended up discussing about a lot of important things.

[00:00:41]Let me quickly recap.

[00:00:43]So first we discussed why one has to start their learning with Core Java.

[00:00:50]Then after we discussed about what a servlet JDBC will help us to do and what's the purpose of it.

[00:01:00]Then we discussed about Spring Boot, Hibernate, Spring Security, API development, microservices Kafka, and of course about the project work I have been talking about it repeatedly that it is going to be e-commerce application that you will be developing.

[00:01:25]Now the next thing that we have then discussed about Git and GitHub.

[00:01:33]We discussed about Docker.

[00:01:35]We discussed about Jira.

[00:01:38]Why these things are necessary for a learner to learn.

[00:01:45]Okay?

[00:01:46]So what is the next thing we are going to discuss?

[00:01:50]See in today's class we are going to discuss about what is JUnit, what Mockito?

[00:01:59]And what is Jacoco?

[00:02:02]This is again very very important syllabus.

[00:02:08]When you join the company, many times in the beginning itself, they will tell you to write JUnit test cases.

[00:02:17]This will happen.

[00:02:20]So, how do we write this JUnit test case? What is JUnit? Let's understand this one by one.

[00:02:28]So, firstly, you need to understand so you have developed some code.

[00:02:34]These are all the Java code that I have already developed.

[00:02:40]Okay? This is all the Java code that I have already developed.

[00:02:46]Now, after developing this code, you're supposed to test the code.

[00:02:52]This is not the testing what your functional testers or black box testers they do.

[00:02:59]Usually what a testing team does, they'll open the login page, they'll enter username and password, click on login, login happening, the test has passed. Login not happening, application crashed, test has failed.

[00:03:15]See they're directly opening the UI.

[00:03:18]Okay? And after opening the UI, what they are doing, they're just going ahead and testing each and every feature through this user interface.

[00:03:29]They don't have any knowledge of coding.

[00:03:32]They're not performing testing on the code that is being developed.

[00:03:38]Okay? I hope you're getting this what I'm telling.

[00:03:41]Now, unit testing, when I say unit testing, or white box testing, white box testing.

[00:03:54]Now, what does this mean is you're going to now test the code that you have developed.

[00:04:02]The complete code that has been developed by you, whether that code is working properly or not, you're going to test that.

[00:04:10]Example, let's take this code is all about login.

[00:04:17]Now, when I tell you to test this, what you will do?

[00:04:20]You will provide username and password, and you will check username plus password, and you will check whether each and every line of code executing properly.

[00:04:34]If the username and password entered is valid, your code should now okay, print the status as true.

[00:04:43]Example, and in case invalid username password is given, it should print what?

[00:04:51]But, your job is to test the complete code, not the user interface.

[00:04:57]Each and every line of code, how is it working?

[00:05:00]Is my code running properly? Is there any problem at any line of Java code?

[00:05:06]Or, let's take it as an insurance calculator, life insurance.

[00:05:10]I will enter your date of birth.

[00:05:13]Right? I will enter your date of birth and other details.

[00:05:17]Now, this should calculate the yearly premium and give it to me.

[00:05:22]Correct?

[00:05:24]How your code that you have developed, right? This is all Java code that you're writing. Example, this is all Java code that you're writing.

[00:05:33]This code, is it working properly?

[00:05:37]The complete code that you have developed here, is it working properly?

[00:05:41]Testing of code that you have developed is It's as white box testing.

[00:05:46]But, how do I do this now?

[00:05:49]So, this is where the concept of JUnit the concept of JUnit then Mockito and then JaCoCo comes in picture.

[00:06:02]Now, what this does firstly when you now look at JUnit JUnit is all about testing your code.

[00:06:14]Not the UI, testing the code that you have developed.

[00:06:18]Now, in this JaCoCo is all about it will tell us how much percentage of code is being tested. Imagine I'll give valid username and password.

[00:06:28]With the valid username and password line one, line two, line three, line four got tested.

[00:06:37]These four lines got tested.

[00:06:40]However there are three lines of code that did not get tested.

[00:06:46]Let's imagine I had 10 lines of code, example.

[00:06:49]Out of which five lines got tested. So, how many lines of code did not get tested?

[00:06:57]Five.

[00:06:58]Which means 50% of my code is not being tested here.

[00:07:04]This percentage of code based on the input that you're providing how much percentage of the code is being tested not tested your JaCoCo will tell us.

[00:07:17]Right? Suppose you're testing only 50% of lines of code then your testing is incomplete.

[00:07:24]Your testing should have at least 80% coverage, which means out of 10 lines at least eight lines of your Java code should have been tested.

[00:07:36]Okay? Now, without this thing the deployment, they They not allow you to do that.

[00:07:42]If you want to deploy your code to the server, many companies will have standard benchmark that 80% of your Java code should have been tested and only after testing 80% of your Java code, you are now allowed for the deployment.

[00:08:01]The question is, how do we test how much percentage of the code has been tested, not tested?

[00:08:08]JaCoCo will give us an idea about it.

[00:08:12]Okay? Example, let me quickly take you through okay, our series of lectures that you see here.

[00:08:21]And in this not this our AI with full stack Java with AI full stack. Now, here, what I will do is I will directly take you through JUnit with Mockito.

[00:08:37]Now, here I cannot now make you understand the whole thing.

[00:08:42]Definitely, this is not possible, but I'll take you through some of the lecture that I've already taken.

[00:08:49]And a high-level understanding, you should be getting it here.

[00:08:53]Let's see this here.

[00:08:55]So, I'm opening up the screen.

[00:09:00]What happened?

[00:09:08]Okay.

[00:09:10]Some other screen is being displayed.

[00:09:18]Huh?

[00:09:21]Yeah, yeah. What?

[00:09:25]Ah, this is some other account, right?

[00:09:27]Not ours.

[00:09:33]Hold on.

[00:09:38]Ah.

[00:09:40]>> One minute, guys. Just hold on.

[00:10:07]One minute. There's some problem with the projector.

[00:10:46]Okay.

[00:10:48]Now, we are here.

[00:10:50]Observe now.

[00:10:52]Importantly, so what I'm going to do now, see there is some lecture that I've taken. I'll just show you quickly what's happening.

[00:11:00]See, firstly, there are all tests that has been written down by me.

[00:11:05]Now, this is the test, unit testing, which is going to perform testing for me by providing some inputs to the application.

[00:11:15]Right?

[00:11:16]So, I think I'll have to go to the introduction video.

[00:11:30]If I can make you see that, you might get some idea about it. Hold on.

[00:11:40]Okay.

[00:11:54]Right. So, you're writing the code here now. So, you observe what's happening.

[00:11:58]I've just executed the test.

[00:12:01]And after executing the test, you might unfortunately not Yeah, you see this here now. I got this window.

[00:12:09]So, what I did, I had a Java code, okay, called as calculator.java.

[00:12:15]Now, when I started performing testing of it, right, when I started performing testing of it, you see here the coverage.

[00:12:24]My testing has covered how many lines of Java code. Imagine I've developed 10 lines of Java code. If all 10 lines were tested by me, JaCoCo will give me a report like this, 100% coverage that has happened. There were three lines of code, right, and all the three lines of code is being tested by me. All three lines of Java code is being what? Tested by me.

[00:12:52]Now, this coverage that you see here, this coverage that you see here now, this is being given by JaCoCo.

[00:13:02]So, now imagine I have here, okay, these many lines of code, starting from line one.

[00:13:10]Let's say I've got 42 lines of code now.

[00:13:13]Now, while I'm performing testing of this code, if only 12 lines of code is being tested, okay, and rest lines of code is not being tested, that is near about 30 lines of code is not tested.

[00:13:29]Then the coverage will be calculated accordingly. That how much percentage of code has been calculated.

[00:13:36]Likewise, if I had 10 lines of code and my testing is not covering all that 10 lines. It's covering only five lines.

[00:13:45]So, percentage is 50% coverage. Did you understand this, guys?

[00:13:50]Online students, did you understand what am I talking about?

[00:13:53]Okay?

[00:13:55]Yes or no?

[00:13:58]Yes, offline students, did you understand this?

[00:14:01]Yes?

[00:14:02]Oh my god, I'll have to tell them somebody lot of people are using Wi-Fi.

[00:14:06]One minute, hold on.

[00:14:10]Hey, don't connect all the Wi-Fis. Why is so all the Wi-Fis connected? All Wi-Fis are connected.

[00:14:23]Right? So, simple thing that you need to understand how much percentage of coding is being tested.

[00:14:32]And that all depends on number of lines against total testing you have done. Hold on, let me fix this. Some problem.

[00:15:20]Okay?

[00:15:21]So, this is where we guys are going to understand about what?

[00:15:26]Your JaCoCo. So, what JUnit does? How many Okay, whatever Java code you're writing, we need to test that Java code.

[00:15:34]To test that Java code, JUnit is used.

[00:15:38]Now, with JUnit you will use JaCoCo.

[00:15:40]JaCoCo will tell the Java code that you are testing, in that how much percentage of code has been tested.

[00:15:47]And how much percentage of code you could not test.

[00:15:51]Correct? That is JaCoCo. Mockito is while we are performing testing, we will give dummy inputs.

[00:15:59]Testing is never real. Testing is all about providing dummy inputs and testing the application. So, providing of the dummy inputs to your code and to do testing, we use a concept called as Mockito.

[00:16:14]So, there are three things involved here.

[00:16:17]JUnit, Mockito, and then what?

[00:16:21]JaCoCo. Now, let me take a very simple example here.

[00:16:25]Okay?

[00:16:26]Uh JUnit, Mockito, Mockito, plus JaCoCo example with 50 percent coverage. Let's see. What do we get here? In a high-level manner, I'll just try to explain this to you now.

[00:16:48]See.

[00:16:49]What is happening now? Forget about all these code. That's not something which we are interested in.

[00:16:56]Okay.

[00:16:57]Now, what it does, see, the coverage example is total lines is 20.

[00:17:08]Okay? You have written down 20 lines of Java code.

[00:17:12]In that, you ended up testing only 12.

[00:17:16]So, what is the percentage of testing?

[00:17:19]60%.

[00:17:21]So, this says only 60% of your testing is completed.

[00:17:27]You've not done the proper testing. 60% testing is on the lower side. Minimum 80% should be the test coverage, which means 80% of 20 is how much? 16 lines. 20 into 20 into 80 divided by 100. Yes or no? So, all together it should be how many lines? 16 lines. At least 16 lines you should have tested.

[00:17:55]Bare minimum percentage I'm talking about.

[00:17:58]But you ended up doing only So, now again test in a proper way such that 80% coverage is done. Who does this?

[00:18:08]JaCoCo.

[00:18:09]Right? This is what JaCoCo does. Line coverage.

[00:18:13]Each and every line written down by you is being tested or not, it will give us the report. And JUnit is important for performing white box testing. And Mockito to provide dummy inputs. Okay. Now, let's proceed further. This is very, very important.

[00:18:32]And without this right? You cannot work in companies.

[00:18:37]Because moment anybody joins they tell them to build unit test cases.

[00:18:42]Developers will definitely get this task.

[00:18:45]Now, let's continue further.

[00:18:47]Now, we are going to talk about what is Maven.

[00:18:50]And why one has to learn Maven.

[00:18:54]See, whenever you're developing any code Okay? For this, for example, see here. I have some Java code.

[00:19:03]Now, this Java code I need to deploy that to a server.

[00:19:08]I have some Java code here.

[00:19:10]And this Java code I'm supposed to deploy that to a server.

[00:19:15]Okay, I'm supposed to deploy that to what?

[00:19:19]A server.

[00:19:20]In order to deploy this Java code on the server, or this particular Java code on the server, you cannot deploy the Java code directly.

[00:19:32]Okay, directly this code as it is you cannot deploy.

[00:19:35]The rule is you have to convert all these Java code into a machine level language.

[00:19:42]Zeros and ones.

[00:19:44]And then compress all of that into one single file, and then you deploy it.

[00:19:51]High level example. Okay, understand.

[00:19:55]There is so much of Java code written down by me.

[00:19:58]Now, you cannot deploy this Java code as it is to the server.

[00:20:04]To deploy this Java code to the server, you have to convert all of these Java code to a machine level language called as zeros and ones.

[00:20:15]And then all that zeros and ones are compressed in one single file.

[00:20:21]And that file is what you deploy to the server.

[00:20:25]So, how do I generate that particular compressed file that comprises of zeros and ones?

[00:20:33]So, one simple explanation for this is Maven. Now, you notice I have so many Java files here. Let's take the same example. I have one I have two I have three, four I have five, six seven eight nine. How many Java files have I got?

[00:20:54]Nine. Now, all of these Java code should be compiled into the machine level language, then compress that into a single file, and that file is what you will be deploying it. How to do that?

[00:21:10]So, firstly, we'll go to this path where my project is. Can you see where my project is?

[00:21:15]My project is here.

[00:21:16]If you notice, the project is in G drive, Shopify, order service.

[00:21:23]So, I'll just go to G drive.

[00:21:25]I'll just go to G drive.

[00:21:27]And here, you notice there's a folder called as Shopify.

[00:21:31]And in that, this is my project. I'll just select that.

[00:21:36]Okay? And now, I will run some Maven command. Moment I use mvn compile, which will generate a machine level code zeros and ones, and then I will do package.

[00:21:49]Moment I do that, my complete project code is compiled into your byte code, that is zeros and ones, and packaged into a single file called as a Java archive, which you will see here getting generated.

[00:22:06]So, if you now see here, after some time, you'll get a message that there is a Java archive that is being generated here.

[00:22:16]Lot of things is happening.

[00:22:18]Lot of things is happening.

[00:22:19]And now, once this is being completed, just observe here.

[00:22:27]Just observe here, one file it generated. Can you see that here?

[00:22:32]The extension of that file is JAR file.

[00:22:34]You can see it in your project as well.

[00:22:36]Now, if you go to your targets folder, you see one file got generated.

[00:22:40]This one file has complete logic that you have developed.

[00:22:46]And this file is what you will deploy to the server.

[00:22:50]Okay? Now, in order to generate this file, you require Maven.

[00:22:55]This is one of the very high level understanding of Maven. Now, in order to learn Maven, I would require at least 3 hours of class, starting from basics to advance.

[00:23:04]But for now, understand one very simple thing.

[00:23:07]Whatever project code you have, we have to take all that project code, convert to zeros and ones, compress that into a JAR file, and then we deploy to a server.

[00:23:19]How to generate that JAR file? So, this is where we use Maven, which is responsible for packaging of our application, so that we can deploy that particular application to the server.

[00:23:31]Did you understand this?

[00:23:33]Online students, did you get this, guys?

[00:23:36]Please tell me.

[00:23:39]Please tell me. Did you understand this part?

[00:23:42]Online students, Shall again I'll show you. Now, I want to deploy this notification service to server. So, first thing is I'll have to go to this project path.

[00:23:53]And in this project path, what I will do now, I'm going to Okay? Open the notification service.

[00:24:01]Forget about the commands. This all I will teach you during the class.

[00:24:05]Now, when I use this command, mvn, compile and package. Now, see. As of now, there is no JAR file that is present in here. Can you see that? Now, in this, there is nothing present. You see that? There are no JAR files present here.

[00:24:25]But now, when I hit on enter, you just see this will end up taking my complete project code. It will package that into a single file.

[00:24:35]And this JAR file is what responsible for the deployment to take place.

[00:24:42]So, actually this JAR file is then put into Docker.

[00:24:46]Okay? Now, Docker gives a platform to run this JAR file. Then it is deployed to the server.

[00:24:53]Did you Did you notice that now?

[00:24:55]Something got generated here.

[00:24:57]Something got generated here. Now, the JAR file got generated. Who is generating this JAR file?

[00:25:04]Maven.

[00:25:06]Now, without Maven, we cannot do this.

[00:25:07]Is this part clear? Are you guys not able to follow? Something if you're not able to understand, not able to follow, do let me know.

[00:25:17]Are you all clear with this part?

[00:25:19]Yes, can I assume some high-level understanding? You cannot have detailed depth learning now with 5 5 minutes of discussion what I'm doing it. This is just to give you an idea about how the topic selection is done for your training.

[00:25:36]Of course, you cannot have a depth idea and like, you know, start feeling that, "Okay, you know what? In 5 minutes sir will make me understand everything in depth manner."

[00:25:43]That's not possible.

[00:25:45]High-level understanding is what you will develop as of now. Okay.

[00:25:50]Now, the next thing what we guys are going to look at, see here. We have just talked about now.

[00:25:57]Okay, JUnit, Mockito, JaCoCo. We talked about Maven.

[00:26:01]Now, we are going to talk about what is this Jenkins all about.

[00:26:06]Why Jenkins is required. What is the purpose of Jenkins?

[00:26:11]See, in the companies the complete deployment of your project will be automated.

[00:26:18]You will never manually deploy your project to server.

[00:26:22]So, what happens is these developers these developers have developed the code. And after developing the code, you know this very well.

[00:26:35]You know this very well. This code will be put into GitHub.

[00:26:40]I've already talked about it earlier.

[00:26:42]Yes or no?

[00:26:43]This code will be put into GitHub.

[00:26:46]Now, moment this code is put into GitHub what will happen?

[00:26:51]This GitHub moment it receives the code, there's something called as Jenkins.

[00:26:58]Now, this Jenkins is an automation server.

[00:27:01]So, what it does, it keeps checking GitHub.

[00:27:05]Moment it sees that there is a new code put into GitHub, Jenkins will pick up that code.

[00:27:12]And after picking that Java code, because what you're putting into GitHub is a purely Java code.

[00:27:18]Now, Jenkins will automatically pick that Java code from your GitHub, and that Java code Jenkins will give it to Maven.

[00:27:28]Tell me why we should use Maven here now.

[00:27:31]Because Maven is the one that will take that Java code, and it will produce one JAR file.

[00:27:39]Will produce one JAR file. Now, this JAR file has your bytecode. Bytecode is zeros and ones which your machine can understand.

[00:27:49]Find everybody able to understand this?

[00:27:52]Okay, so automatically Jenkins is doing this. It automatically takes your project code from GitHub, Jenkins automatically gives it to Maven. Maven produces a JAR file.

[00:28:04]Now, this JAR file then Jenkins takes that JAR file, and automatically it gives this to Docker. It will automatically give it to what?

[00:28:14]Docker. This all been created.

[00:28:17]All these setup has been already done.

[00:28:20]Okay, by the DevOps team.

[00:28:23]Okay, DevOps engineer. So, what he will do, he will set up Jenkins, Maven, Docker. So, automatically Jenkins is going to read your Java code. It will give it to Maven. Maven will produce a JAR file. That JAR file is given to Docker. Now, Docker will take that JAR file, and further it will provide an environment to run the JAR file. To run this JAR file, Docker provides an environment so that it becomes a platform independent environment to run on any server.

[00:28:58]Okay? So, here your Docker is now going to take this JAR file and that JAR file, it will put that into something called as a Docker image.

[00:29:11]Now, this Docker image is the one which knows the JAR file to run. And to run this JAR file, which version of Java is required, what all softwares are required, already configured.

[00:29:25]And this Docker image is something platform independent and ready to run on any server.

[00:29:33]Are you understanding, guys?

[00:29:35]Yes?

[00:29:37]Okay?

[00:29:38]So, further, we will also understand Kubernetes. What is Kubernetes and why we should learn that.

[00:29:46]But, please look at here now.

[00:29:48]This whole thing is being automated by Jenkins.

[00:29:53]When the developer puts the code to GitHub, Jenkins automatically picks that code.

[00:29:58]That code Jenkins will automatically give it to Maven. Maven will generate that JAR file. That JAR file is given to Docker. Docker takes the JAR file, creates a Docker image. Now, this Docker image is ready to run on any server because Docker image is platform independent.

[00:30:15]So, whether it is Linux, Windows, whichever server it is, it will run.

[00:30:20]But, this whole process is automated now. Tomorrow, if the developer adds some new feature and that new features are added to GitHub, moment you add the new features to GitHub, Jenkins will automatically pick up, give it to Maven.

[00:30:33]Maven produces a JAR file. JAR file is a byte code. That byte code is given to Docker. Docker takes that particular byte code, produces a Docker image.

[00:30:43]Docker image is a combination of your JAR file plus the required environment to run that.

[00:30:51]Okay? That is JDK, which version is required, MySQL database, XYZ, everything your Docker is going to take care of it. And that will now run on any servers.

[00:31:03]Okay? Is this part clear? Students, online students, offline students, did you understand this? Please tell me.

[00:31:11]Online and offline students, did you understand this? Please tell me.

[00:31:16]Yes?

[00:31:18]Everyone, so you will you will just get this idea in a high-level manner.

[00:31:24]Again, I'm telling you because we're just discussing about the syllabus, decoding it in a very very high-level manner. To learn this in-depth manner, okay? It will take time. Sir, after taking JAR byte code, again Jenkins will give it to Docker, right, sir? Yes.

[00:31:42]Okay? So, this is the first step Jenkins will do. Second step, this. Third step, this. Okay? This whole thing is now called as a CI/CD pipeline.

[00:31:54]Okay? CI/CD pipeline. So, for that we have separate section of notes that has been given here. If you just go here, observe. When you now search for search for Jenkins, you will find complete notes given by me.

[00:32:13]Okay? Jenkins.

[00:32:17]Right?

[00:32:19]So, this complete notes that has been given here. Okay, what Jenkins does, what is continuous integration and continuous deployment.

[00:32:28]So, continuously developers writing the code to GitHub, Jenkins automatically picks that, and the new code is deployed to the server. This complete process will be automated.

[00:32:38]You will not do this manually. It is once once once you do this setup, the deployment is automated. And this whole process is called as CI/CD pipeline.

[00:32:49]What is it called as?

[00:32:51]CI/CD pipeline. Is this clear?

[00:32:55]Everyone?

[00:32:57]So, we have a lot of other things like we have Kubernetes.

[00:33:01]We'll discuss about that what Kubernetes is.

[00:33:04]Let me wrap that up today itself. So, tomorrow onwards we can start with actual core Java programming.

[00:33:11]Okay?

[00:33:16]See, what happens is today you cannot segregate your work telling that the developer will only do this. I will not do that. See, today because of AI, the expectations of the employees okay, to know these technologies okay, is a mandatory stuff.

[00:33:35]Because some clients you might get in a project they might use you as a back-end developer.

[00:33:41]But once that project gets over, they want to move you to DevOps, you should be ready to go for it.

[00:33:46]Otherwise, sustaining in the company today's market, this is going to be very very difficult.

[00:33:54]Right? You just have, you know, a very basic knowledge, basic information, and you expect that you guys are going to now sustain in the market, then this will not happen.

[00:34:07]Please understand that.

[00:34:09]Okay? So, everything has to be a depth learning. You compromise with your learning, you learn basic things, and you tell I want a job. Forget about getting a job, you will not get through.

[00:34:21]Okay? You will just not get through. So, keep this in mind.

[00:34:25]Okay? Whatever now it is sounding, okay, so this much all we have to study, it looks complex, but yes, this is the reality.

[00:34:34]Okay?

[00:34:35]So, let's now look at what is Kubernetes.

[00:34:38]See, Kubernetes is again a very beautiful stuff initially created by Google.

[00:34:47]So, this is also called as K 8 S.

[00:34:51]So, between your Kubernetes word, there are eight characters.

[00:34:55]So, in shortcut, it is called as K8S.

[00:34:58]Now, what this Kubernetes does, see, whenever you deploy your application, there are few things you have to take care of, like auto scaling.

[00:35:08]Auto scaling.

[00:35:11]Now, what is this auto scaling?

[00:35:13]So, let's assume today, your application, you're running it in server one.

[00:35:21]This is where your application you're running, server one.

[00:35:25]Now, when you're running your application in server one, understand here, okay?

[00:35:32]As of today, the number of users accessing this is 5,000.

[00:35:38]But now, all of a sudden, this e-commerce application, they started running some advertisements and some sale, like 50% discount.

[00:35:49]Okay? 70% discount, 50% discount.

[00:35:52]The load all of a sudden increased now from okay, 5,000 to let's say, okay, 5 lakh users every hour.

[00:36:05]Okay? 5 lakh users every hour.

[00:36:09]Now, one server cannot withstand this whole load now.

[00:36:14]As long as it was 5,000 users, the server performance was good.

[00:36:18]But moment the server load increased to 5 lakhs, understand this here now, okay, your server is going to definitely crash.

[00:36:28]Example, if you just look at Okay, you know, per minute traffic per 1 minute traffic on Amazon.

[00:36:40]Now, just look at what it claims. How much traffic they're getting every 1 minute?

[00:36:45]The estimated traffic website visitors Okay, approximately 2 to 4 millions.

[00:36:54]Right? So, millions of users browse the product, thousands of place order, approximately every minute, they have 10,000 to 18,000 orders being placed.

[00:37:07]How much?

[00:37:09]10,000 to 18,000 orders are being placed. Now, understand.

[00:37:14]This is the normal scenario.

[00:37:16]But, there's a peak sale.

[00:37:18]Much higher. Now, when you have this Black Friday uh uh you know, some other sales is going on, Diwali sale, or something like that, this visitors will grow three times.

[00:37:30]Now, the question is how do I handle this traffic?

[00:37:35]Right? How do I handle this traffic?

[00:37:37]So, this is where auto scaling comes in picture.

[00:37:41]So, what this auto scaling does it provides a very beautiful feature.

[00:37:46]Suppose today, there is only one, you know, server because the load is 5,000.

[00:37:52]Suddenly, when the load increases to 50,000 the number of servers will automatically increase to two.

[00:37:59]Which means same application now will end up running on two because the load increased.

[00:38:05]The number of servers will automatically increase and decrease depending on the load.

[00:38:10]Imagine the number of users now increased to 1 lakh. One more One more server got added.

[00:38:16]The load increased to 3 lakhs. One more server got added.

[00:38:20]This is auto scaling where your application was running on one server, when the traffic when the incoming traffic is increasing, automatically the number of servers are increasing.

[00:38:32]And then, you notice that the load is decreasing, the servers are automatically now reducing.

[00:38:41]Which means, you notice increasing of servers and decreasing of servers is now happening automatically depending on the incoming traffic.

[00:38:55]Correct?

[00:38:56]Now, this beautiful concept is basically called as auto-scaling when it Okay, basically comes in DevOps. Did you understand this now? What is auto-scaling? Tell me.

[00:39:08]What is auto-scaling? Repeat.

[00:39:10]What is auto-scaling?

[00:39:12]The number of servers will automatically increase and decrease depending on the traffic.

[00:39:19]Now, there's one more thing that might happen here.

[00:39:22]Now, let's assume as of now, I've got three servers.

[00:39:27]As of now, I've got three servers.

[00:39:30]Now, many times it might happen, for some reason, one of the server crashed.

[00:39:36]Now, when one of the server goes down, we should have a concept called as disaster recovery.

[00:39:44]Disaster recovery.

[00:39:48]What is the concept we should have?

[00:39:50]Disaster recovery. So, disaster recovery is a concept where if one of the server goes down, automatically that will be replaced with a new server.

[00:40:03]That will be automatically replaced with what?

[00:40:06]A new server.

[00:40:08]Moment one server goes down, that server is replaced with a fresh new server.

[00:40:15]Correct? This is called as a disaster recovery. When something goes wrong, how will you tackle that situation?

[00:40:21]Now, these all beautiful concepts that we are talking about, your Kubernetes takes care of it.

[00:40:30]Which means if you don't know Kubernetes, you will not be able to implement this effectively.

[00:40:36]Not only that, there's one more thing that might happen called as load balancing.

[00:40:42]Now, what is a load balancing?

[00:40:44]Imagine my application is running on three servers.

[00:40:49]Now, load balancing is a concept where whatever incoming traffic is coming to your servers, whatever incoming traffic is coming to your application, automatically this load is split on the multiple servers.

[00:41:05]The first incoming request will go to first server, second request to second server, the third request will go to third server, then the next request again to first server.

[00:41:16]The next request second server, the load is getting split on multiple servers where your same application is running.

[00:41:26]Which balances your load.

[00:41:29]Rather than putting one load on complete one server, this load can be balanced, which is called as load balancing. What is it called as?

[00:41:39]Load balancer.

[00:41:42]This all concepts, if you want during your deployment, we have to use what?

[00:41:49]Kubernetes. And that is what you guys are seeing here.

[00:41:53]Okay? That you guys are learning what?

[00:41:56]Kubernetes in detailed manner. Did you understand this, guys? Yeah? So, it is not just going out and creating one server setup and your job is done.

[00:42:05]Please understand, whenever you people are deploying your application, there are a lot of things you have to take care of. Because imagine applications like Amazon, you notice here in applications like Amazon, what we see here is basically every, you know, hour, just in India, every 1 hour there are 5 lakh orders that is being placed.

[00:42:29]Which means, observe, in, you know, every 1 hour they claim approximately 5 lakh orders are placed.

[00:42:38]And there are millions and millions of users using the application every 1 minute.

[00:42:43]That is the kind of traffic it has.

[00:42:45]Now, if you do not, you know, provide a proper setup to run that application, your application will crash, the application performance will not be good. These are all challenges you will start seeing here.

[00:42:59]So, this is where, right, we people will learn Kubernetes.

[00:43:05]So, we have separate lectures. Again, if you see here, I have complete detailed lectures on Kubernetes that's been taken here under tools training.

[00:43:18]Right? We have Kubernetes. Almost nine sessions I've taken on that.

[00:43:25]Okay? Nine sessions I've taken on that.

[00:43:28]So, this will take care of deploying your application with importantly three things.

[00:43:34]Load balancing, disaster recovery, one server crashes, it replaces that with the new one, disaster recovery, and then we have auto scaling. The number of servers can increase and decrease.

[00:43:49]Right? Depending on the load. And then load balancing. Every server should get the incoming request load distributed.

[00:43:58]So, that you don't put the complete load on one server only. And with all of these knowledge, definitely yes, very important thing is we have to work on the project. So, this is where the complete project where I've taken near about 28 session.

[00:44:17]There are 28 lectures taken on project alone.

[00:44:22]Starting from the basic thing till your design pattern.

[00:44:27]Like the design pattern will tell imagine you did a transaction.

[00:44:31]Right? Now, if the transaction passed, what will you do? Payment passed, what will you do? When the payment failed, what will you do?

[00:44:38]This all we guys are going to learn here.

[00:44:42]So, this is all about your road map, guys.

[00:44:46]Okay? This is all about your road map which will consist of 255 lectures.

[00:44:52]Approx, you can consider somewhere around 200 hours of syllabus, which is really huge.

[00:45:00]Now, once this has been completed, you're well prepared, practiced well, resume preparation will happen, and placements will begin.

[00:45:09]Now, from tomorrow's class, actual syllabus will begin, which is a must.

[00:45:15]Okay?

[00:45:16]Because you miss tomorrow's class, then day after tomorrow onwards, you will not be able to follow me.

[00:45:25]If you want to follow my classes now, very properly step by step, then the actual programming classes will begin from tomorrow. As per our road map, I'm going to start off with core Java classes starting from tomorrow.

[00:45:41]Okay? So, tomorrow's class you miss and you come day after tomorrow, that's it.

[00:45:45]You'll not be able to follow me then.

[00:45:48]Okay? I hope this part is clear for all of you.

[00:45:52]Sure? Everyone? So, now you can start analyzing from tomorrow the way we are training, the way we are teaching you, is it easy? You're able to follow, not able to follow, what's happening? You can start analyzing that.

[00:46:08]And accordingly, you can keep taking up the decision. As and when people are joining the program, I'll keep giving them the access to this recorded classes.

[00:46:17]Right? And one who feels, "Okay, you know what? I'm quite intelligent enough.

[00:46:21]I'll start off with the recorded classes, try to finish the lectures quickly, and try to get a job." Then complete lectures, I'll be providing it to you. You can go ahead of me as well.

[00:46:31]Right? You can you know, you can learn via only live classes, or you can learn the recorded classes, and sit in live class, and again take that as a revision.

[00:46:43]Right? You can consider that as what?

[00:46:45]Revision. So, in app, it's showing that you're not adding to any batch. No, I will add. I think one has already made the payment. I think two people have already made the payment.

[00:46:55]And one who has done the payment, don't worry about that.

[00:46:59]I will start adding you to the batch.

[00:47:02]So, please share your details today.

[00:47:04]I've received some information.

[00:47:06]Okay? So, the payment wise, see, this is the number.

[00:47:12]Just WhatsApp this number.

[00:47:14]Right? And they will guide you for the payment. Moment the payment is done, you will get an access to this complete recorded classes of previous batch.

[00:47:27]And that is all being kept in sequence.

[00:47:30]You would just follow the sequence.

[00:47:32]Like this. This already I've covered.

[00:47:34]So, you can skip this.

[00:47:36]So, sequence will start from core Java, SQL, JSP, Hibernate, Spring Boot, Spring Security. So, this is the complete sequence you will be following.

[00:47:46]As it is.

[00:47:48]Okay? That's a complete as per our road map, how you are to learn, that has been put here. This is the contact number.

[00:47:54]Any other questions do you have it?

[00:47:58]Any other questions do you have it?

[00:48:01]Before we start with core Java classes from tomorrow.

[00:48:07]Huh?

[00:48:10]Tell me.

[00:48:15]Huh?

[00:48:19]Huh?

[00:48:21]Yes.

[00:48:25]Already have discussed about that. See, we are first taking foundation of microservices and the whole project itself is microservices.

[00:48:33]Because without micro see now when we are using Kafka you understand if you notice our recordings when you're using Kafka right? When you're using Kafka here we started with Kafka the latest version.

[00:48:52]If you're using Kafka means it is microservices project only.

[00:48:56]Okay? Otherwise you cannot use Kafka. I have paid the fees. Okay, you will get it. You will get it. Okay?

[00:49:03]So whoever has made the payment do not worry.

[00:49:08]I'm going to now update the Excel and I will start okay adding you to the batch.

[00:49:15]Fine. We will do that. Nothing to worry.

[00:49:17]See, I'm not going to take probably I might give you some five classes on core Java and then we're going to start off with the paid batch.

[00:49:26]Okay, that is what it is going to be.

[00:49:28]So don't expect 1 1 month I'm going to give you a trial.

[00:49:33]Right? So it will be like strictly 10 classes I'll be giving you. You can take a call. You like it, you can continue.

[00:49:40]You don't like it, you can drop.

[00:49:42]Okay? Actual classes will start from tomorrow and I'll add you to this batch because my whole concern is along with this the recorded classes has to go parallelly along with my live classes.

[00:49:54]Okay.

[00:49:56]Yeah, you can do it. No problem. Sir, can I start with advanced part because I know Java? Yes, Shubham, you can do that.

[00:50:02]If you already know that, see, suppose you already know core Java, just see the syllabus that is not covered.

[00:50:09]Suppose, uh you know, some data structures part was missed during your learning that you see here.

[00:50:18]Right? Then, in that case, you at least pick those lectures which you skipped it in your Java, but you feel I know all of these data structures also, your stream API also, everything.

[00:50:31]I know SQL also, JSP is also. Then, directly you can start with Hibernate.

[00:50:34]So, probably you can connect with me later, and I will guide you. I'll understand what all things you know, and accordingly I will guide you.

[00:50:42]Sir, uh basic system is enough, guys.

[00:50:46]512 SSD is more than enough. See, I myself the system that I'm using it, I've I've kept on upgrading it. This is almost somewhere around 10 years old system.

[00:50:58]This is not something which I took it now. I think I purchased this in 2011.

[00:51:03]But, I've been upgrading it. So, if you notice, uh you know, I upgraded the See, 8 GB RAM that was installed, and then after that, uh you know, 500 GB SSD, and then after that, I just replaced this with a touch screen, the monitor.

[00:51:22]So, I just kept on upgrading it.

[00:51:24]If you have old laptops, right? Do not invest money, okay? Again, on a new laptop and burden your parents.

[00:51:33]Be smart.

[00:51:35]If you have that funds to take it, no issues with that.

[00:51:39]But, suppose you don't have funds, then don't unnecessarily take a loan EMI and burden your parents to purchase a new laptop again for you.

[00:51:47]So, see what you can do is if you have old laptops, suppose you're in Bangalore or every city, there will be one market for digital things. Like in Bangalore, it is SP Road.

[00:52:01]So, this is a digital market hub in Bangalore.

[00:52:04]You just take your laptop here.

[00:52:07]And what do you do is you tell them I want to upgrade my laptop Kingston.

[00:52:12]Okay? You know, 500 GB SSD.

[00:52:16]Upgrade RAM if possible to 8GB. Might cost you 3,000 500. And they will install operating system and give it to you.

[00:52:24]Right?

[00:52:25]So, this is one thing. Second, sir, you're in your own city, upgrade that.

[00:52:31]Sir, I don't have laptop at all.

[00:52:34]Then, the same market, they have second hand laptops.

[00:52:38]Now, they give you 1-month warranty and they're trustworthy.

[00:52:42]They have the shops there. They're trustworthy. You can do a research, go there. 12,000 to 15,000 you will get a laptop. You can purchase it. Don't invest 30 and 40,000 rupees on the laptops because for us, see, we don't require graphics card and all of these things.

[00:52:59]Java will start from very basics.

[00:53:02]I'm going to start from the very basic level keeping in mind that you don't know anything about coding. And from tomorrow's class, this will get very interesting.

[00:53:10]Because the actual learning and understanding will begin.

[00:53:14]Okay? So, we'll keep that in mind.

[00:53:16]Any other questions, students?

[00:53:22]No.

[00:53:23]See, our app access where you will get, this is the URL, learning learning {dot} pankajsiracademy.com.

[00:53:33]Okay? This is what you will be doing it.

[00:53:35]Fine? So, all my live classes you will see here on the homepage. So, once we give you an access, you can log in and access this particular website. Like these are all the current classes going on right of mine.

[00:53:47]So, this is the recorded one.

[00:53:52]The full stack with Java. Okay? So, this is the recorded one.

[00:53:55]Which will give you an access from the back end. And here I'm going to add a new batch today.

[00:54:01]Which is going to be called as 12th May batch.

[00:54:06]And we will keep getting you access in that. Access in both you will be getting But these are system protected. Every system there is a unique key generated.

[00:54:16]Any multi-device login happens, the account will get suspended.

[00:54:21]Please keep this in mind. It is one system throughout the course. Suppose you're changing your system, inform us.

[00:54:28]Because during the audit definitely we will be able to understand that how many active devices is accessing the application on.

[00:54:36]There are a lot of active devices you're using it, account will get suspended.

[00:54:40]Please don't do that.

[00:54:42]Okay?

[00:54:43]Right.

[00:54:44]So, any other doubts do you have it apart from that for me? Do you want to discuss anything with me? Live classes only available on mobile or laptop? It's available on laptops.

[00:54:56]Earlier we were keeping it only on mobile.

[00:54:59]But now many students started requesting there will be a better clarity when the classes are being taken in laptops. We get a bigger screen. So, we don't strain our eyes more.

[00:55:10]Right? So, we decided to change the software.

[00:55:13]So, earlier we were using some other application for online classes.

[00:55:17]Then we started evaluating it. We came across one of the application which even your PW is using.

[00:55:25]The same application that we're using it, it's the same application, same vendor, same company. They have also basically taken it on the subscription basis. And I found this to be really good. So, uh this is month only actually we have changed the software. So, now everybody gets a desktop access. Okay?

[00:55:44]Browser-based access. Anything else?

[00:55:49]Anything else?

[00:55:51]Sir, can we switch from online to offline classes? Yeah. See, but trust me, there will not be any difference online or offline. It will be the same.

[00:56:02]It's only the mind.

[00:56:04]Okay?

[00:56:05]You should be focused. That's it.

[00:56:07]You sit in front of laptop or in front of me. If you're not focused, then ultimately you will not learn anything.

[00:56:14]Major thing is stay focused.

[00:56:17]Okay? That's very important. Okay? Doubt clearing, whether online or offline, we'll definitely work on that. And if anybody has any doubt going forward, you can raise your hand and I will unmute you here. You can ask me questions directly. In case during the class, you've not understood something.

[00:56:36]So, tomorrow's class, important one. Tomorrow's class, very crucial one.

[00:56:45]Because programming classes will begin.

[00:56:48]You miss the syllabus class, half of the things you understood here and there, that's okay. You can still look at the recorded classes and understand the things nicely.

[00:56:56]But tomorrow's class, when you miss it, then making a comeback is difficult.

[00:57:03]Right? You miss one class, then you have a backlog because it's a continuation now, like your web series.

[00:57:10]When you watch any web series in Netflix, you watch the first video?

[00:57:15]No, you directly start off with episode five, you'll not even know what's happening.

[00:57:19]The same thing is going to happen here, so please be very careful about it.

[00:57:23]Strictly attendance will be taken online and offline both.

[00:57:27]So, we get the attendance report that what's happening with the students.

[00:57:34]Anything else? Any other doubts, questions?

[00:57:44]See, the thing is suppose a student is not placed, definitely we will extend the access for them for revision preparation purpose because even we want the students to get a job.

[00:57:57]The whole No, no, no. See, it's not like this.

[00:58:05]What happens is once you're inside the company then students come back to me and ask me only a particular part of the course access.

[00:58:14]They don't ask me core Java.

[00:58:17]They might ask that, "Okay, you know, we are working on DevOps and can you just get me the access because they want to revise once again."

[00:58:23]That support will be there. A part of the course that you select to be given.

[00:58:28]The complete course access will not be given again.

[00:58:31]See, let me not commit anything wrong.

[00:58:33]Because tomorrow then you will come and tell that, "Sir, you already told us this."

[00:58:37]Okay? The reason why we don't do that is because you got placed then, you know, you try to help your juniors.

[00:58:44]Right? So, that is the reason like, you know, the system is fixed.

[00:58:48]Okay?

[00:58:49]A part of the course access will be given provided you require that.

[00:58:54]Any other question?

[00:58:57]That's it?

[00:58:58]All understood the road map clearly, you know?

[00:59:01]Yes? Did you get some confidence?

[00:59:05]What are we going to learn? What you are going to actually go through, you know, your training? Some confidence did you get? Or you're not at all confident?

[00:59:16]Huh?

[00:59:18]Little bit online students?

[00:59:20]Did you get some confidence?

[00:59:23]Or no confidence?

[00:59:27]Confident at least basic understanding of the road map.

[00:59:31]It's like more like counseling what I did right now.

[00:59:34]What I did is right now only counseling.

[00:59:36]You cannot have 100% understanding.

[00:59:38]But at least we know, okay, you know, these are the technologies that is present.

[00:59:43]That one has to learn to get a job.

[00:59:45]However, not 100% understanding.

[00:59:49]Yeah?

[00:59:50]That's it then. I'm going to stop here my base session here.

[00:59:54]Sir, it will end in how many months, sir?

[00:59:57]With a seat.

[00:59:59]How many months it will end in the sense my live class? I've already told you. It might take six and seven months. Six and a half to seven months.

[01:00:07]You want to finish quickly?

[01:00:09]Parallelly start with the recorded series, finish and sit for placements.

[01:00:12]I'm not stopping you.

[01:00:13]You can finish in three and a half months, do it.

[01:00:17]I've given you access for complete lecture.

[01:00:19]It's your potential.

[01:00:21]Now one who feels I'll go slowly with sir's live class go with live classes.

[01:00:26]Live classes will take time.

[01:00:28]Recorded classes you can adjust at your own speed.

[01:00:32]You can take two to lectures one day.

[01:00:35]Yes, you can do that.

[01:00:37]Anushka, the payment tomorrow, no problem. Sir, I watch in new YouTube DevOps now need Hey, that is only 13 classes, baba.

[01:00:45]See, understand Ashutosh.

[01:00:49]See, what you've seen the YouTube, I'll show you what is DevOps lecture here.

[01:00:55]See, DevOps has these many sections.

[01:00:57]Don't get confused.

[01:01:01]Okay?

[01:01:02]Now starting from here is DevOps Linux shell scripting. In YouTube only learning Linux is there, 14 lectures.

[01:01:10]Now after that, you need to learn shell scripting, AWS services, tools training, and JUnit.

[01:01:19]Now these things is what you need to learn. Linux shell scripting AWS tool.

[01:01:24]Once you finish this, then you know DevOps.

[01:01:29]So, what is there on YouTube is only this.

[01:01:32]14 lessons of Linux.

[01:01:34]Just as a demo we have kept it there.

[01:01:36]Okay?

[01:01:38]Right.

[01:01:39]Suppose a person does not get placed in the course to we will extend the course duration without any charges.

[01:01:45]Firstly, Ankita.

[01:01:47]Second thing is See, it might happen some people might take more time to learn.

[01:01:55]The slow learners. Then extensions will be provided.

[01:01:58]Like my morning batch, September batch also I'm giving them extensions.

[01:02:02]I'm giving them additional two, three months more for the preparation to be done. See, that cooperation will be there on mutual understanding. Don't worry about that.

[01:02:11]Okay?

[01:02:16]Fine?

[01:02:19]Tomorrow onwards no questions taking. It will be only technical on