OOP 1 | Introduction & Concepts - Classes, Objects, Constructors, Keywords

The first video of the complete object oriented programming (#OOP) course in Java. Covering an introduction, important concepts about classes, objects, constructors, memory management, keywords, wrapper classes, and more.
Complete OOP playlist: • Object Oriented Progra...
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👉 Resources
- Join Replit: join.replit.com/kunal-kushwaha
- Complete Java DSA playlist: • Java + DSA + Interview...
- Code, Assignments, & Notes: github.com/kunal-kushwaha/DSA...
➡️ Connect with me: www.techwithkunal.com
=========================================
Timestamps:
0:00:00 Teaser
0:00:30 Introduction
0:01:53 Notes
0:03:08 OOP Introduction
0:07:45 Java Classes
0:10:35 Example of a Class
0:15:47 Java Objects
0:17:05 Class vs Object
0:18:18 Properties of Object
0:20:29 Objects Introduction
0:23:55 How to access instance variables?
0:27:35 How to create objects?
0:34:09 Dynamic Memory Allocation
0:38:24 How to manipulate objects?
0:42:20 Java Constructors
0:49:53 By Default Constructor
0:53:26 Creating Constructors
0:56:20 "this" keyword
1:09:04 Constructor Overloading
1:15:18 Calling a constructor from another constructor
1:18:31 Why we don't use "new" keyword for creating primitive data types?
1:20:35 Memory Allocation of "new" keyword
1:23:36 Wrapper Classes
1:28:07 "final" keyword
1:34:36 Garbage Collection
1:41:07 Outro
#placement #dsa #interviews

[@pranayyadav7712]

Believe me when I say, there is no course Paid/free that competes with this playlist. I've watched 15+ courses on Java both paid and free but no course stands a chance. Thanks a lot brother !

[@KunalKushwaha]

Thank You!

[@sarthakkhutafale350]

Thats true

[@nightangel6009]

@@KunalKushwaha C# aslo same course ???

[@Abhigyan103]

No doubt his teaching skills are next level.. but bro.. Sirf tutorials hi dekhte rahoge kya ?

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yes actually thats true but tu thoda jada hi makkhan mar raha he

[@snow__den]

Bro trust me i have never seen a young teacher like you, just amazing. Keep up the good work

[@KunalKushwaha]

Happy to help

[@vishalgupta7522]

Can i start this if i dont know p about programming will just start my btech ?????

[@pranavajay5528]

@@vishalgupta7522 Yeah

[@PradeepYadav-fg2yg]

1:27:42 standing by his words when he says he'll teach you everything, literally teaching everything fan moment for me🙏🙏

[@YogaNarasimhaEpuri]

Hello, can you explain why the values are not changed, since wrapper classes are non-primitive, so the during passing wrapper Objects as an parameters, reference value is shared, both objects are pointing to the same object in heap, since non-primitive value can be changed.. So, why values in outside of the function is not changed?? Thanks in advance ....🙂

[@lohithgongada9012]

@@YogaNarasimhaEpuri 1.Because the wrapper calsses are declared as final in Java 2.Assigning a new value to a wrapper class creates a new object with that value, but the original object remains unchanged. The point is "Immutability of Wrapper Classes"

[@codewithbishal895]

please​@@YogaNarasimhaEpuri

[@trushilp9]

the way you trigger the doubts which an average learner can have is literally amazing thing..

[@Sakshi01188]

can you tell me where is the link of notes.

[@mdkasif6100]

Can't thank you enough. You're even making videos on diwali for us. I assure you when I(many of us) reach a certain position in my(our) lives , we will certainly follow your footsteps and do something for the community.

[@KunalKushwaha]

It's my pleasure

[@prakharsrivastava3799]

Pre recorded rehta h bhai 😂 Phir bhi thanks Kunal 😀

[@vishalgupta7522]

Can i start this if i dont know p about programming will just start my btech ?????

[@kiku_to_herself]

@@vishalgupta7522 yes , its great

[@sabrinanastasi5809]

I completely agree with you!

[@ayushmansrivastav6898]

Now it feel like " Yhi h OOPs ?? Isi ke liye itta preshan tha 🥺" . Amazing ♥️

[@KunalKushwaha]

aage aage dekho hota hai kya

[@ayushmansrivastav6898]

Thanku brother

[@sanskarbomble7554]

Lol 🤣

[@lorraineipambonj8785]

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[@hegde421201]

The young man needs to be praised for giving his best to teach young people like him and increase programming "Consciousness".

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You explained a lot more, a lot more comprehensively than my lecturer did during 4 lectures.

[@Selim_Hasan_Raj]

This guy is making the world a better place

[@sanskarbomble7554]

Lol 🤣

[@mohammadthousif7439]

No one ever explained what classes and objects are like this guy did !! Bestest course for understanding OOPS concepts and Java . Keep doing great stuff 👍.

[@aashutoshkumar5672]

Timestamps: 0:00:00 Teaser 0:00:30 Introduction 0:01:53 Notes 0:03:08 OOP Introduction 0:07:45 Java Classes 0:10:35 Example of a Class 0:15:47 Java Objects 0:17:05 Class vs Object 0:18:18 Properties of Object 0:20:29 Objects Introduction 0:23:55 How to access instance variables? 0:27:35 How to create objects? 0:34:09 Dynamic Memory Allocation 0:38:24 How to manipulate objects? 0:42:20 Java Constructors 0:49:53 By Default Constructor 0:53:26 Creating Constructors 0:56:20 "this" keyword 1:09:04 Constructor Overloading 1:15:18 Calling a constructor from another constructor 1:18:31 Why we don't use "new" keyword for creating primitive data types? 1:20:35 Memory Allocation of "new" keyword 1:23:36 Wrapper Classes 1:28:07 "final" keyword 1:34:36 Garbage Collection 1:41:07 Outro

[@trueemperor3647]

Need these legends everywhere to save time

[@ahmadbahal5622]

Can you help me out where the notes is actually ?

[@bhushanthombare-ng9vr]

@@RVhr_1 where is the notes guys?

[@piyushbhardwajknowledgeent3444]

Thank you😅 you really save my time a lot

[@vaibhavchougule-vs6fs]

Believe me , I am absent in every lecture of my collage but I am regularly present here for learning java from you because you having the best teaching style .. and I like it .. thank you so much for these amazing playlist..❤❤😍😍

[@KaisarAnvar]

I'm so happy I discovered you. I've been to several interviews and I am familiar with quite a majority of these topics but, man..... right at the beginning, you surprised me with such a direct, straight-to-the-point, humble, yet precise approach to explaining the first topic. This means that the rest of the lecture will be just as brilliant as the beginning. I remember reading a quote that says "If the tip of the waterwall is clean, the rest of the water is clean". Heard of this somewhere but I don't remember where 😇 thanks again, and looking forward to the journey to brush up on my weaknesses now.

[@jungerpl5261]

Yo, this is the best Java tutorial you can find. I've watched whole during one weekend cuz i had an interview task to do. After this course i've done everything i was asked for. Props to this guy.

[@KunalKushwaha]

thank you

[@mkhadka123]

Same here, also thinking of learning from this series during the weekend for an interview in the coming week.

[@GauravChauhan-nu5fc]

​@@mkhadka123can we start learning directing from oops in Java??

[@samanvithac7397]

@@GauravChauhan-nu5fc nope

[@tirakv]

Just passed through the first lesson and i'm so flabbergasted that this is a free tutorial. Cheers man. You're a great teacher!

[@KunalKushwaha]

Awesome, thank you!

[@kreynusr4242]

Kunal, you have the best courses across youtube, hell across the internet, that I have ever seen. You explain everything in detail but do not overwhelm us. Props to you. Even though I'm taking a bootcamp to become a full stack developer, I always come to your videos to fully understand something.

[@RahulKumar-oi5pp]

What a course, kunal. Amazing work bro ♥️ I would just love to see other courses as well like this DSA Bootcamp. Keep Going bro. Lots of love 💚

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This playlist is even helpful for the people who already know all this. This video has cleared so many of my doubts. 👍👍

[@charanmc4484]

I recommended this channel to 5 of my friends who asked for Java preparation...and they all thanked me for such a blasting suggestion... they liked it very much...👌 Thanks Kunal for providing us quality content for no cost to everyone. It's a boon for the ppl who can't afford to buy any courses... Will always be thankful for this..💫

[@KrishNamaste]

At 48:00, I literally love how he keeps his videos real and entertaining.

[@saikatbishal]

Never had the hold of 'this' keyword until this video. Thanks much for clarifying my concepts.

[@KunalKushwaha]

Very welcome!

[@prakritimandal1722]

Kunal your playlist is more than awesome and Im too studying in a tier 3 college thereby your playlist is helping me to get to my heights. Mostly your podcasts are motivating me to grab those open source opportunities precisely I was into it from before. I want to say that try to avoid those controversies .

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[@ishitasingh6014]

The enthusiasm with which you are teaching is rare. My professor ought to learn the art of teaching from you.

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Love the way you're consistently bringing such an awesome content!💫

[@KunalKushwaha]

Glad you enjoy it!

[@sanskarbomble7554]

Awesome? Lol 🤣

[@vishalgupta7522]

Can i start this if i dont know p about programming will just start my btech ?????

[@heathens2867]

@@vishalgupta7522 yes

[@DHRUVSARASWAT-yy4jx]

​@@KunalKushwahaCan you tell me that how final keyword Makes Integer class immutable as final keyword makes class immutable not the object ?

[@4mitachi619]

the energy you bring while teaching is unparallel, loved the lecture i am lucky that i got to know about your channel at time 😍❣❣

[@mitaligarg4674]

pausing the video to appreciate your teaching skills. I have never been able to understand these concepts soo well. You are the most amazing teacher!

[@prernagupta7729]

Probably the best OOPs Playlist among all oops videos I have yet came across on KZbin.

[@KunalKushwaha]

Complete Java DSA playlist: kzbin.info/aero/PL9gnSGHSqcnr_DxHsP7AW9ftq0AtAyYqJ

[@its_SR07]

just for my future reff. 30:39 non initialize object give null as output 31:45 how obj gets created 39:11 just printing reference variable

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Your JAVA + DSA course is a boon for us, thank you for putting so much effort into making this playlist

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if I study java from here even I don`t know anything about coding will be enough for me to learn from here

[@gouthammurali5612]

I usually can’t watch long tutorial videos. When i started , this Playlist seemed to be long enough. But it was so easy to watch this and everything you taught is clearly inserted in my head now. Great content and amazinh teaching style. Keep going !

[@abhishekkabra3418]

loving the way u r teaching, loving the way u r pronouncing "instantiated". U r an inspiration for many of us, Thanks dude

[@sudarshan3901]

Crystal clear explanation of each and every concept.. Hats off to you man

[@arkashishsutradhar121]

class Kunal{ content=Amazing; cost=free; consistency=100% } Great explanation🔥

[@MahendraSahu-jh5sy]

I always get confused by "this" keyword, but after this video I completely understand why we use that, the way you are teaching is so much amazing thanks kunal 👍

[@AmitDubey-hi2sw]

are you sure you understood it well from this-> video 😂 . . . . . . jk

[@tilak5858]

Your way of teaching makes everything simple to understand...Thank you Kunal !

[@francovivanmichelon8647]

i was about to say this guy is on aderall when i realised i was watching on 1.5x since the beggining of the video. GREAT teaching skills. Learned 3 months worth of college classes in just a few hours with our videos

[@saumyadeshmukh6758]

Oh yes OOP is here 👍

[@hgfggjjgv]

Thank you so much brother..I am 2020 cse passout..I have 2yrs of experience in a support role... I am trying my best to do a pg course after leaving my job in September..this is helping me a lot to prepare before the course..❤❤❤

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Hi bro Really, Whenever I am watching your videos about java I feel that I am never give up because of your inspirational Talks and I highly appreciated how nicely and friendly your are explaining the lecture and Really, so nice for good communication of you language and simple way of talking . Thank you sir I am your subscriber but I see that best teacher I have ever watched his videos I can't mention in words How I am happy to have lucky to see your KZbin channel when I was looking where can i learn algorithms of java and solving problems related to java thank you many times seaph from Somalia.

[@annusingh4694]

Finally the video is processed! Thank you so much for these gems 💯

[@DHRUVSARASWAT-yy4jx]

Can you tell me that how final keyword Makes Integer class immutable as final keyword makes class immutable not the object ?

[@divyasreenalam7638]

I'm afraid of Java because of this oops concepts.but u made it easy for me.Thank you so much! Keep doing more.Also pls add a playlist on system design 😀

[@garvitabhateja405]

I always thought I didn't like programming. Little did I know it was because I never really understood it. Thanks for the video series it's been life changing. Never thought I could ever like programming this much.

[@kashifrahman]

I am falling in love with Java after doing this course . Thanks Kunal for this course 🤩

[@akshaysharma145]

Awesome! Maja aagya!! Even after going through paid courses, I was left with many doubts, however you already know what those questions in our minds are, and clear them with detailed explanation! Thanks a ton, am sure, I will be job ready after following you!

[@KunalKushwaha]

Thanks a ton

[@Sakshi01188]

@@KunalKushwaha please link the notes

[@Shubham_Ratnaparkhi98]

Comes with empty mind....going with overflow of knowledge....thank you buddy ♥️😍

[@rashimishra4556]

When he says I will not let you have any doubts he really mean it and prove it.💯😌

[@akshatchourey4441]

guys dont go any where else if you want to clear your concepts,this man is a legend ,he cleared my each and every doubt with this playlist

[@rahulchandran6482]

well structured, clarity at maximum level....concept building is so enjoyable...thank you kunal

[@sravanibulle3951]

Thanks a lot brother... U teaching skills are amazing...It helped me a lot to prepare for my interviews

[@sahilnikam2533]

Following this course from start. best playlist ever specially recursion and I know OOP will also best.

[@veerubabu398]

It's a great course collection. understanding soo clearly .their no such content in the KZbin like clear explanation on ech area ..Thank you much Kunal ❣️😍

[@manjarimistry5941]

I had always struggled with "this" keyword my entire life until today that I saw this video. Your way of explanation is hands down the best KZbin can offer on this date. Thank you so much for clearing all the concepts in such a nice and simple way!

[@KunalKushwaha]

Glad it was helpful!

[@heathens2867]

@@KunalKushwaha bhai reply tabhi deta hai jab use this->girl dikhta hai 😬

[@kartiksrivastava3897]

@@heathens2867 this guy has understood the 'this' concept at next level

[@aneeshp1556]

I have went through a number of courses offline and online too but plot twist was that NO ONE CAN EVER MATCH OR COME near to his excellency in teaching..Keep it up bro and keep teaching us as u.

[@KunalKushwaha]

Appreciate the feedback

[@Sakshi01188]

bro where are the notes @@KunalKushwaha

[@andrei6326]

Great video! Never seen someone explain this good! Thanks a lot, you are helping me go through my java classes. I wish I had professors like you

[@kazimostofasakin6166]

I am studying in Canada I try my best to understand in class practiced purchased so many courses but this playlist is something that I was looking for long time .

[@akshanshsharma7415]

brother , I am following this playlist for some time now It is amazing 😍😍 I request you to kindly upload videos more frequently so that I can practice java from your playlist without breaking the flow

[@VivekMishra-bl8zz]

Now feeling so good after watching this lecture Thanks brother.

[@KunalKushwaha]

Always welcome

[@s.saravanan5508]

Man your enthusiasm makes learners like us to get to learn more and more from you thanks for this good work bro

[@yashaswinin1054]

Thank you so much kunal!!! I always stepped back we it comes to programming. But after this video I'm getting confidence. You really have a good teaching skills!! I'm really excited to complete your playlist.

[@johar3737]

Thanks for giving us this detailed course on Java and the lecture on OOPS is amazing. The way of teaching is awesome.

[@KunalKushwaha]

You are most welcome

[@shivomgoddemonpanchal5460]

Sir I'm second year third sem student and I started learning from your dsa and java playlist and it is best in all youtube video I have saw but ur playlist are easily understandable even if we don't know any concept thank u so much for this content and also make video on linklist,stack, queue also please sir

[@KunalKushwaha]

It's my pleasure

[@sanskarbomble7554]

Hahahaha lol 🤣

[@heathens2867]

@@sanskarbomble7554 his name sanskar and harkate not so sanskari

[@vishalplayzz2580]

@@heathens2867 😂🙌

[@mohammadanas214]

The concepts explained are pure gold!!

[@BackEndGenius]

Thanks alot Kunal for your entended efforts. I came to learn alot of things in detail that I've been using for years & didn't understand the purpose before.

[@junaid_arif]

Finally started oops with you Kunal it's a great pleasure for me to learn from you The way you explain and point to everyone single concept is fantabulous 😇 Thanks a lot brother 😇

[@KunalKushwaha]

Glad to hear that

[@kashifrahman]

For learning OOPs should i have to learn java completely.

[@kushalroy9747]

@@kashifrahman nope only basics/ intermediate java is enough...

[@aravindhravi2307]

5 mins into the course I was totally hooked , I’m a dev with 4 yrs exp working in NA

[@KunalKushwaha]

Thank you so much for the support

[@aravindhravi2307]

@@KunalKushwaha keep going man great content!! Many will benefit out of it

[@jitendrasharma5474]

Really Kunal I am a automation tester , I really ur way of teaching impressed.

[@anubhavjoshii]

Awesome explanation Kunal, really love your hard work in these videos.

[@arunimasrivastava5527]

Dude you are an amazing Teacher. What you taught I have never received that quality learning from my entire College Life. Thanks to making us fall in Love with Coding. please make a playlist on Full Stack developer course also if you have the time.☺☺

[@Sriharsha_1729]

the notes part was missing in the git hub repo.. other than that the lecture was awesome

[@Sureshezhumalai]

Kudos to you for the hard work you put to educate the community. What are the others courses we can expect from you in the near future after completing this one, Kunal

[@KunalKushwaha]

Python, ML, DevOps and Web Dev are next.

[@NitinSharma-fh4ir]

@@KunalKushwaha laut aao Kunal Bhai 🐥

[@roshnaipodder5032]

​@@KunalKushwaha python, ML please

[@shaikismail55]

Explanation of oops concepts is simply amazing. Great work Kunal

[@shobham2941]

Thanks a lot brother, really learning a lot. Better than most of my College teachers !

[@Iam-qd9km]

Congratulations for the 100k subscribers 👍👍❤️

[@KunalKushwaha]

Many many thanks

[@abc5.-_]

Great Content & teaching, but where are the notes? I couldn't find them

[@rakeshkumarparida98]

I have watched many tutorials on OOP, but this playlist is unmatched.

[@tudinh9322]

best videos ever!!!! still stuck at these concepts and your videos are like my life saver

[@SaiRam-kq5gt]

What a brilliant playlist.. After searching lot and lot tutorials on on different platforms., Finally found this guy. There is no doubt at all. If a person is still can't able to understand java after watching this playlist., damn sure he never ever understands anywhere... Thankyou so much for your time kunal...

[@MUHAMMAD_AHMAD_JUNAID]

Do we have to learn basic syntax to java before ? Or we can start from scratch

[@-BCS-SahilTyagi-ro8zj]

NOTES PDF ARE INVALID IN REPO. UPDATE THEM

[@nabeelahmed7626]

started the playlist to land a job

[@sabrinanastasi5809]

Thank you so much for the precious videos! I will never thank you enough!

[@sathwikyadalam]

Great course brother! I am really interested to learn Object Oriented Programming after watching our lectures. Thanks a lot! 🙏

[@kqotes3942]

Brother which one you recommend to medium levelers(not experts in java but having some knowledge on java) i.e java+DSA playlist or this oops playlist ,which playlist u recommend to complete first ,pls tell me ☺️

[@KunalKushwaha]

both are same

[@gauribondarkar4178]

Kunal when u were struggling so much to say "instantiate".... 😂😂 that was so funny 😆

[@vishnupaswan1553]

Hello

[@praveenempire1642]

you are teach like experienced school staff ....after explain a concept you making one or two second silent that's remembering my school staff. That's good bro keep it up .

[@nishikant4689]

Best lectures on oops. Thank you bhaiya for providing lectures free. So much to learn from you❤❤❤

[@balajibala7508]

how to find the notes for oops??

[@ayushgupta531]

Hey Kunal , great lecture but i am unable to find the notes , can you provide the exact link of your github repo which directly links to java section notes. Thank you.

[@meghakeshri6945]

YEAH SAME WITH ME .IF YOU GOT NOTES THEN PLEASE SHARE THE REPO LINK

[@pavankumar-gp9zx]

did you got the notes, if yes please drop the link

[@pavankumar-gp9zx]

@@meghakeshri6945 did you got the notes, if yes please drop the link

[@PavanKumar-tt6tw]

Your explanation is very crisp and easy to understand. Keep doing the good work dude.

[@mkhadka123]

I'll never have a doubt again regarding these concepts

[@rupanshyadav3909]

Bhaiya when are you completing the entire course? Thanks.

[@KunalKushwaha]

this month

[@aarushaverma9687]

where are the notes? i cannot find them on the github repository. please help

[@boomam4383]

I am also can't find notes

[@dineshs2484]

​@@boomam4383 It's the white board thing which Kunal uses through out the lecture I guess.

[@Rajyadav-yh3rz]

Really amazed by these concepts. Thankyou so much Kunal for delivering this amazing content.

[@mohdkaif864]

you struggling to say instantiate is the most relatable thing I have seen in ages. Anyway, Thanks for making such an awesome playlist. more power to you

[@sunnydewangan2212]

Whenever you create an instance of a class, by default, in heap, class properties are initialized with their default values. When you use dot (.) operator to access them, it never checks whether there is any value associated or not, it simply fetches whatever the value is. So, to me, it seems at the 43rd minute the explanation is slightly misleading.

[@marc8150]

Is it possible that you, in the entire playlist, did not even mentioned getter and setter classes once? If that's true, why? I thought they are very important?!

[@KunalKushwaha]

It’s covered

[@marc8150]

@@KunalKushwaha Okay great! Just finished the second part and wondered where are getters and setters? :D Then skipped through the other videos and couldn't find them, so I thought I'd just ask. Great guide so far. Probably the best OOP course out there and all for free, good job man!

[@BrayanLledes]

I agree with all the comments, if not the best playlist to learn!!! (I am a complete beginner and have understood everything easily)

[@jyotigupta6756]

Great great great concept clarity, please continue sir. Falling in love with Java 😇