OOP 5 | Abstract Classes, Interfaces, Annotations

This fifth video of the complete object oriented programming (#OOP) course in Java will clear some of the most important concepts for you about multiple inheritance.
Covering abstract classes, interfaces, annotations, and more!
Complete OOP playlist: • Object Oriented Progra...
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=========================================
Timestamps:
0:00:00 Introduction
0:00:30 Multiple Inheritance Problem
0:01:08 Abstract Classes
0:06:38 Example of Abstract Classes
0:16:45 Abstract Constructors
0:17:15 Object of an Abstract Class
0:17:40 Abstract Static Methods
0:18:04 Static Methods in Abstract Classes
0:21:52 "final" Keyword in Abstract Class
0:24:18 Multiple Inheritance using Abstract Classes
0:25:10 Interfaces
0:31:29 Example of Interfaces
0:43:41 Variable of Interface Type
0:47:42 Separate Classes in Same Interface
0:55:01 Extending Interfaces
0:57:18 Annotations
1:02:05 Important point regarding Static Interface methods
1:06:17 Nested Interfaces
1:09:31 Outro
#placement #dsa #interviews

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[@KunalKushwaha]

Thank You 🙏

[@jayprakashjaiswaldeptofcom1250]

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[@Cono314da]

@@KunalKushwaha at 23:15 why cant it be "final int VALUE = 30;", rather than value being initialized in the constructor?

[@vinathasree168]

@@Cono314da can't be inherited, so we put it in a constructor to initialize it

[@shubhamagarwal7876]

Kunal I am having 2.5 years of experience in IT and now preparing for a job switch. I am following all your videos religiously. The content you are providing is just priceless. Your way of teaching is so lucid that nothing else than series is required. I am so much enjoying it like a web series , and yes learning was never so much of fun. I India I think we need no college we only need Kunal to make quality engineers. In college they cannot make these these things clear in 4 years and you did it in just 40 min. God bless you . Keep sharing your learnings .

[@akshaytakrani6886]

Ocean of knowledge in this video about Interfaces and Abstract classes. Love the way you teach ❤

[@KunalKushwaha]

Thank You

[@jomamusk9791]

There can never be a better example than the MyCar Example. What and example! Most concepts Kunal taught till now are there in this single example. You are the Best!!!!

[@KunalKushwaha]

Thank You!

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exact at 12:13 Kunal just thought of his love😍

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[@flyfly11111]

Hi Kunal, I recently founded your channel, I like the way you explain the core concepts. It's really very helpful. Thank you so much. Please keep this continue

[@avinashsingh7722]

Thankyou so much Kunal this is the best video i found on abstract classes and interfaces. Learnt a lot from this. ;) Message to fellow people just stay away from involving in controversy. Our main motive should be to learn from anywhere we can. Thankyu kunal for providing top-notch content on OOP.

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Fell in love with your consistency and knowledge sharing.👏

[@S_SwasK]

Got a bit confused in the Car Engine Brake part , had to rewatch that part 3 times , but understood well practicing with you , Thank you for in-depth Explanations and not just another Tutorial.

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there is no one making such a detailed video like you did.

[@TuxTuxedo-oc9kg]

this is the most awesome java tutorial I have seen on youtube so far. thank you so much!

[@parth_chovatiya]

1:02:11 Static method can inherited If you declare, another static method with same signature in derived class than the static method of superclass will be hidden, and any call to that static method in subclass will go to static method declared in that class itself.

[@uditbhaskar]

Nice joke buddy, good luck with java.

[@mohanprajapati2051]

@@uditbhaskar The only difference with inherited static (class) methods and inherited non-static (instance) methods is that when you write a new static method with the same signature, the old static method is just hidden, not overridden. If you declare the same method in a subclass, you hide the superclass method instead of overriding it. Static methods are not polymorphic. At the compile time, the static method will be statically linked.

[@yashsingh3040]

@@uditbhaskar good luck for your java.

[@uditbhaskar]

@@yashsingh3040 Rip english

[@applein289]

You don't have to mention it that u have to create this course to be the best on youtube, because it is. By your videos i get detailed info of every topic, Loved your course😍

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Best OOPS videos on the internet!! More power to you sir!!

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ngl this is the best DS and java course I've ever seen. tbh I'm struggling a little bit but ig i need to do more practice and exploring

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[@ManhwaXin]

Brother, you video are the ones help me the most understanding OOP.

[@yogpooja-vq1pp]

Thank you, Kunal. and yes it is the best, I have ever found.

[@Helly_Patel]

Thanks for teaching us like no one did till now!! One small request, please make lectures on dynamic programming as well!!

[@lohithkumar5292]

Great content! Looking forward for future videos.

[@2KHuman]

Kunal bro your teaching method is another LeveL and also your are way better than IIT, NIT Professors 🔥

[@KunalKushwaha]

Maine bhi suna hai ki kaafi IIT ke professors ko padhana nahi aata. Not saying all, but majority. Might be some good ones too.

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So many doubts got resolved with this playlist, Thank you Brother 🙏.

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Bro what a tutor! Amazing.. You really made me fall in love with dsa..

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Best Explanation, Best Course by the One and only Hero Kunal. Thank you

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The best OOP Playlist in java

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Your dedication ❤️

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Thanks for sharing your valuable knowledge free of cost😊 wishing you d best of best🙏

[@usenmfonuko3271]

Thank you so much Kunal

[@34adnanali26]

this is free and so useful for interviews prep

[@subhrajyotidas2569]

that car interface explanation was just fabulous!

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best teacher ever!! hats off..

[@amanjain0842]

great great great explanation of Interfaces using examples

[@devesh819]

You literally rocked it man two two blockbusters in a single day ... Hats off too u for consistency again 👍👍

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This has been the best DSA course so far for me, I have never loved OOP before🤗

[@user-jy1yu4kz9p]

Notes bhej de bhai

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all are awesome lectures

[@abrarfaisal1393]

Hey kunal, a lot of appreciation man, did a great job. But its' hard to wait for upcoming videos for advanced algorithm, DP, trees and graphs videos etc.

[@BackEndGenius]

Best explanation on Interfaces.

[@_hulk748]

Great Explanation Sir✨❤ Please continue the DSA series Sir🙏🙏

[@muhammadumair6443]

i failed in my interview because i did not come across by your channel. I did not know all of the concepts you have taught in this video and interviewer was asking all of these stuff. Now, i will ace that interview next time :) Thanks alot. Best series ever!

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What can I say another great content like everybody knows.🙌

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Simply amazing.

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As always the best one !!

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Thanks Kunal 🙏🏽

[@tejasdeore8340]

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[@KunalKushwaha]

how do I get in touch

[@tejasdeore8340]

@@KunalKushwaha don't know if my comments are getting deleted or what . But unable to see posted comment 😰

[@KunalKushwaha]

not at all, see I liked it too

[@tejasdeore8340]

@@KunalKushwaha I don't know why but my comments are getting disappeared automatically . I dm u on instagram please do check. Bro for privacy reasons my comments getting down . Unable to share address and email here so have dm u on instagram.

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Not only OOPS bro , DSA also though some topics like graphs &heaps are not covered. We are waiting for these videos🙃

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You are Probably the best., thank you🤗🙌

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Great explanation in easy to understand manner...thanks @kunal

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Amazing video Kunal! Tysm! Hope that one day, I can also be almost as good as you 🥸

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The best video.

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Great content as always

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Thanks Bro, It Helps me a lot.❤

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this is the best oops playlist

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great to have this..

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Thank you kk...you are awesome

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Thanks kunal 🔥🔥

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Man you're incredible 2 videos in a day!🙆🏻‍♀️🔥 Hats off to your dedication ❤️

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Good video. Explained it nicely.

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simply amazing

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Thanks a lot for these videos

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thank you so much!!!!!!!!!!

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Thanks Kunal

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Love the content. Man literally thought for eternity before putting up a girl's name and finally gave up. True developer moment.

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Dsa in 15 days!..plz continue..placements going on

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You're really a cause of prideness of India..

[@mandarpandit8786]

Thank you Kunal ;)

[@anjalithakur_12]

Great video enjoyed it

[@Cono314da]

@KunalKushwaha, at 23:15 why cant it be "final int VALUE = 30;", rather than value being initialized in the constructor?

[@yashkoolwal196]

killed it dope explanations helped me a lot!!

[@xzist2342]

Thanks alot

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From TamilNadu 💥😘 I Have Complete OOPS in Java , I Like Your Teaching 😅💥

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Don't worry I am with you ..

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me too followin for bout 2 years now came to revise these topics

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Nice one ❤

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Thanks for your explanation in English....

[@Student-zc7hb]

Sir thank you so much 🙂😌

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Great video.

[@432prameela3]

Thank you ❤️

[@vishalkumaranand3279]

47:50 Brother, if you made different classes that implements different interfaces then how it remains multiple inheritance ,what was the purpose of interfaces? Please explain.

[@Peter-00.02]

worth to watch.

[@donrenachinedum6079]

Thanks

[@DivyanshGemini]

@KunalKushwaha *Not getting AutoGenerated English subtitles in any of your video.* (May be due to video language set to Hindi)

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Good One 🤟

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thank you very much

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thank you

[@vineela-meduri]

Hi Kunal, can you please include topics related to comparable, comparator, finalize and finally??

[@anubhavgarg1728]

At 50:20 I wanna know why did we create a reference of Engine interface in NiceCar class? I have a possible explanation but not sure if it is right. According to me we did that because we have also created a constructor which instantiates the engine interface reference to an object of a concrete class which has implemented the engine interface. Thus, if we simply create a reference of engine interface then we are going to be able to assign it to an object of any class which has implemented the engine interface eg Upcasting will handle the implicit casting of an object of a class type such as ElectricEngine to a reference of Engine interface. In other case if we create a reference of class such as powerEngine then at the instantiation time when we try to access the constructor and assign this reference variable to an instance of Electric Engine type, it will simply display an error.