Get a Taste of Lambdas and Get Addicted to Streams by Venkat Subramaniam

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The first thing visible in Java 8 is the lambdas, but the real power is in Streams. If you're interested in immersing into lambdas and streams, this is the session for you. We will start with lambda expressions, learn about how to use them and how they get implemented under the hood. Then we will swiftly move into learning about streams, the abstractions they provide, and a variety of operations we can do with them. We will conclude with a discussion about lazy evaluations, infinite streams, and parallel collections.

[@ruixue6955]

7:00 lambda 7:26 backward compatibility of Java 8:18 9:34 why Java 8 is backed by single abstract method interfaces (@FunctionalInterface) 9:47 if an interface is single abstract method interface, you can use lambdas instead of anonymous inner classes 11:47 how does it work under the hood 12:49 illusion aobut lambda - syntax sugar, i.e. on the instruciton level, it is the same as anonymous inner class 14:16 what lambda does under the hood 14:47 what would the compiler be doing with lots of lambda (assumption only) * 18:16 why it is not a good idea for lambdas to create extra classes like anonymous inner classes 19:14 a new feature since Java 7 - instruction - invokedynamic 20:53 in Java 8 struggling with the elimination of anonymous inner classes 21:00 the motivation: use invokedynamic to implement lambda expressions 25:16 example 29:18 internal iterator 39:00 method reference 44:28 avoid the urge of writing a large lambda expression - an anti-pattern 44:54 what are method references 45:41 examples of method references 47:15 static method reference 49:31 parameter as a target map(String::toString) 54:58 2 arguments * 56:23 the order of the arguments are important 57:38 another example - first parameter is the target, second parameter is the argument 59:33 limitations of method reference 1:08:00 filter 1:19:30 second part 1:29:07 stream is an abstraction 1:29:12 a stream is not a physical object with data 1:29:24 a stream is a bunch of functions you will evaluate eventually. There is no data sitting in a stream 1:29:48 a stream is a non mutating pipeline - stream is not mutating the data in a collection 1:30:31 stream functions 1:33:11 transforming function - Stream.map 1:37:25 Stream.reduce() 1:43:47 InStream/DoubleStream.sum() - also a reduction operation 1:44:08 what is reduce operation - transform a collection into a concrete value or object 1:44:51 another reduce operation - collection 1:45:45 a wrong approach to do collect 1:47:00 explanation of the wrong code 1:47:18 shared mutability is devil 1:49:04 use Collectors.collect 1:51:17 Collectors.toMap 1:54:17 groupingBy 1:54:38 example 1:57:40 another example with mapping() method 1:59:37 performance 2:05:40 Q: How much work? 2:09:30 streams are LAZY 2:10:49 intermediate operations are postponed for evaluation 2:13:00 important * 2:15:43 * 2:16:15 2:17:37 demo for performance analysis 2:19:36 lazy evaluations are only performed when the terminal operation is triggered 2:27:08 intermediate operation - Stream.sorted()

[@raghavanaliassaravananm1546]

Awesome toc 👍☺

[@MrNaveen303]

Very informative and well explained, thank you.

[@infitium7246]

You probably made it for yourself, didn't you ;)

[@ruixue6955]

@@infitium7246 yes, i have bad memory, so jot it down make me remember better :)

[@tahniat]

Hats off!

[@trozzonick77]

Venkat is not just really knowledgeable but he knows how tell and express concept in the way even a kid could understand . Thanks .

[@veenasharma2440]

2w

[@udaykiran557]

@@veenasharma2440 from india?

[@satishsatyan3520]

@@udaykiran557 from india?

[@udaykiran557]

@@satishsatyan3520 Yes

[@satishsatyan3520]

@@udaykiran557 .

[@vaib5917]

One of the best java talks ever seen. Very informative.

[@pacegeorgia7200]

短短的看到哦的哦地盘耳畔网片 W_PP_W_PE_PE_PE_PD

[@vkolodrevskiy]

agree

[@xvitcoder]

The best java talk I've ever seen

[@jaikeegupta3711]

me too...:)

[@rviyadav4726]

.

[@virendrapatel775]

Same here

[@AsifAlli]

This guy speaks very well. Usually indian guys are hard to understand. This guy is awesome!

[@pksanthoshkumar]

Amazing lecture on functional programming. The best I ever heard!

[@jcraane]

I created an IntelliJ plugin which provides similar functionality which outputs the result of a Java main execution as a tooltip. The plugin can be found here: plugins.jetbrains.com/plugin/8543?pr=idea

[@TheRastaDan]

34:49 "And for the first time, in a long time, Java is finally intelligent" that was the moment I lost it. This guy has such a talent of explaining stuff!

[@judgeomega]

What a great speaker.

[@h1dden_]

Venkat was my professor at UH for my last year in computer science. He is by far the BEST computer sceince professor I have ever had. I learned more from him in one semester than I did from when I started coding in highschool.

[@MuscleTeamOfficial]

This guy is a great speaker! Thanks for the awesome talk.

[@sdevane75]

finally, someone intelligent and articulate enough with great dynamic working examples explains lambda and double colon. thank you. after much searching its finally clear to me. ☺

[@corabora6644]

youtube rocks

[@durgadeep4988]

Love his enthusiasm and his crisp and clear explanation.

[@oleksandrdyachuk3951]

GREAT!!!! so many details! so many examples! awesome! thank you a lot!

[@RobsonDev]

Fantastic presentation! What a great speaker! One of the best presentations that I've watched.

[@manojkumarmurugan5808]

He is amazing!! Best Java talk ever

[@TheMinino123]

Thank you so much, Venkat!!!

[@usamaiqbal9933]

One of the best java talks I have ever scene that even a beginner can understand it...

[@kovalski6000]

The best speaker I've ever heard. I am delighted

[@mirageman2]

What a great talk, Venkat gave the best explanation about streams I've seen, and I've seen quite a few so far.

[@ddhirajkumar]

Like this talk and the way of communicating some of the design philosophies. Not just what can be done.. but also the why and how of it is covered here.

[@bikejoede]

Venkat is an awesome teacher! Thanks a lot for sharing!

[@freezefrancis]

Venkat , you are simply amazing.. Great talk!

[@jineshshah566]

Finest explanation on streams. Thank you very much!

[@sunilchandramn3001]

your one of the best teacher I have seen till now..

[@sahilrally4491]

Just watched 24 mins and gave my like to the video. What a speaker, cheers!!! -)

[@arsalalam5998]

This is how you explain advanced stuff in simple way. Tell me why i should bother to use a new feature. Amazing.

[@susaninj]

Awesome. Excellent presentation. I wish I have seen this earlier. Recommend.

[@shailendra-mani]

Great talk, very informative for those who are starting to work on java 8. Awesome explanation.

[@giddaiahkummari2249]

Hi venkat, I referred so many author's to understand java8 features, but some how I got ur video in the list. I just looked into it, it was just awesome. Thank you for ur efforts

[@ketkithosar7465]

I sincerely wish I could like this video more than once. Simply brilliant

[@weipingguo6038]

Great talk, very informative with great details!

[@caiboliang5568]

think new session required to introduce ide 😁, very impressed. thanks a lot

[@harshavmb]

I'm fortunate to watch this video! Speechless.. Absolutely recommended for people like me who didn't know the potentials of lambdas and streams.

[@chintangandhi4500]

I had come to see this video to brush my knowlege. I ended up learning many new things. excellent explaination

[@sanjuro_493]

This is hands down the best Java conference evere made

[@cong0929]

Wow! Great explaination of Lambda and Streams. His explaination and examples are so concise and easy to understand that I've ever seen. Very very thanks !!

[@ramesh040580]

Content and the way it is explained is nice. Thank you.

[@sahilrally4491]

Brilliant analogy !!!, I wish I could give Super Like or more likes to this talk :-)

[@diasneto5231]

Really, really, awesome!

[@mangasreekanth]

Brilliant. Best value for 2 hours spend watching the video

[@jyotikabra72]

he is best at explaining things...became fan of him.

[@LauriusT]

Wow, not sure why I didn't use of java 8 functional style until now. Great talk

[@KinGxWolF]

Awesome presentation. Truly gifted at explaining concepts

[@akossarnyai4978]

This is one of the best videos that I saw about Streams and Lambdas!!

[@alok0412]

Simply awesome!

[@alex771304]

Thank you. It is such informative video and I really love the way you present it.

[@hastingr]

1:02:40-1:05 the heart of programming! Great talk!

[@harishgovindarajan9983]

Best!

[@VinayakPanchal007]

Great job Mr. Subramaniam !

[@bhadreshagm7692]

Its really a very good talk!!! The way concepts presented helps understanding it from the core.. Great job sir.

[@prateek6424]

I just can't express how glad I am to land here. He has explained java 8 features with so much depth and conviction. Venkat sir just knows the features inside out and he is in love with Java. ❤

[@sherif_a]

Very dynamic person!!

[@daddashikamani]

I have been converted to functional style programming using Lamdas and Streams thanks to Venkat. Double thumbs up!

[@zeroxcub]

Really like the part with the performance analysis, most video about FP stop on the declarative part and don't go further. Thanks Sir, you got my like

[@DanielHorrisberger]

Great Talk! As always from Venkat

[@tryfonmichalopoulos5656]

This presentation was magnificent !

[@satishrock9621]

Awesome Explanation Sir. Thank you so much

[@walterdiaz2003]

This video is gold.! Great Job!!!!

[@bangladeshibadmintonny]

Well he said you came here for Lambda but stayed here for stream but I got addicted to Venkat. Amazing speaker. Thank you.

[@SourabhBhat]

Wow!! Such an amazing talk.

[@balucse019]

Great respect to you sir 🙏🏽

[@brave111111]

Awesome sessions. Java made easy and interesting. Excellent speech.

[@vipulchauhan5317]

Thanks a lot for such a informative talk.. watched entire 2:47 hours

[@velganesh30]

You are one of the very best.

[@epsilon21001]

He's so awesome, thanks for the talk!

[@shekharkumar78]

Really amazing. I am a big fan of Venkat. His book "Functional Programming in Java" is also a must read for all Java Developers.

[@ggsay1687]

Thanks for comment, I needed some book as a guide.

[@jvsnyc]

One of my new favorite speakers ever. It's all gold, but the motivational parts especially, even tho the technical details are all spot on and valuable. Like 1:02 thru 1:05, not strictly technical, but extremely important in terms of WHY we need to modernize our Java style....

[@masterprattu]

One of the best java talks!!

[@ThueringerNeuland]

This man is really good at talking and explaining

[@edukondalugumma3753]

Amazing explanation. I ever scene this kind explanation

[@SharanSatkhed]

GREAT!!! Awesome presentation. Thanks a lot...

[@KushalMaharana]

I learnt a lot from this video thank you!

[@AkashSingh-el1ew]

Been 6 years and it's still useful :)

[@tharindusathischandra9533]

As the title says, I addicted to Stream; But I addicted to your lectures more than it. Thanks Venkat, it was really helpful.

[@anilreddy1613]

His pace of explanation is perfectly suitable for me

[@terreur35]

really great, and amazing presentation

[@akashkadole3034]

Great explanation with great examples... Thank u for giving me the imp of lambda & stream.

[@drakezen]

Really good presentation!

[@gauravagrawal7614]

Really finding it very interesting and glued.

[@LorenzoCrippa76]

Great lesson! Thank you

[@gurucharansharma5574]

Simply Amazing!!!

[@newnewdaniel]

Thank you for the talk.

[@hirenpandit8499]

"When you have 9 million programmers using your language and out of which 1 million programmers know where you live you have to decide things differently." :D

[@GawblyOG]

HEX D

[@parthdalvi5855]

Simple and outstanding explanation !! :-)

[@Tikeswarib]

What entertaining educational talk, thoroughly enjoyed!

[@aaratprasadchopra3255]

Best Talk Heard Yet!

[@osayamenomigie]

Cant believe i just listen through the whole video... He is brilliant teacher

[@thyagtubes]

A rare species : someone who can do tech, can talk and also keep you engaged for a full 3 hours.

[@sagarjadhav5429]

best java 8 presentation....

[@dostanik01]

Awesome talk!!!

[@vikasmessi]

Brilliant presentation.

[@chandrabhoopalr8008]

Wonderful speaker.. amazing analogies

[@trile2713]

superioriginality = qualities.reduce(blessing, (feature, excellency) -> feature.add(excellency)); Dr. Subramaniam rocks as ever. Thank you for another great session !

[@nimishgupta749]

Flawless speaker.

[@abhishekgowlikar]

Good explanation Hats off

[@KiranVuyyuru]

Great talk; nice illustrations.

[@guedim1982]

Great Post.

[@rajeshkumarpatel5068]

Nice explanation sir... Very informative.. I would say I have never attend any tech show.. Where someone explained like this during my entire career.. Lol now I got it what was missed in my eduction. 😕😕

[@shaheenjamadar1933]

Awesome session .. thank you

[@sandesh4063]

Just awesome sir 🙏🙏🙏❤️