Get a Taste of Lambdas and Get Addicted to Streams by Venkat Subramaniam
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- Опубліковано 28 сер 2024
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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.
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()
Awesome toc 👍☺
Very informative and well explained, thank you.
You probably made it for yourself, didn't you ;)
@@infitium7246 yes, i have bad memory, so jot it down make me remember better :)
Hats off!
Venkat is not just really knowledgeable but he knows how tell and express concept in the way even a kid could understand . Thanks .
2w
@@veenasharma2440 from india?
@@udaykiran557 from india?
@@satishsatyan3520 Yes
@@udaykiran557 .
One of the best java talks ever seen.
Very informative.
短短的看到哦的哦地盘耳畔网片 W_PP_W_PE_PE_PE_PD
agree
The best java talk I've ever seen
me too...:)
.
Same here
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.
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. ☺
youtube rocks
The best speaker I've ever heard. I am delighted
1:02:40-1:05 the heart of programming! Great talk!
Best!
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!
This guy speaks very well. Usually indian guys are hard to understand. This guy is awesome!
A rare species : someone who can do tech, can talk and also keep you engaged for a full 3 hours.
I have been converted to functional style programming using Lamdas and Streams thanks to Venkat.
Double thumbs up!
This is how you explain advanced stuff in simple way. Tell me why i should bother to use a new feature. Amazing.
What a great speaker.
Really amazing. I am a big fan of Venkat. His book "Functional Programming in Java" is also a must read for all Java Developers.
Thanks for comment, I needed some book as a guide.
Well he said you came here for Lambda but stayed here for stream but I got addicted to Venkat. Amazing speaker. Thank you.
"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
HEX D
This is hands down the best Java conference evere made
Love his enthusiasm and his crisp and clear explanation.
superioriginality = qualities.reduce(blessing, (feature, excellency) -> feature.add(excellency)); Dr. Subramaniam rocks as ever. Thank you for another great session !
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.
Just watched 24 mins and gave my like to the video. What a speaker, cheers!!! -)
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. ❤
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....
Cant believe i just listen through the whole video...
He is brilliant teacher
he is best at explaining things...became fan of him.
I'm fortunate to watch this video! Speechless.. Absolutely recommended for people like me who didn't know the potentials of lambdas and streams.
This guy is a great speaker! Thanks for the awesome talk.
Really an awesome talk,the way you explained with real time examples and jokes is really superb. You made Lambda and Stream learning so easier. Pleasure to saw your teaching and Gonna see all your talks in you tube. One of the best java talk ever ! Thank you so much Venkat
Buddy, I caught you here. I even like the talk. best ever java talk
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
Indians are awesome! thanks, Venkat sir.
What a great talk, Venkat gave the best explanation about streams I've seen, and I've seen quite a few so far.
just came to learn lambda.... never had a blast before learning programming concepts
One of the best java talks I have ever scene that even a beginner can understand it...
I sincerely wish I could like this video more than once. Simply brilliant
Indeed a great talk on lambdas and streams. If you have been coding in java for a year or more , then you could even watch it at 1.75x without losing on any info
I had come to see this video to brush my knowlege. I ended up learning many new things. excellent explaination
I just love that editor and how intelligent that thing is! Venkat should do just one nice session on that editor setup. That would help the community so much :)
Did you find that already?
@@kpvenkatesan Its TextMate
Great talk, very informative for those who are starting to work on java 8. Awesome explanation.
Fantastic presentation! What a great speaker! One of the best presentations that I've watched.
As the title says, I addicted to Stream; But I addicted to your lectures more than it. Thanks Venkat, it was really helpful.
His pace of explanation is perfectly suitable for me
"A person who uses all the tools are called consultants" (1:05) - hahaha, you made my day sir!
Brilliant. Best value for 2 hours spend watching the video
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. 😕😕
This is one of the best videos that I saw about Streams and Lambdas!!
Wow, not sure why I didn't use of java 8 functional style until now. Great talk
one of my favorite features was "replace lambda with method reference", until i started watching this videos
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 !!
GREAT!!!! so many details! so many examples! awesome! thank you a lot!
"If a language does not support backward compatibility, it is DOOMED; we also know if a language supports backward compatibility it's also DOOMED!... and so it's a question really choosing which way you like to be DOOMED!"
LMAO!
There's a lot of crap in his talk apart from the actual content, which wastes my time. I am better off reading a book than watching his talk.
Just upgrade and move on.
make your nuts tight!
Venkat is brilliant. Indian minds are like gods.
its about perceiving and realizing. Not blind mugging.
your one of the best teacher I have seen till now..
Brilliant analogy !!!, I wish I could give Super Like or more likes to this talk :-)
Here, still in 2023
In 2024*
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
Been 6 years and it's still useful :)
Venkat is an awesome teacher! Thanks a lot for sharing!
Thanks a lot for such a informative talk.. watched entire 2:47 hours
He is amazing!! Best Java talk ever
1:15:48 "If you gonna take so long and suck , you would rather suck quickly." Lol 😂.. man that was damn hilarious..
think new session required to introduce ide 😁, very impressed. thanks a lot
Am binge-watching presentations by Venkat.
how to speak about a boring thing in a very brilliant way ... and in white socks ... amazing !
Claps for your passion for programming especially for your comments at 1:00
Finest explanation on streams. Thank you very much!
The Best java talks i have ever seen...
gc() those unlikers...
Amazing lecture on functional programming. The best I ever heard!
And with no shoes ... love u bro !!!
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
Awesome. Excellent presentation. I wish I have seen this earlier. Recommend.
Thank you so much, Venkat!!!
If(true){
return "Sir you are the best .Salute!"
}
Venkat is really becoming my code hero
This man is really good at talking and explaining
Great explanation with great examples... Thank u for giving me the imp of lambda & stream.
Its really a very good talk!!! The way concepts presented helps understanding it from the core.. Great job sir.
Awesome sessions. Java made easy and interesting. Excellent speech.
While explaining the time taken by for loop in finding the value of even number greater than 3 and multiplying the same by 2, Venkat explained as if the for loop goes through all the values before giving the result. The explanation of men in black T shirt, white shoes etc., strengthen this impression. As someone, mentioned a break statement at the end of the for loop as soon as the required number is found, then the for loop will stop functioning. No doubt writing a stream function is easier and clearer than writing a for loop. For loop does take more time than the stream, no doubt, but the explanation needs modification.
Thank you. It is such informative video and I really love the way you present it.
Content and the way it is explained is nice. Thank you.
He's so awesome, thanks for the talk!
Venkat , you are simply amazing.. Great talk!
Awesome explanation, wondering about people who disliked this video
What entertaining educational talk, thoroughly enjoyed!
Venkat Sir The presentation was nice. But the way you were advocating lambda's saying the old code sphagetti I am unable to understand that because the one thing I like the most about java is when I read the code I can logically deduce what is happening I am not playing the guessing game for type of variable and class being called. Its definately powerful and it will make our life easier. But in my opinion the readability of code matters more than the size. Java was never a rapid prototyping language for small programs python is.
Thanks a lot this man is competent,
Small mistake on 1:43:00 the first param of reduce is actually R not T. the same as return type.
Really, really, awesome!
Really finding it very interesting and glued.
Awesome presentation. Truly gifted at explaining concepts
Very Consuming.Awesome video
Very dynamic person!!
34:48 "So for the first time in a long time, Java is finally intelligent." LOL
Amazing explanation. I ever scene this kind explanation
1:06:00 One of the best explainations
This video is gold.!
Great Job!!!!
Very clear and useful informations, very grateful for them. A question though: isn't also type inferrence when you only have to write List cars = new ArrayList() instead of List cars = new ArrayList()? - you are saying that Java 8 has type inference only for lambda expressions...
Best Talk Heard Yet!
you could further create your own methods and call them like: "numbers.stream().map(ToString).reduce("", ConcatWithCommas);", even you could prevent adding the first comma when the accumulator string is still empty inside ConcatWithCommas
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you are a walking java god