Design Patterns in the Light of Lambda Expressions by Subramaniam

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We all have used design pattern in Java for decades. Most of those patterns were influenced by the capability of the language. The capability of the language, however, got better with Java 8. With lambdas, we will use some design patterns differently than before. There are other design patterns that we can use now that were beyond reasonable reach before. If you're into design patterns, what to up your skills on applying patterns with lambdas and related capabilities in Java 8, see you at the session.

[@trevorcoleman9125]

These presentations are gold mines of wisdom. I get about 200% smarter every time I listen to one, but I have to take breaks because the pace is relentless. Talks need breaks, the same way flights of stairs have landings. Just a short break to breathe for a second.

[@testamento13]

Ok I am officially addict to streams and Lambda expressions :)

[@virendrapatel775]

same here

[@littlethings2250]

You don't like lambdas & streams great!! Stay there till the end. Now? Thank you for some real good stuff and importantly the way it is presented👍

[@CenturionDobrius]

this guy is simply amazing !!! thank you Venkat for everything you do, and thank God that used builder pattern when creating you, and like in mailer example, setting up all those "andThen()" on you : knowledge, energy, interesting examples, humor, which you successfully apply in your stand-ups :)

[@neozoan]

Holy crap! Venkat knows my grandma!

[@crabsynth3480]

Excellent Lecture... The Presentation is simply Flawless, highly Informative and Entertaining!

[@suninsandeep]

must watch presentation even after 7 years .

[@EnricoGalassi]

What a great video! Excellent look at some of the design patterns with the newest language features!

[@GauravRawat14]

love most of Venkat's presentations ..this is great coding while listning to this

[@TheTubeThomas]

One of the best presentations of Devoxx 2015 - enjoyed it so much.

[@wwhill8033]

You are amazing in the way you explain and present!! Thanks so much

[@GijsSijpesteijn]

Excellent, now see the places in my code where I can use it. That could be a challenge

[@josephmukorivo484]

Wow best teacher ever thanks venkat

[@tobiaspreuss]

Thank you for your great talk!

[@sthoyyeti]

Venkat Sir, you are right on the money!

[@pawelmagnowski2014]

1:54 the same goes for Agile, DDD etc etc. But it will take another 20y for managers and "enterprise architects" to get this

[@bishbashboshjt]

This guy is a great teacher

[@ahmetyasarozer]

Huge thanks. Best wishes.

[@waqasrana7891]

just awesome presentation by venkat ever

[@olegnovitskiy1098]

Awesome! Thanks.

[@strictnonconformist7369]

I especially like the “execute around method” pattern, garbage-collected language/runtime or not, making sure things always get cleaned up properly is a nice thing to force the users to do by design making it easy and forgetting it impossible because the compiler won’t let you use it where you could forget.

[@sourabhhsethii7292]

I started loving it. Functional Programming

[@CivilNL]

Awesome talk!

[@samuelasmelash8719]

great content as always.

[@meriemkaroun7626]

You re awesome! Please, do not stop doing such a great job :) (big fan)

[@Aaradhyannair167]

Superb. You are just amazing

[@dancodrean01]

man you are amazing !

[@multigladiator384]

Great practise.

[@kamesh7818]

loved it, as always :)

[@pavanagrahari694]

So great sr

[@KDOERAK]

a great talk

[@MuscleTeamOfficial]

Thanks VSub

[@jiteshsrivastava5808]

I like it.

[@neetamlimbu5335]

Awesome

[@jorgetovar621]

I really like your videos but I think that can be useful to specify the proper article in the agile downloads

[@leeyomwang1834]

so cool

[@metachronicler]

First minute or so is gold. I would only add that design patterns in some cases are probably indicative of a flaw in the design of a language.

[@krishnasharma353]

I think caught you very late but not too late. I became a big fan of you, the day I watch one of your conference talk since then almost going through all the conference talk and blog. By doing so I am getting addicted with this. The way you explain the problem giving with real world example(like in hotel you were asking for watch and receptionist was insisting you that you need an alarm. and many more) and some funniest talk in between it's not making us to get bored even watching 2-3 hour of video. You are genius, Keep doing. I have a small doubt if you get time to reply Can we still maintain the immutability using cascading(cascade method pattern) possible alternative of Builder pattern? Example, in the given Mailer example if I change method signature of 'send' like below public static Mailer create(Consumer block){ // I want creation of object to use somewhere else but only getters should be accessible Mailer mailer = new Mailer(); block.accept(mailer); return mailer; } And the caller side they will call /** I want this Mailer object some other functions/classes**/ Mailer mailer = Mailer.create() ; mailer.anySetterMethod()// shouldn't do that, that's fine we can create all members as private final, but if we do that then how will access in lambda expression Before asking this question I analyse myself but couldn't find any better solution except the original builder pattern, accordingly I reach to the conclusion that Method cascade pattern is not purely alternative of Builder pattern.

[@friesmaker]

This makes me excited to write code again hahaha

[@giladbaruchian7522]

actually i rather use closeable than the trick you did there, and i set my compiler to show unclosed resources as errors so i dont forget or ignore

[@minjee9942]

@45:20 you could have used Supplier right? still makes the point he was trying to make

[@amol_]

[56:30] Unit testing is very important part of software so while writing unit test of sample class how can i mock Resource static function use?

[@AndiRadyKurniawan]

What editor is this?

[@kendallm]

He talks about his text editor setup on his website. www.agilelearner.com/presentation/5

[@corabora6644]

What is it about the fruit that they cant make TextMate for Windows ??

[@DarthCane]

When Venkat's talking about Strategy pattern, isn't that actually Template pattern? He's changing one step of the algorithm, not the entire algorithm. Can anyone explain the difference? I'm confused

[@thatoneuser8600]

Yeah, it looks like it's the template method pattern. Same order of steps, but the steps are different. Strategy pattern could have a completely different set of operations to fulfill its goal

[@dorbsz]

Anyone know the editor he uses?

[@vijayjayaram606]

U r GOD 🙏🏼🙏🏼🙏🏼🙏🏼🙏🏼

[@antimojv]

"In java 7 or early if you want to use a strategy pattern you often organize a corporate design meeting" lol ahahaahahahahah!

[@easonsolitud6098]

and if you really think about it

[@maitreeee]

8:20 made me laugh

[@dupindersingh1599]

What IDE he is using ?

[@itskumaresan]

Mac's TextMate

[@segwitchannel2042]

public static void send(Action blocker) { Mailer mailer = new Mailer(); blocker.Invoke(mailer); Console.WriteLine("sending.."); } --------> is this the equivalent code in C#?

[@kenichimori8533]

.deb script a port license.

[@ArisAlamanos]

Yeah!!! Let's all jump onto the functional programming bandwagon from a (now formerly) object oriented language! That'll be great! More mental model confusion will be great! Let's change programming languages and frameworks every six months I say! Let's completely change and mix-up features and paradigms all the time so that every generation of programmers is completely isolated from the previous and next ones. That's the way to go!

[@ivanvano13]

classic straw man argument

[@raman2072]

Wow! I thought you were intelligent and then you spoke! If you would have listened to his previous teachings, he clearly mentioned the folks at Java missed an opportunity to introduce Lambda 20 years ago when they introduced anonymous classes! Also seriously when did java ever change? Java is the ONLY language which build backward compatibility right from JDK 1.0 days. If you see python or Scala, or .NET, they are not that nice! They do not provide any backward compatibility at all and then your comment should actually be at the creators of Scala, python and .NET. and NOT at java at all. Also, Dr. Venkat made a great original comment -" if any language DOES NOT support backward compatibility, it is doomed. If a language supports it, it is doomed. Then the question is which way you wanna be doomed?"

[@Adventurevictoria]

That was really uncomfortable every time when he was overexpressing for a design pattern. We do have an issue with pattern and it gives us stress but does it mean this should not into the programmer world? ...for me, the reason we can tell Lambda is not just better but actually, renovation from previous java is because of where we've been through Yes, Design pattern. And Does Lambda will be the final destination of Java? I don't think so. Then Is any other engineer in the future should express as a silly thing for Lambda .. simply because of how the Lamda stress the engineer to memorise all the new API but not ready to test yet ?? How hard to debug? it's not ... its gonna be another stepping stone to improve as design pattern did. Please have reasonable respect to other's achievement before show off yourself mate.

[@gappergob6169]

No

[@0blackmilk0]

Man! Go Slow.

[@ColjaCarls]

Yes he is funny and yes, he is presenting deep and entertaining content but OH MY... this high pitched voice! Even lowering the volume cannot make it an easy listening. Me ears still hurt 🤯

[@mannysingh6618]

Venkat, you don't need to put on such a sharp accent, it does not sound natural. An Indian accent is fine.