Modern Java - Top Features of Java 9 to 17

In this episode we're going through the most interesting features added to the language in the last few years - between Java 9 released in 2017 and Java 17 released in September 2021.
00:00 Enhanced Switch
03:11 New instanceof
05:13 Type Inference (var)
06:50 Records
10:13 Text Blocks
11:32 Sealed Classes
16:06 of for Collections
17:16 Meaningful NullPointerException
Watch the next video about Java Stream API: • Java Stream API

[@kamilbrzezinski8218]

Watch the next video about Java Stream API: kzbin.info/www/bejne/q2qqgZuIn6eJsLc

[@jmwild1]

Great summary. I decided to jump from 8 to 17 and this is a great highlight reel of features I am happy to see (except maybe "var"). Another feature I love now is how easy it is to read and write text files using Files.readString() and Files.writeString().

[@kamilbrzezinski8218]

You're right, I should have covered it as well! Working with files in Java used to be a nightmare :)

[@leonardoamorimramos5656]

Great content Kamil! I really appreciate your highlights. Thank you!

[@SatheeshManimekalai]

Clarity in your content is really appreciable. You saved my day and thanks a bunch.

[@francksgenlecroyant]

Another man is subscribing to this channel! It's pretty awesome! Thank you for sharing!

[@kamilbrzezinski8218]

Thanks! I've been running a programming channel in Polish for more than three years and people like it, so I hope to give similar value to an English-speaking audience now. I'm glad that you subscribed, new videos are coming soon!

[@vladimirljubopytnov5193]

You ignore the most important feature, of the switch... it can be an expression and you can return a value. Why repeat the System.out.println() 4 times, when you can simply return the club and print it using one println call? Everyone seems to be obsessed about doing their side effects everywhere... Method is easier to test when you return a value.

[@fltfathin]

am JS pleb here, just to be clear does it work like this? T fn (args) { return switch(value){...}} ?

[@Kartoflaszman]

@@fltfathin yes, exactly. Expressions can be returned but statements (like if) cannot.

[@johndoedoejohn]

But this is for education purpose. System out is returning something as well, just to console, so it's still returns something 😄

[@vladimirljubopytnov5193]

@@johndoedoejohn System.out.println has a return type of void, that means it does not return anything. Side effect is not a return value.

[@DDVrns]

Great video! We need more Java videos like this, very easy to digest and helps with interviews for example (Just had a couple of interviews with new feature questions). Subbed and hoping to see more. Keep it up!

[@kamilbrzezinski8218]

Hi Daniel! It took me a while but I've just published a new video about Stream API: kzbin.info/www/bejne/q2qqgZuIn6eJsLc

[@pranavmahajan4190]

Recently switched to Jave 17. This is a great video. Thanks so much

[@kamilbrzezinski8218]

Thank you! I'm planning to make a video about Java 21 soon, there are some really interesting changes coming up! Yesterday I published a new video about Stream API: kzbin.info/www/bejne/q2qqgZuIn6eJsLc And I'm planning to publish new videos more often now:)

[@gennadiisitnikov1234]

Great! Simple explanation and demonstrative examples. Thanks a lot!

[@CaseStudy-bx4tl]

Very Helpful video for revising the concept in a short time thanks man!!

[@yamibakura7491]

Clear & concise, thankyou for making this video

[@ybendek]

wow man, awesome summary... I'm starting a new migration for a big project from java7... and now I need to know more about new features...thanks ;)

[@tanmayshukla4593]

That was really amazing man! You earned a like and subscribe!

[@kamilbrzezinski8218]

Thank you!

[@trannam4195]

Very imformative video. Thank you so much!

[@DrFrancis1686]

Awesome video, thanks a lot!

[@rohitgupta025]

Thank you for simple and easy presentation

[@ayushgupta8239]

Awesome content!! Sealed class concept is really interesting.

[@kamilbrzezinski8218]

It really is! I also recommend Venkat Subramaniam's talk on Sealed Classes: kzbin.info/www/bejne/jpzLZqaXaNudiqc

[@VaibhavPatil-rx7pc]

Excellently delivered

[@danieldias224]

Great video! I recently saw a meme praising Java 19 (I think), and was surprised to see what the fuss was all about. Not surprised to know that most of these features are already built in Kotlin.

[@eric-wubbolameijer9558]

As a concrete example where var is very handy: Spring! ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml"); Saves copy-pasting (or worse, retyping) the class name!

[@kamilbrzezinski8218]

And it makes the code much easier to read! Variable names are much more important than the class names and such long names like ClassPathXmlApplicationContext are nothing but noise.

[@mohamedsulaimaansheriff9787]

Great video! Subscribed❤❤

[@parkerbelholland1037]

Thanks and good comments too. Been using Java for years and haven't had the courage to jump from 8 yet. Still have nightmares jumping from 3 to 4 or 5.

[@faisalbehram7125]

Appreciated... Learn alot from this video thank you

[@haajiraaliyar78]

Useful Information on java 17.!!Excellent.

[@VibhuthaKumarage]

Very useful video. Thanks!

[@chethan93]

Awesome primer🤘🏽

Great video, thanks!

[@widearchshark3981]

This is such a great video. Haven't touched Java in years, and wanted to see what the differences were... Perfect ! Loving that NullPointerException message now. You know what it's like. As hard as you try, something somewhere doesn't get set. Then you're spending ages figuring out the specifics. This just gives you that little bit more detail to get you started. Really don't get the point of sealed classes/interfaces though. One useful thing I guess is it tells you which classes implement/extend it. But still, could come back to bite you in the ass I reckon! Thank you anyway. Really useful.

[@kamilbrzezinski8218]

I don't like the concept of sealed classes either. Venkat Subramaniam made an interesting video about it kzbin.info/www/bejne/jpzLZqaXaNudiqc, but still I just don't see myself using this feature in any future projects.

[@bronzekoala9141]

I love them, but I actually can't believe it took so long (C# too) to get them. It's such an obvious improvement and, from an outsiders perspective, low hanging fruit for improved efficiency when developing.

[@bronzekoala9141]

@@kamilbrzezinski8218 I don't like it as a concept either, but I read it improves performance because the compiler knows when and where to look for inheriting classes.

[@skagro1995]

Good video, you should add that records are inmutable , perfect for functional programming

[@svalyavasvalyava9867]

great video, thank you!!!

[@didimoner]

Helpful video, thank you!

[@kamilbrzezinski8218]

Thanks Dmitry!

[@nakulkumar9415]

Great video. I guess you forgot to mention that when creating collections using of method the collections created are immutable. Also for set there must be no duplicates.

[@temrimoose]

Great job bro , thanks from morocco ❤

[@gregmcpherson5671]

Thanks! I'll use a good deal of what you showed there. My Java writing is still shamefully very Java 8.

[@fc6827]

I appreciate the summary. While nothing quite as ground breaking as generics or function programming introduced in 7 and 8 (I think generics were 7?), really nice features if I can remember to use them!!

[@jibranjaved6165]

Java 5

[@nopalfi1409]

Great summary, i was kinda wonder about this because i started to learn java in JDK 17, but a few years ago i bought a book about java but it was 1.8 so i kinda wonder what feature i missed 😄

[@sheebaashraf]

Thanks a lot v quick and informative

[@vincentmax4571]

Very good information.

[@MrBrackets]

great video, thnks for sharing!

[@InderjeetSingh007]

Superb!

[@user-mc5xb3hc7m]

excellent summary

[@ashutosh887_]

Amazing Dude

[@user-qb3ck7cq3k]

Thank you!

[@rahulgoti3864]

Amazing Video :)

[@The_Original_Homeboy]

Good stuff. My project is currently stuck on Java 8 so it's interesting to see what changes have been made to the language.

[@kamilbrzezinski8218]

It's almost like a new language! :) And in September there will be Java 21 which also brings a lot of new features. I'm going to make a video about them soon! Now I only covered a new approach to the main method: kzbin.info/www/bejne/poWvl6qeeLSeh9U

[@shantilalprajapat4924]

Loved it 😍😍

[@ionthefightingaxe3835]

Simple and informative👍

[@kamilbrzezinski8218]

Good to hear, thanks!

[@MrAikien]

Thanks! 👌👍

[@jaskiratbamrah13]

I just save it in my GYM category , I will watch it later. I know this will help for sure.

[@obvioustruth]

Cześć Kamil!!! Pamietam Cię z FTIMS na Polibudzie Łódzkiej z 2013r :)

[@neilclay5835]

useful summary thanks

[@adyanto4043]

Null Pointer exception is the best frenemy of java.

[@amizan8653]

Super good video, thank you for posting! After seeing this... man I wish my company would adopt java 17 instead of continuing on with bloody Java 8.

[@kamilbrzezinski8218]

This is the grim reality, but Java 8 is the Windows XP of programming world ; ) Sometimes it feels like it'll be used forever.

[@challasaibhanuteja5314]

nice and informative

[@abdelkaderkaouane9682]

Thank you

[@Kamil-mw9jw]

Rapidly changing :D That was funny ;)

[@chax0208]

Im an apprentice that got taught by someone using Java 8. ur using 17 damn new features are good

[@kamilbrzezinski8218]

They are! Too bad so few companies are really using new versions of Java.

[@RonaldoArch]

great!

[@Unknown-hu4gf]

Hey, how do I get IntellJ IDEA to now hang and stutter when using it? Do I need a bigger CPU or something? I'm using a SSD and 32GB of RAM and my cpu is just a two core AMD, but it has a 3.4Ghz rating. And the thing just won't run smoothly! Are their configuration settings that I'm not using or something?

[@madhulikadubey]

Nice content

[@g0thqu054]

Thnx a lot for this nice content ! I have one question regarding records, could I use them for entities in spring with the annotation @entity?

[@kamilbrzezinski8218]

It took me a while to answer:) It's possible in Sprig Boot 3: dzone.com/articles/how-to-best-use-java-records-as-dtos-in-spring-boo

[@MrSdsc81]

Great video. Would love to have all this features sorted by Java version 😂 but it is cool anyway

[@Naglfar83]

Good explanation! Thank you much! Even though I don't see "var" as a top feature, but merely as something I have to criticize in future code reviews. ;-)

[@kamilbrzezinski8218]

One of the viewers came up with a concrete example where var can be used - long class names like ClassPathXmlApplicationContext. And I agree with this because usually a variable name is more important than a class name. So var is kind of a syntactic sugar making code a little bit cleaner and easier to read :) But I also agree that's not much and probably it'll be used extremely rarely ; )

[@jack_papel]

When you have to initialize a List you'll remember this comment 😅

[@02orochi]

U know Types are not always that relevant, right?

[@rishiraj2548]

Danke

[@vaishakhm3011]

Nice feature

[@zshn]

Does Record support meaningful NPE?

[@vorpal22]

(Great video, though... as someone who largely migrated from Java 1.8 to Kotlin, it's good to see this information presented concisely instead of having to dig it up all over the place.)

[@ananthakrishnankrishnan7287]

What’s the IntelliJ font you’re using?

[@mansoormohamedali122]

Plz which editor or ide are using.

[@ssswdon]

There use to be a flag that would allow NPE to generate a stack trace. I think they introduced in java8 and short cycling of NPE

[@Robin-od5cf]

What theme are you using for your IDE here?

[@kamilbrzezinski8218]

It took me a while to answer, but it's Nord: www.nordtheme.com/

when should you use records vs classes?

[@kamilbrzezinski8218]

When you want to have an immutable class that just holds data. It was present in Kotlin many years ago: kotlinlang.org/docs/data-classes.html And now Java introduced the same feature :)

[@aashishpundir3019]

please let me know if someone finds a better explanation... I don't even think it exists.. Awesome explanation.

[@kamilbrzezinski8218]

Thank you! I'm glad you liked it.

[@marcosdantasguimaraesfilho7747]

Amazing content! Such a shame you only have three videos out :(

[@JakNauczycSieProgramowania]

Hi Marcos! I'm going to start working on this channel! The new video should be out this week!

[@marcosdantasguimaraesfilho7747]

@@JakNauczycSieProgramowania Glad to hear that!

[@kamilbrzezinski8218]

@@marcosdantasguimaraesfilho7747 Hi Marcos! I've just published a new video: kzbin.info/www/bejne/q2qqgZuIn6eJsLc

[@Typelolpro]

what is the color scheme/theme you are using?

[@kamilbrzezinski8218]

It's Nord: www.nordtheme.com/

[@bb5242]

Groovy had the text blocks and var (def) at its inception, like in 2009 or whatever.

[@elgs1980]

You forgot to mention if Record covers hashCode, equals and toString or not? If not, there is little difference between using a class with all public fields.

[@kamilbrzezinski8218]

It covers all of them. And Record is immutable, so instead of writing/generating this (or using Lombok): public class Person { private final String name; private final String address; public Person(String name, String address) { this.name = name; this.address = address; } @Override public int hashCode() { return Objects.hash(name, address); } @Override public boolean equals(Object obj) { if (this == obj) { return true; } else if (!(obj instanceof Person)) { return false; } else { Person other = (Person) obj; return Objects.equals(name, other.name) && Objects.equals(address, other.address); } } @Override public String toString() { return "Person [name=" + name + ", address=" + address + "]"; } public String getName() { return name; } public String getAddress() { return address; } } you only need to write this: public record Person (String name, String address) {}

[@alessioantinoro5713]

If I remember well, the record toString(), equal() have a deafault implementation, so you are not forced to implement them

[@thibaulturien9103]

Wow great! If oracle keep this pace, by java 25 they will provide the same features as scala 2 with meaningful NPE on top of it! 😃

[@katarzynabrzezinska8546]

👍👍👍

[@morebowmore]

15:29 This feature violates OCP. Does Java really need it?

[@4L0N3xD]

5:14 so just like that all "adventages" of Python went away

[@CallidusLynx]

Nice presentation... new features have a little Kotlin touch, don't they?

[@somakkamos]

And yet java refuses to introduce tuples ... as are present in python.. its such a handy construct.. i guess record would be a way to achieve it..bt still u wud require a verbose atleast 1 liner to achieve it But awesome video... loved the depth yet simplicity

[@AB-ms7my]

5:44 typo. Should be "name3"

[@kamilbrzezinski8218]

You're right, thanks for catching this! It wouldn't have changed the behaviour though - if we use 'var' we need to initialize a variable in the same line.

[@kalyanchakravaty8445]

realtime projects please

[@rolfschierkowski8869]

You can also use umlauts in Java. So it's Müller not Muller.

[@JakNauczycSieProgramowania]

Yes, but since I don't use the German keyboard, I would need to manually copy the character from the Unicode table:)

[@imMavenGuy]

That's what she said - 8:23 😅

[@kamertonaudiophileplayer847]

But how to fall throw? You give also lot of examples using audio files. Maybe you know that Java can directly to stream music to DAC now? Just kidding, I know it can't.

[@kamilbrzezinski8218]

But why would you like to fall through? For me it always seemed like a bad design.

[@kamertonaudiophileplayer847]

@@kamilbrzezinski8218 Some time both cases are the same except a line of the code. So I do something like : case1, cases2: if case1 then doSomeSpecific(); doCommon(); How should it look when a good design?

[@LittleLily_]

@@kamertonaudiophileplayer847 Just move doCommon(); to after the switch. If you need the common to run for multiple cases but not all then you probably need to refactor something since at that point you're trying to be too clever for your own good and it'll just lead to confusing code.

[@kamertonaudiophileplayer847]

@@LittleLily_ If a language gives some feature, you always try to use it. Otherwise, it sounds fishy, the language contains some features in state - do not use them. Maybe it is time to select a different language?

[@friedec3622]

Say it with me, "public static void main (String[] args)"

[@typingcat]

For an old language like Java, trying to implement modern features without breaking the old code's compilability (it's a word, right?) does not seem to result in a good syntax. Why not just add some sort of compiler directive at the beginning of a file? So, if there is nothing, then compile it like Java 6 or something. If the file has something like /***Java 17*/ at the beginning, then compile it with a new syntax. This way, the Java language designers would have much more freedom to revive this relic language of the 1990's.

[@vladimirljubopytnov5193]

New syntax for JVM is usually signaled using a different extension like .kt or .sc (and different compiler is needed :D)

[@marcmil4064]

People sometimes copy and paste code snippets, making it easy to create incompatible code in the process if there was such a compiler directive and backwards incompatible syntactic changes.

[@clement1370]

Where is Mbappé ? 😌

[@kIllera911]

Hi Messi, Welcome to Manchester United

[@yohaneskustiadi9807]

So java 17 essentially almost like kotlin

[@JentaroYusong]

Mostly, just with a way more verbose syntax. 😂

[@VuLinhAssassin]

Problem is: most of these new features won't be adopted by "big tech" companies anytime soon, because... I think those corporations are the biggest obstacles to the development of java, as they almost have the final say over the technologies they will use, and how they plan to "upgrade" the infrastructure to accomodate modern Java. No matter how Java improves, they can just choose other modern languages for their projects.

[@unbekannter_Nutzer]

@5:45 you like to show, that `var name3;` can't be used, because it needs initialization on declaration, but you're trying to show it by assigning to `name` instead of `name3`. ;)

[@diegoramos27]

I’ve been a Java developer for over 10 years but after the serious Logj4 vulnerability it makes me wonder if this still still the correct path…

[@nathandunkley4749]

Switch to Rust. That's the language of the future

[@02orochi]

Go for groovy, its still java but in an Arguably better language

[@jimmykochi6442]

Kotlin is also great, only jetbrains tooling available tho

[@marcmil4064]

@@jimmykochi6442 Kotlin code is essentially equivalent to Java code in terms of vulnerabilities.

[@mayankmittal1344]

It would have been a better video if you gone through the changes in the chronological order.

[@kamilbrzezinski8218]

Might be a topic for another video :)

[@guidow9616]

or just switch to Scala or Kotlin

[@Videshideshbhakt]

Java seems to Kotlin now!

[@kamilbrzezinski8218]

For sure they took a lot of inspiration from Kotlin and that's good!

[@vorpal22]

At 8:00, why are you inserting getters if the fields are declared final? What's the point? Just make the variables public. (Not to say that records aren't a huge improvement, like Kotlin data classes, but still... I'm not even sure why records can't make their variables public and need to add accessors.)

[@egozMaster]

do you know OOP rules ?

[@vorpal22]

@@egozMaster Yes, I do, and I can see why you might want to make them methods if you decide to change their underlying representation at some point, but for something this simple, you will almost certainly not. Look at Java Swing (and other Java APIs, but Swing is where it is most prevalent from what I've seen), for example: it defines a huge number of final constants with int values (not enums) to be passed to things like borders, alignments, etc. Following strict OOP rules is so late 1990s / early 2000s. Most of the organizations I know and have worked with now use a combination of immutable objects (which are basically equivalent to records) and functional programming instead of long-winded pointless strict OOP principles. I mean, if you want to aim for verbosity and redundancy, knock yourself out, but a final field that stores a primitive type or an abstract interface is just as good as a getter. Do a basic google search and you'll see that pointless getters have fallen out of fashion. There's no need to aim for strict purity unless you're a pedant.