Hi John, loving your videos. I am a senior Java Developer too and your explanations help me reaffirm my understanding and most of the time declutter my misunderstanding. You are excellent at what you do. Request you to consider a course on Design Patterns. Ty!
Thanks! I'm always nervous I might be a bit too silly with stuff like this video has, but putting it in makes me happy. So I hope others enjoy it as well.
@@CodingWithJohn The vids are explained in a very ez and understanding manner. It's just your style. Silly or not some people will like it, others won't. Don't worry about people's opinions. Love the vids!
Thank you, John. I'm still in school and constantly feel like I know nothing, but watching your videos and genuinely learning something makes me feel slightly better lol. Thank you for what you do.
I had some questions about garbage collection and multithreading for java in an interview. This video opened my mind about java. I was thinking like, Oh, i know java. But there is much to learn i guess. Thanks a lot!
If you want a broad strategy on how to generally write more performant code in Java, that can be summed up into a single sentence: "Use Javas built-in tools as much as possible, and make sure you research that its intended use matches what you're doing with it". The problem with a question so broad is that every instance of 'optimizing performance' is a unique type of problem and would require just as many videos. If you look at Johns catalogue you will find many videos that touch on individual problems and the considerations when optimizing them. But he doesn't have infinite videos. Say you're trying to optimize a custom sort on an array of json objects, are you trying to optimize for execution speed or memory management? Both are different types of performance. Both will have different considerations and may be done entirely differently. Optimizing a custom sort of a different type of object might also have its own set of approaches for either speed or memory. But back to my first point, if there is a built-in Java object type or method meant to do the thing you are trying to do, it is a more mature solution than your custom sorter would be. It will likely be reasonably efficient with both speed and memory, and will catch more edge-cases and have more informative errors for them than a custom solution.
Don't use Java for performance critical code. Outside of that, it's about the same as for every other managed language: make use of the library and write simple code. Performance is generally good enough and it prevents you from shooting yourself in the foot. If that's not good enough, really, don't use the JVM.
I often heard garbage collection but hadn't understood it's mechanism at all. It doesn't affect my Java coding much to learn fundamental concept, But I think it will help me code properly. Your videos very easy and helpful to understand fundamental concept about programming for beginner. many thanks!
I was just recommended this video about Java Garbage Collection, and I don't even use Java, but let me give you some advice: Learn the fundamentals, they may not make much sense for you now, but boy they will save your ass down the line
John, love your content, i'm primarily self taught and want to turn this into a career after my current obligations. I had some ideas i'd love to see from you, one being for people like myself, of which there are many, is a video detailing many of things that get overlooked when self taught, for example, how array lists and linked list differ performance wise (This isn't the best example but hopefully you get the idea), there are lots of things overlooked when getting from point A to point B being self taught and it could be really useful. A more simple idea i would love to see is a video teaching use about bitwise operators and how they are used and work, or maybe a video talking more about bigger picture things like using version control with git and team environments, love the content, keep it up!!!
I am being studying and work with Java very long time , but Only John's video I love the most! Nice video as always. Is that possiable you can talk about Comparator ?
a part of gc that i find interesting is WeakReference and SoftReference, which indicate to the gc that although this object is referenced it can still be collected now or whenever you really need to free the space
Once upon a time, I had some colleagues who believed that setting a variable to null somehow "helped" the garbage collector. It was difficult to convince them that it was all superstition, and that no, it wasn't doing anything. Sometimes, the smartest minds are also the dumbest.
When GC recalls memory, does it need to make sure it's not dirty (written before)? I'm confused by GC and demand page management in virtual memory. thanks!
Nice, your explanation is awesome, genuinely never understood what garbage collection is. Idk even know what "in memory" really means and where that memory is💀 Is there a way to see all these garbage collection processes in real time whilst programming?
many thanks for your tutorial clips, but as a beginner I don't know what is the first and what is the last clip, I mean it is better you put a number for each clip so everyone can watch them in order
plz answer me. i just finished java course with oop and data structures and when i go back to old subjects i feel that i forget it and i learn it again to memories it so plz tell what should i do. spend time on leetcode or learn spring boot and build projects because i want to be java backend developer
Hi John. I love your vids. I even subscribed to your course which has helped me immensely. I have a request.. Can you maybe do videos on JavaFX too? Thank you so much ! Meow!
So if I just created an object but never assigned that object to a variable, that means to a reference in memory, that object would get garbage collected basically immediately?
Yep, it would at least be eligible! If your whole line of code was just: new Cat(); It's immediately unreachable. It wouldn't necessarily go away immediately because GC works in batches, but in the next round of collection it would definitely be gone.
Thank you for the video! Could you create another one focusing on RestTemplate and WebClient? I'm aware RestTemplate is being phased out, but could you explain the reasons behind it?
You can suggest that the garbage collector run by calling System.gc();, but this doesn't guarantee it will actually do it. I've never had to do this in my entire career, I've always been able to rely on the garbage collector to do its job without any management.
With so much gratitude I want to appreciate papa-dora on TH-cam for showing up in my life at the right time. I have been down with HSV for almost a year, coming across papa dora TH-cam channel and purchasing his medication was the best news of my life. Thank you doctor
Not at the moment, the course is more geared toward beginners. All lessons that are included are shown on the course page so anyone can make sure it's what they're looking for before moving forward.
Hey John! Great course! i was wondering if you are planing on making a more advance course aswell, like a part 2 after you finish the beginner friendly one? @@CodingWithJohn cheers!
Hello John, hello everyone; please I’m a computer science student who really wants to go into programming but I’ve still not figure out what aspect to go into; is Java a good place to start, can we create software with java? Pls I need y’all contributions and advice Thank you Btw, I wish to be a software engineer
Alex lee is another youtuber who taught me many things and bro code as well but I cannot see the stupid front end languages surge on the market why is that????
Devil's advocate here: If we still have to set `ptr = null;` to make it (eventually) free the memory, from the programmer's perspective how is that anyhing more convenient than writing `free(ptr);` or `delete ptr;` as we do in C/C++ ? What problem does it solve? How is this anything different from manual memory management, except for introducing more runtime overhead?
My friend John why don't you make a video to discuss the racism that Back End Developers receive from the the stupid Front Ends because many like me are declined day by day. I have been declined as well but I don't care about that because to make ends meet I started youtube but anyways Front End dev's thinking is annoying from personal XP
Hi John, loving your videos. I am a senior Java Developer too and your explanations help me reaffirm my understanding and most of the time declutter my misunderstanding.
You are excellent at what you do. Request you to consider a course on Design Patterns. Ty!
umm I would gladly PAY for design patter course from John with concrete, commercial examples (instead of cats and dogs in that case) 😅
Your ability to effectively simplify complex topics with the exact right amount of information is impressive. Thank you for sharing your insight!
Besides the excellent coding tutorial, I come here to John's uplifting presence and his joyful smile.❤
Thanks! I'm always nervous I might be a bit too silly with stuff like this video has, but putting it in makes me happy. So I hope others enjoy it as well.
@@CodingWithJohn The vids are explained in a very ez and understanding manner. It's just your style. Silly or not some people will like it, others won't. Don't worry about people's opinions. Love the vids!
The only thing better than this explanation was the video's intro. Great work as always man! I'm a fan! Greetings from Mexico!
Thank you, John. I'm still in school and constantly feel like I know nothing, but watching your videos and genuinely learning something makes me feel slightly better lol. Thank you for what you do.
tbh you'll always feel like you know nothing in cs, imposter syndrome is real.
@@gagangowda9928 I'm feeling that more and more lol.
I had some questions about garbage collection and multithreading for java in an interview. This video opened my mind about java. I was thinking like, Oh, i know java. But there is much to learn i guess. Thanks a lot!
I just had the same experience, I felt embarrased in that interview.
Make a video on how to optimize java code's performance!
This is such a generic request, "optimizing Java code" is far too broad of a subject to address
@@guinea_horn if you can direct me to some resources it would be helpful.
If you want a broad strategy on how to generally write more performant code in Java, that can be summed up into a single sentence: "Use Javas built-in tools as much as possible, and make sure you research that its intended use matches what you're doing with it". The problem with a question so broad is that every instance of 'optimizing performance' is a unique type of problem and would require just as many videos. If you look at Johns catalogue you will find many videos that touch on individual problems and the considerations when optimizing them. But he doesn't have infinite videos.
Say you're trying to optimize a custom sort on an array of json objects, are you trying to optimize for execution speed or memory management? Both are different types of performance. Both will have different considerations and may be done entirely differently. Optimizing a custom sort of a different type of object might also have its own set of approaches for either speed or memory. But back to my first point, if there is a built-in Java object type or method meant to do the thing you are trying to do, it is a more mature solution than your custom sorter would be. It will likely be reasonably efficient with both speed and memory, and will catch more edge-cases and have more informative errors for them than a custom solution.
@@ericpenrose3649 Thanks man!
Don't use Java for performance critical code. Outside of that, it's about the same as for every other managed language: make use of the library and write simple code. Performance is generally good enough and it prevents you from shooting yourself in the foot. If that's not good enough, really, don't use the JVM.
Kindly do dynamic programming , you make the complicated so simple .much love from Kenya
John, you're amazing! Was just reading an article on GC and I was really confused, I'm so glad I found this video. Thank you!!!
I often heard garbage collection but hadn't understood it's mechanism at all. It doesn't affect my Java coding much to learn fundamental concept, But I think it will help me code properly. Your videos very easy and helpful to understand fundamental concept about programming for beginner. many thanks!
I was just recommended this video about Java Garbage Collection, and I don't even use Java, but let me give you some advice: Learn the fundamentals, they may not make much sense for you now, but boy they will save your ass down the line
No bs, straight to the point showing us how its done.
Your videos are always a must for me
Great tutorial John, thank you for the video ! Please keep up with such more complex concepts, you are a great teacher.
Good to see you back, pal! Never thought about GC as you said, but this was a really good understandable explanation of getting into it
John, love your content, i'm primarily self taught and want to turn this into a career after my current obligations. I had some ideas i'd love to see from you, one being for people like myself, of which there are many, is a video detailing many of things that get overlooked when self taught, for example, how array lists and linked list differ performance wise (This isn't the best example but hopefully you get the idea), there are lots of things overlooked when getting from point A to point B being self taught and it could be really useful. A more simple idea i would love to see is a video teaching use about bitwise operators and how they are used and work, or maybe a video talking more about bigger picture things like using version control with git and team environments, love the content, keep it up!!!
I am being studying and work with Java very long time , but Only John's video I love the most! Nice video as always. Is that possiable you can talk about Comparator ?
Man I really wish you taught other languages (like C), your explanations are some of the clearest I've ever found on the net!
I really appreciate your effort with these videos
Hi John, really love the video.
Good to see you again.
You're the best java teacher i never have
thank you very much, very helpful video
i despise java but your channel is still very very helpful, thank you :)
a part of gc that i find interesting is WeakReference and SoftReference, which indicate to the gc that although this object is referenced it can still be collected now or whenever you really need to free the space
Great video, complex topics require simple explanation, keep going :)
Well in the last John is just mimicking the java garbage collector when he sees any new object without any reference
GET IT
@@CodingWithJohn Please, don't remove me from OldGen club, I still have a lot of references.
Hello John :) can you please make a video about spring boot? It’s so useful but so confusing still for me :/
Love those first 2 seconds 😂 ❤
Once upon a time, I had some colleagues who believed that setting a variable to null somehow "helped" the garbage collector. It was difficult to convince them that it was all superstition, and that no, it wasn't doing anything.
Sometimes, the smartest minds are also the dumbest.
Usually it's not necessary if the variable is scoped correctly, but it can technically do something!
Nicely done - thanks for sharing.
Thank you John, I was looking for a content regarding GC. I owe you a coffee.
Really a very helpful video and the way of explanation is awesome ❤❤❤❤❤❤❤
bonus part is awesome :D
8:33 Where's the other video?
Please, more on better memory management!
Hey John! I would love to see a video about Ressource bundle :)
Thank you for making this video.
we need a tutorial about tokners and input/output data please mighty John we rely on you
John's back!! 😃
When GC recalls memory, does it need to make sure it's not dirty (written before)? I'm confused by GC and demand page management in virtual memory. thanks!
Hi Jhon, I like the way you explain things. Do you know how to explain microservices in java?
I love for your videos. where are you? we miss you!. can you make a video about stream and how to use it to filter or map ? thank you
Nice, your explanation is awesome, genuinely never understood what garbage collection is. Idk even know what "in memory" really means and where that memory is💀
Is there a way to see all these garbage collection processes in real time whilst programming?
"In memory" meaning data stored in a computers RAM and sometimes ROM. When computers run out of memory it creates an overflow exception.
@@itzdm0r3 cool, I'll check that further out
many thanks for your tutorial clips, but as a beginner I don't know what is the first and what is the last clip, I mean it is better you put a number for each clip so everyone can watch them in order
Ideas for new chapters: Future class, jars compilation, working with configurations, Spring
Amazing video ❤
Happy New year 🎉🎉🎉🎉
plz answer me. i just finished java course with oop and data structures and when i go back to old subjects i feel that i forget it and i learn it again to memories it so plz tell what should i do. spend time on leetcode or learn spring boot and build projects because i want to be java backend developer
Hi John, do you have videos about jar, war and ear files?
John more leetcode explanations please!
Great video 😁
Does your java course go over recursive methods? Thanks
simple and clean !!
Hi John. I love your vids. I even subscribed to your course which has helped me immensely. I have a request.. Can you maybe do videos on JavaFX too? Thank you so much ! Meow!
Can you start a playlist on Spring/ Spring Boot... Our guest lecturer is running on a jet RN and ofcourse we can't catch up 🙃
Would you be able to create videos for other framework GCs as well. For example node.js
Heyyyy,look who's back
So if I just created an object but never assigned that object to a variable, that means to a reference in memory, that object would get garbage collected basically immediately?
Yep, it would at least be eligible! If your whole line of code was just:
new Cat();
It's immediately unreachable. It wouldn't necessarily go away immediately because GC works in batches, but in the next round of collection it would definitely be gone.
Thanks John for the wonderful explanation. Cud u pls talk about System.gc() and finalize() methods as well in the next part?
John my man gonna get me out of poverty 🙏
Could you recommend books for java developers
Thank you for the video! Could you create another one focusing on RestTemplate and WebClient? I'm aware RestTemplate is being phased out, but could you explain the reasons behind it?
Is there a way to free up the space manually if I know that the object wont be used anymore?
You can suggest that the garbage collector run by calling System.gc();, but this doesn't guarantee it will actually do it. I've never had to do this in my entire career, I've always been able to rely on the garbage collector to do its job without any management.
During this process when finilize method is called ?
In older languages you had to do memory management manually. These high level languages are great imo. 😂
The biggest reason I lean on Java/C# over C++ lol
Thanks mate. By the way, how is your junior dev going? 😊
Also my dumb brain got it. thank you so much
lol I loved the title of this video
We want bald John back! We want bald John back! We want bald John back! We want bald John back!!!!
Great content as always.
Make video about SLL and DLL
Do an example of this topic please.
Thank bro, Keep make new videos
that is amazing content :)
With so much gratitude I want to appreciate papa-dora on TH-cam for showing up in my life at the right time. I have been down with HSV for almost a year, coming across papa dora TH-cam channel and purchasing his medication was the best news of my life. Thank you doctor
Are those ridiculously complicated Garbage Collection details covered in your complete Java course?
Not at the moment, the course is more geared toward beginners. All lessons that are included are shown on the course page so anyone can make sure it's what they're looking for before moving forward.
@@CodingWithJohn Understood, thanks John
Hey John! Great course! i was wondering if you are planing on making a more advance course aswell, like a part 2 after you finish the beginner friendly one? @@CodingWithJohn cheers!
Greetings dude ✌️
So, the JGC is essentially the Davy Jones. Collecting lost souls.
This video could've been alot more complete if it included a short explanation of how does the GC figure out that an object is not referenced anymore.
Hello John, hello everyone; please I’m a computer science student who really wants to go into programming but I’ve still not figure out what aspect to go into; is Java a good place to start, can we create software with java? Pls I need y’all contributions and advice
Thank you
Btw, I wish to be a software engineer
Yes Java is a very good language, but you should always start your programming journey with C as it builds basic programming logic
Why not just delete stuff as soon as it goes out of scope? I don't understand the need for the extra complexity.
That jumpscare :{_-_-_
Funny ending 😂
enjoyed laerning
Alex lee is another youtuber who taught me many things and bro code as well but I cannot see the stupid front end languages surge on the market why is that????
So we're not dissing on Java's Collection framework then?
John you legend, when will you finally go for President?
Devil's advocate here: If we still have to set `ptr = null;` to make it (eventually) free the memory, from the programmer's perspective how is that anyhing more convenient than writing `free(ptr);` or `delete ptr;` as we do in C/C++ ? What problem does it solve? How is this anything different from manual memory management, except for introducing more runtime overhead?
I think the main reason is that programmers don't want to write those lines of code.
backgroud more like - I am a lead guitarist.
👍👍👍👍
Lovely
üstad nasıl... anlat bize de bu işin sırrı ne ?
what is your secret ?
My friend John why don't you make a video to discuss the racism that Back End Developers receive from the the stupid Front Ends because many like me are declined day by day.
I have been declined as well but I don't care about that because to make ends meet I started youtube but anyways Front End dev's thinking is annoying from personal XP
Brr I hate Java brrr.. but i love JavaScript.
Do you have group on discord ?