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Thanks so much!

You’re talking about Java’s remote method invocation, right? I’m a little curious on what the use case is :) I’ve done a lot more with CORBA, but I can brush up on RMI and make a video if you’d like!

@@willtollefson the use case is a college class. This time it's a course about distributed systems. Your socketing videos helped a bunch last semester, you make quality content.

Got it - that makes sense. I’ll try to post something about Java RMI in the next few weeks. Good luck with classes this semester!

Thank you! Glad you liked it

Thanks for the comment - I can try to slow down a bit during the parts at the end where it’s a lot easier to jump around the code more. I also have the full code posted if that helps

You bet. Happy to help!

Glad to hear it helped!

Updated the video description with a link to the code on GitHub. Enjoy!

Thanks! In the meantime I went through the pain of copying. I slightly adapted it, to use UnixSockets. I'll probably push it to GitHub one of these days.

My pleasure!

Appreciate the feedback. In later videos I haven’t been doing the music. Be sure to check some of those videos out!

Thanks, I’m glad you liked it!

It’s on my todo list to get the code from these videos on GitHub and I haven’t gotten to it yet - sorry about that!

github.com/Will-Tollefson/yt-java/tree/master/2024/Factory%20Pattern I also updated the video description. Enjoy!

selector.select() is a blocking call. I assume when you say that the process stops that you're saying the program hangs at that call rather than the program stopping such as throwing an exception or Java crashing entirely. That call is a blocking call because the selector is waiting for an operation on one of its selected keys to fire. If the selector has a key registered and that key triggers an event, you should move on from that select() method and into more logic in your code. For example, the code in the video moves on initially when a socket connection gets established and the OS is ready to accept the connection.

It might be good to take out some of the complexity to verify your setup. Write a simple program and add breakpoints to make sure in the nominal case you can see them. Once you have that working, slowly go back to your problem at hand and confirm the setup is equivalent, you’re hitting the code you think you are, and the breakpoint is enabled and not conditional. Good luck!

Happy to do so! PORT_NUMBER is referring to the source port number for the server specifically. The reason both the client and server need this is because the server uses it to bind the server socket and the client uses it as a destination port when it talks to the server. The port that is printed out in the output window is the client's source port (aka the server destination port), which by default is determined by the OS when the client creates the TCP socket.

You’re welcome!

Great question! Short answer: yes it could help depending on the context As far as I know Processing ships with its own Java version, so you’d need to make sure it’s using Java 21 or later. Also it’s been a while since I’ve looked at the n body problem, but if your equations can provide sufficiently discrete computations that don’t require too many hand offs, then yes scaling the application to more bodies can be more efficiently done with virtual threads. Hope this helps!

@@willtollefson thanks, I'll give it a try. Only one way to find out!

Thanks so much. I’ll keep posting Java content when I can!

You’re welcome!

Thanks! I was a little later making this video than I wanted to be, but here I am!

Thank you!

Glad you liked it! I thought this one was fun to make 🙂

Happy to help!

Glad to hear the video was helpful! Factory and its variants are definitely some of the key OOP patterns. A few other good ones I see regularly are state, observer, decorator, and strategy. Good luck!

You’re welcome. Glad to hear that it was helpful!

Thanks!

Thanks for the question! The short answer is that the stack traces in the thread dump will usually tell you enough for a simpler example like this, but I do hear your point about more advanced debugging. In this particular example the trace tells you the line number its blocking on waiting for monitor entry and it tells which thread its waiting on. I've thought about making a video (or a series) on different debugging techniques with threading issues being a top contender. Is that something you'd like to see?

@@willtollefson Yes; I would love a series about that. I have been studying computer science for two years now, but my textbook and classes never talked about the debugger. It's actually really embarrassing that I know nothing really about it😂😂

@audiomac sounds good - I totally get it and I've heard that from a lot of folks. It seems like teaching debugging isn't always a priority which is odd to me since that's a decent portion of what devs do in industry. I'll see about putting out some more debugging videos in the future. Thanks!

There are parts that are harder than others, yes. I found it helpful to take a higher level look at the stream API before taking a deeper dive into a component of it. If there’s anything I can help explain better, feel free to reply on this thread!

My pleasure!

Glad it was helpful!

Sure! Anything specifically you’d like to see?

Thanks for the question! I glossed over that part in the video. The reason it’s doing that is because there needs to be a way to look at the status of the 1000 requests asynchronously and the way I implemented it was a status thread that starts executing after you construct the Server object. It could have instead been a getter that gets called periodically after the requests start submitting, but with the code as written if it weren’t done in a separate thread, the executor block would never be hit because the main class would have been blocked after Server constructor if that private method was called from in the constructor with the same thread. Hope this helps!

A while back I was a big eclipse user. The last 5 years or so IntelliJ has been my go to though. Hope you liked the video!

Do you want to know about how garbage collection works in Java in general, or specifically how it would pertain to something like a template expression?

Thanks!

Threading issues and deadlocks can be some really interesting bugs to solve, which is why those thread dumps can be really useful!

Good catch - its supposed to be (101 + 102 + ...). I must have had the number "1000" in my head. Thanks for noting that!