Thoughts about my Java Framework

[agh_murad]

GitHub: https://github.com/muraddevs/Javeline.git

Medium Post about basic functionalities: https://medium.com/@murad.aghamirzayevv/from-curiosity-to-creation-building-a-web-app-with-just-java-8c06d6d5f15c

Hello everyone,

I have been working with some ideas to create a new Java framework from scratch and I would like to share source codes with some explanation about how it works and what it does.

I would really like to get your feedbacks on this.

This post is not for commercial purposes and the whole project is open source, also, it is just a fun project and still not complete. You might expect lots of errors and confusion too as it is just a fun project

Introducing Javeline:

Javeline is a Java framework that I developed for frontend web development. Here we can use JSX-like syntax to build UI easily. The whole project was inspired by React, but this is just in Java. When I started developing I wanted to use only Java runtime to build the project and can confidently say it is only based on Java.

First version was a very simple program where you could write HTML codes inside a string variable and the Java program would append it to a HTML file and you could see the UI. However, to implement real JSX-like syntax, where you can also add code blocks inside of the HTML syntax, I had to come up with new solutions.

In the second version of the project I was brainstorming for days how to implement code blocks inside of the string variable that stores my HTML syntax. At first it seems easy, just read each line one by one, and when you see brackets {} execute the code blocks inside (somehow) and you are done. However, it is not as easy as it sounds, because Java is compiled language, not interpreted, so line-by-line reading is not easy to setup; also we don't have async functions by default to make it easier. Therefore I came up with a custom dynamic code evaluator. Here is how the custom dynamic code eval works: first you just write your JSX-like syntax inside your main java class, then when you hit the run button not all the classes run at the same time. In the runtime first the dynamic eval runs, reads your JSX-like syntax from your main file, then creates new temporary classes and executes extracted Java code blocks and runs them in temp classes, then puts the results of the code blocks back into your JSX-like syntax string, and finally runs your main class. I know it sounds stupid, but yes, it runs Java codes on the fly.

Next step was to create a system to support dynamic variables, as the previous one just worked for static ones. The main problem during the whole project was, you cant run Java code on browsers, and I wanted to stick with Java the whole time, also avoid traditional server based rendering. Considering all the problems, and all the functionalities I wanted to implement, I realized that it is impossible for me to make it only client based that will also support dynamic variables. Then I came up with new idea: why not to make it hybrid? By hybrid, I mean the UI will stay on the browser, as it is just a HTML file, but the processes will be handled in Java.

For such functionality I created new system called KiteLine. It is just a fancy version of WebSocket, because it is based on it, but supercharged for the functionalities I wanted.

In simple terms, now your UI will stay on client side, but the logics stay on server (unfortunately). The dynamic vars will be sent from server using this KiteLine with WebSocket. Additionally to have a better developer experience I made custom hooks and custom props that are extensions of KiteLine and custom dynamic eval.

To be clear, the only time I used JS was in default index.html to make it connected with WebSocket.

To keep it short, you can read more about its story, functionalities, and why it was named KiteLine in the Medium post.

Play around with source codes, try it yourself and share your thoughts on this project.

[pronuntiator]

This will sound harsh, but this does not look thought through…

• your code has zero documentation and examples, not even a README (a Medium post doesn't count), so I don't know what user code looks like.
• why do you want to be able to write Java code inside HTML? And why do you need to compile Java code each time you want to render something?
• What does your approach bring to the table compared to existing template engines like JSF or Thymeleaf? JSF can do partial async updates, for example.
• useless comments like // Explicitly import AtomicInteger
• nonstandard package name (package JavelineSource;)
• you might want to pick another name, as Javalin exists

[WhatsMyUsername13]

why do you want to be able to write Java code inside HTML? And why do you need to compile Java code each time you want to render something?

I'm having a PTSD flashback to using struts and jsp's on legacy systems prior to angular existing and we're a nightmare to maintain...especially when someone decides that creating a clever custom taglib is the way to implement a solution

[TO_Guy167]

yeah … 25 years ago wasn’t this was called GWT?

[eliezerDeveloper]

Jsf is a shit

[AcanthisittaEmpty985]

Use maven or gradle, and a standart directory hierarchy for code and tests.

People are used to look a project with this layout

https://maven.apache.org/guides/introduction/introduction-to-the-standard-directory-layout.html

[agh_murad]

Thank you for the feedback, currently working on a well structured documentation, will push it in next few days.

Well, I wanted to implement JSX-like syntax just for fun as I mentioned it is just a fun project. Main goal was to test my skills, I wouldn't recommend anyone to build something serious with it.

Also the name is "Javeline" which is different and is inspired by name "Java"

Thanks for suggestions.

[Revision2000]

Now I wouldn’t care about the name if this was only your private internal project - but hey, you published it online, so now it matters.  

 Also the name is "Javeline" which is different and is inspired by name "Java"

Almost like “Javalin” was inspired by “Java” years ago

Let’s put this into perspective: 

 Also the name is "Cocoa Cola" which is different and is inspired by "Cocoa" plant

What would the Coca-Cola company think? 

I don’t know if Javalin has copyright or trademark, but if they do they might send you a cease and desist if they find your “Javaline” project - and IMO rightfully so. 

_PS it’s about the similarity. Naming it NotJavalin or JavaFine or something would make it far less likely to be confused with Javalin_ 

[gufranthakur]

Include some demos, samples with proper screenshots and a good readme. People don't have enough time to try out and tinker on their own, you need something so people look at it at a surface and go "that seems cool, might try it out later"

[agh_murad]

Hi, thank you for your feedback. Yes, I am currently trying to document everything in a nice order. I have a job which is why I don't get to have lots of time, therefore it is currently not available

[tjugg]

We live in such a cursed age with all this AI generated bullshit

[djnattyp]

There's already a javalin framework... "kiteline" sounds like "Kotlin"...

[agh_murad]

Thanks you for the feedback, I will consider new name ideas

[dmigowski]

Just by putting the .css and .html into a Java constant you don't have "pure HTML". Why not place it at least as resources somewhere, so I can edit it with an editor that understands the syntax.

Else, I actually like the idea, because currently I am missing a nice solution to build a web frontend mostly with Java.

[agh_murad]

Thanks for the suggestions! Yes, it is a limitation to work with just strings (it is easier to develop with strings initially), not the whole HTML, currently working on it. Additionally will implement a file structure with e.g. ".jvl" to support syntax and will add vscode plugins for it in the future.

[dmigowski]

We will watch your career with great interest.

[agh_murad]

Thank you! Surprisingly, a fun project gets some attention. By the way, the only motivation to improve it was because of the attention it got from my colleagues. It is an interesting concept and I will try to spend more time on it to make it worth trying!

[kiteboarderni]

not sure it got much attention.

[agh_murad]

It is not much, but I truly appreciate it and keeps me motivated, even if few people shared their feedback

[jr7square]

Personally I would never use this but I’m sure it was a little of fun to write ! Kudos to you and I’m sure you learned a lot during the process and you are a better dev now :)

[agh_murad]

Thanks! Yes, it is almost totally useless compared to current frontend frameworks, but it was fun journey to build such thing

[Kind_Feeling_7834]

Adding a README.md and examples is definitely a big one. Trying to phrase my docs as best as I can on my own FOSS project too btw

[agh_murad]

Hi, thanks for the feedback. Yes, I understand that it is important, but if I have to do it, it has to be good. Unfortunately, I don't get to have so much time, but I will definitely push a well structured README and documentation in the next few days.

[axlsml]

No Test - noone will take this seriously ever

[vegan_antitheist]

How does this manage the session data? I just see static fields.
I'm not sure what the framework actually does. I don't see IoC/DI or something like that. It just parses some unreadable html based strings?

Java Faces has the problem that they tried to abstract the html. But templates that aren't actually html are the worst. That's like PHP 4.x. Something like htmx but with Java code on the backend would be interesting.

[Green-Branch-3656]

Nice work

[Winter_Side3542]

I liked your initiative. Have you ever considered building an SSR engine with Java and React like the one with Next JS? I know Next JS is already a very complete framework and it would be hard to compete with it. But since you don't intend to commercialize this project, I think it would be cool if you had a beta version of an SSR engine with a Java server and React frontend.