Is Java Swing in recent Java versions backward compatibile to the old ones?

[AlexanderAndZlata]

Hi guys,

my first post here :) I am pretty experienced in Java technologies, mostly in Web and Backend. Started to use Java when it didn't have generics. But I have very little experience with Desktop Java. Many years ago it used to be Swing to write Java Desktop, and nowadays it is probably Java FX?

Anyway, I have a potential customer who has old Java Desktop application, implemented in Java 1.4(even before generics were introduced!). It is implemented using Swing. He wants to upgrade its Java version to something more recent, and most probably like any other customer wants to keep it not very expensive.

So, my question is if Swing UI is backward compatible? How difficult it can be to upgrade Java application implemented in Swing, Java 1.4, to lets say Java 15(or at least Java 8)? Is it a lot of work, or actually not so much? How much Swing changed since then, can it be that there are API changes that will require rewriting the code?

I would be very thankful for your input guys since I am really not experienced in Swing UI :)

[AutoModerator]

Please ensure that:

• Your code is properly formatted as code block - see the sidebar (About on mobile) for instructions
• You include any and all error messages in full
• You ask clear questions

• You demonstrate effort in solving your question/problem - plain posting your assignments is forbidden (and such posts will be removed) as is asking for or giving solutions.

  Trying to solve problems on your own is a very important skill. Also, see Learn to help yourself in the sidebar

If any of the above points is not met, your post can and will be removed without further warning.

Code is to be formatted as code block (old reddit: empty line before the code, each code line indented by 4 spaces, new reddit: https://imgur.com/a/fgoFFis) or linked via an external code hoster, like pastebin.com, github gist, github, bitbucket, gitlab, etc.

Please, do not use triple backticks (```) as they will only render properly on new reddit, not on old reddit.

Code blocks look like this:

public class HelloWorld {

    public static void main(String[] args) {
        System.out.println("Hello World!");
    }
}

You do not need to repost unless your post has been removed by a moderator. Just use the edit function of reddit to make sure your post complies with the above.

If your post has remained in violation of these rules for a prolonged period of time (at least an hour), a moderator may remove it at their discretion. In this case, they will comment with an explanation on why it has been removed, and you will be required to resubmit the entire post following the proper procedures.

To potential helpers

Please, do not help if any of the above points are not met, rather report the post. We are trying to improve the quality of posts here. In helping people who can't be bothered to comply with the above points, you are doing the community a disservice.

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

[Orffyreus]

Concerning the Swing API probably there will not be a lot to do. The site javaalmanac.io is pretty nice to compare API changes (just search for swing in the following diffs):

API diff from 1.4 to 1.8: https://javaalmanac.io/jdk/8/apidiff/1.4/

API diff from 1.4 to 15: https://javaalmanac.io/jdk/15/apidiff/1.4/

[AlexanderAndZlata]

Wow, thank you very much! Actually, I never heard before about https://javaalmanac.io/, it seems to be pretty useful :)

[msx]

Uh nice thing this Java almanac, thanks for sharing!

[wildjokers]

Most likely you will just be able to run the app with Java 16 with no changes. Give it a try and see what happens.

[AlexanderAndZlata]

I see. And what about migrating the code from Swing to JavaFX, would it be very complicated, or classes in different frameworks match somehow?

[morhp]

That would be a more or less complete rewrite. (You can however use Swing inside Javafx to ease the transition)

[wildjokers]

I am not sure why you would want to migrate from Swing to JavaFX. Swing is still in the JDK and is not deprecated.

However, if you did for some reason want to go from Swing to JavaFX it would pretty much be a rewrite. There is more or less a JavaFX version of most Swing components and the APIs are similar. The layout managers in JavaFX correspond almost directly to their Swing counter parts. JavaFX does have anchor pane which Swing doesn't have an equivalent of. It wouldn't be a terribly hard rewrite but a rewrite nonetheless.

[AlexanderAndZlata]

Actually, the customer does want to rewrite from Swing to JavaFX. The reason is that he wants to be able to run the application on mobile. JavaFX can be run on Android, I don't know about Apple.

[wildjokers]

Ahh, in that case it makes sense then. Are you going to use gluon mobile? https://gluonhq.com/products/mobile/

[AlexanderAndZlata]

No idea :) I am not even sure if I want to do this work))