build with gradle v9 support

[daeho-ro]

🔧 Feature request 🔧

Description

support gradle v9. currently there is an error

  Welcome to Gradle 9.0.0!
  
  Here are the highlights of this release:
   - Configuration Cache is the recommended execution mode
   - Gradle requires JVM 17 or higher to run
   - Build scripts use Kotlin 2.2 and Groovy 4.0
   - Improved Kotlin DSL script compilation avoidance
  
  For more details see https://docs.gradle.org/9.0.0/release-notes.html
  
  Starting a Gradle Daemon (subsequent builds will be faster)
  
  FAILURE: Build failed with an exception.
  
  * What went wrong:
  org/gradle/api/artifacts/SelfResolvingDependency
  > org.gradle.api.artifacts.SelfResolvingDependency
  

Examples

Motivation

getting newer build system

Alternatives

[daveyarwood]

Hi @daeho-ro, thanks for the issue!

I don't necessarily see this as a blocker, since you can (and should) use the ./gradlew wrapper script to ensure that we're all using the same version of Gradle when developing Alda.

On the other hand, I'm generally in favor of keeping tooling up to date, so if somebody is interested in making a PR for this, I'll be happy to review, test and merge it.

[daveyarwood]

Capturing the context here, for posterity (especially since we're on Slack's free plan and these Slack messages will eventually disappear 👻)

@conditionals took a stab at upgrading the Gradle wrapper to 9.1.0 in #511, however, the CI build failed with this output:

Building build/libs/alda-player-fat.jar...
Downloading https://services.gradle.org/distributions/gradle-9.1.0-bin.zip
............10%.............20%.............30%.............40%.............50%............60%.............70%.............80%.............90%.............100%

Welcome to Gradle 9.1.0!

Here are the highlights of this release:
 - Full Java 25 support
 - Native task graph visualization
 - Enhanced console output

For more details see https://docs.gradle.org/9.1.0/release-notes.html

Starting a Gradle Daemon (subsequent builds will be faster)

FAILURE: Build failed with an exception.

* What went wrong:
Gradle requires JVM 17 or later to run. Your build is currently configured to use JVM 8.

* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to generate a Build Scan (Powered by Develocity).
> Get more help at https://help.gradle.org.

Exited with code exit status 1

We discussed this a little on Slack, and I said the following:

Hi @ian, thanks for the PR! A long time ago, I decided to target an older version of Java in order to ensure that Alda will work on as many people's computers as possible. My target user is someone who doesn't necessarily know anything about Java or know what version of Java they have installed, and I want Alda to Just Work:tm: on that person's computer.

That being said, I don't know how many people still have Java 8 installed at this point - it's ancient! So I wouldn't be opposed to bumping that version. But I'm worried that Java 17 might be too recent and we'd end up having a lot of users reporting that Alda doesn't work on their machine because their Java version is too old. Does that make sense?

Also just to reiterate, you can (and should) use the gradlew wrapper script in the repo. It shouldn't matter what version of Gradle you have installed globally.

---

I thought about this a little more just now, and I'm thinking that maybe we can have our cake and eat it too. I believe the CI build is failing because it's using this Docker image that I created a long time ago, which has JDK 8 installed.

But I do think it's possible that we could update that Docker image to use JDK 17 (or even a newer version?) and still target JDK 8, and that might still work fine on end users' machines if they have Java 8 installed.

The good news is that the Alda CI build specifically includes a test step where we install and run Alda on a Docker image with OpenJDK 8. So we could actually test this out pretty easily.

@daeho-ro @conditionals If either of you are interested in helping me with this, I think the next steps would be:

1. Determine which CircleCI base image we should be using for the CI build.
2. Make a PR to update the CI build Docker image to use the newer base image. If someone is able to run and test that locally and confirm it works, I can push the image up to Docker Hub so that it's available for the Alda CI build to use.
3. Retry the build for chore: upgrade Gradle wrapper to 9.1.0 #511 and see if that resolves the issue.
4. If the CI build passes, then I think that will prove that the CI build generates releases that work on older versions of Java back to JDK 8, and at that point we can merge chore: upgrade Gradle wrapper to 9.1.0 #511.