How do I have integrated support for Scala inside newer versions of Eclipse (2023-06)?

Question

I have a large java project with a bit of scala in it and it builds sucessfully with gradle on command line. Inside the IDE, it builds sucessfully thanks to an old plugin named Scala-IDE which is not maintained anymore and binds me to an older version of Eclipse, which is unsatisfying. I found another plugin named metals but its update site appears to be broken. Also, I tried to build the project directly from https://github.com/scalameta/metals-eclipse but unfortunately, the project is archived and I also have a build error:

[ERROR] Failed to resolve target definition P:\git\metals-eclipse\target-platform\target-platform.target: Could not find "com.google.gson/2.7.0.v20170129-0911" in the repositories of the current location

I could find this inside the file target-platform.target:

<location includeAllPlatforms="false" includeConfigurePhase="true" includeMode="planner" includeSource="true" type="InstallableUnit">
  <unit id="com.google.gson" version="2.7.0.v20170129-0911"/>
  <repository location="https://download.eclipse.org/tools/orbit/downloads/latest-R/"/>
</location>

After updating the URL from https://download.eclipse.org/tools/orbit/downloads/latest-R/ to https://download.eclipse.org/tools/orbit/downloads/drops/R20220830213456/repository/ in target-platform.target I have a new build error:

[ERROR] Cannot resolve target definition:
[ERROR]   Software being installed: org.eclipse.mylyn.wikitext 3.0.47.202305042122
[ERROR]   Missing requirement: com.google.guava 31.1.0.jre requires 'java.package; com.google.common.util.concurrent.internal [1.0.0,2.0.0)' but it could not be found
[ERROR]   Cannot satisfy dependency: org.eclipse.mylyn.wikitext 3.0.47.202305042122 depends on: java.package; com.google.common.base [31.1.0,32.0.0)
[ERROR]
[ERROR] Failed to resolve target definition P:\git\metals-eclipse\target-platform\target-platform.target: See log for details -> [Help 1]

How can I fix the build ? Any other solution to have full scala support inside Eclipse ?

Answer 1

As you can see in the following discussions

• any eclipse alternative to scala
• how to install scala plugin for eclipse
• Future plans for the Eclipse Metals plugin

eclipse doesn't have good support for scala. Unless you need something specific from eclipse, the best options you have today are

• Intellij
• metals: it has integration with many IDEs and editors such as vs code, vim, sublime, emacs.