Typesafe Activator NoSuchMethodError

Question

I'm having an issue running Typesafe Activator. I had it working fine for a while on version 1.1.3. It was a Java Play project. Recently however it auto-updated to 1.2.1 and has stopped working. First things first, my Java version is 1.7.0_25-b17. I'm running Windows 8.1 and running activator from PowerShell.

Here is the error output:

The system cannot find the file C:\Users\[my name]\.activator\1.2.3\activatorconfig.txt.
The system cannot find the file C:\Users\[my name]\.activator\activatorconfig.txt.
Checking for a newer version of Activator (current version 1.2.1)...
java.lang.NoSuchMethodError: scala.util.matching.Regex.unapplySeq(Ljava/lang/CharSequence;)Lscala/Option;
        at activator.ActivatorLauncher.downloadLatestVersion(ActivatorLauncher.scala:164)
        at activator.ActivatorLauncher.checkForUpdatedVersion(ActivatorLauncher.scala:206)
        at activator.ActivatorLauncher.run(ActivatorLauncher.scala:27)
        at xsbt.boot.Launch$$anonfun$run$1.apply(Launch.scala:109)
        at xsbt.boot.Launch$.withContextLoader(Launch.scala:129)
        at xsbt.boot.Launch$.run(Launch.scala:109)
        at xsbt.boot.Launch$$anonfun$apply$1.apply(Launch.scala:36)
        at xsbt.boot.Launch$.launch(Launch.scala:117)
        at xsbt.boot.Launch$.apply(Launch.scala:19)
        at xsbt.boot.Boot$.runImpl(Boot.scala:44)
        at xsbt.boot.Boot$.main(Boot.scala:20)
        at xsbt.boot.Boot.main(Boot.scala)
Error during sbt execution: java.lang.NoSuchMethodError: scala.util.matching.Reg
ex.unapplySeq(Ljava/lang/CharSequence;)Lscala/Option;

This is also happening with a fresh download of activator. It happens whenever I try to run activator or activator ui. Other commands fail with similar messages, except for activator help, which runs fine. Does anyone know what's wrong here? Am I missing something? Theoretically Activator should run as long as I have JDK6+, right? I'm using the version that's supposed to include dependencies, and as far as I can tell, that missing method actually does appear to be there. This is really holding me up since I have to get back to work on that Play project.

Answer 1

I had a similar (although not quite identical) error a few minutes ago; the workaround described on this page fixed it for me...

Answer 2

deleting ~/.activator/version-0.properties

Answer 3

I just figured it out - in my username directory (Windows 7 x64) there was a folder named ".sbt". In there was a folder named "boot".
In there were a handful of scala folders, each folder a different version.
I deleted all of them except the latest scala version folder (scala-2.11.1). Once I did that, Activator booted up successfully (right click on the Activator.bat file).