I'm running the most recent Yosemite 10.10.3 with the latest activator from Typesafe 1.3.4 and I tried creating a new Scala Project template 6 and I can no longer run the template without this error.
[info] Loading project definition from /Users/Master/x/x/project
java.lang.UnsupportedClassVersionError: play/runsupport/classloader/ApplicationClassLoaderProvider : Unsupported major.minor version 52.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
at play.sbt.run.PlayRun$.<init>(PlayRun.scala:35)
at play.sbt.run.PlayRun$.<clinit>(PlayRun.scala)
at play.sbt.PlaySettings$.defaultSettings$lzycompute(PlaySettings.scala:70)
at play.sbt.PlaySettings$.defaultSettings(PlaySettings.scala:47)
at play.sbt.Play$.projectSettings(Play.scala:26)
at sbt.Load$$anonfun$autoPluginSettings$1$1.apply(Load.scala:666)
at sbt.Load$$anonfun$autoPluginSettings$1$1.apply(Load.scala:666)
at scala.collection.TraversableLike$$anonfun$flatMap$1.apply(TraversableLike.scala:251)
at scala.collection.TraversableLike$$anonfun$flatMap$1.apply(TraversableLike.scala:251)
at scala.collection.immutable.List.foreach(List.scala:318)
at scala.collection.TraversableLike$class.flatMap(TraversableLike.scala:251)
at scala.collection.AbstractTraversable.flatMap(Traversable.scala:105)
at sbt.Load$.autoPluginSettings$1(Load.scala:666)
at sbt.Load$.sbt$Load$$expandSettings$1(Load.scala:681)
at sbt.Load$$anonfun$sbt$Load$$expandSettings$1$2.apply(Load.scala:682)
at sbt.Load$$anonfun$sbt$Load$$expandSettings$1$2.apply(Load.scala:682)
at scala.collection.IndexedSeqOptimized$class.foldl(IndexedSeqOptimized.scala:51)
at scala.collection.IndexedSeqOptimized$class.foldLeft(IndexedSeqOptimized.scala:60)
at scala.collection.mutable.WrappedArray.foldLeft(WrappedArray.scala:34)
at scala.collection.TraversableOnce$class.$div$colon(TraversableOnce.scala:138)
at scala.collection.AbstractTraversable.$div$colon(Traversable.scala:105)
at sbt.Load$.sbt$Load$$expandSettings$1(Load.scala:682)
at sbt.Load$.resolveProject(Load.scala:684)
at sbt.Load$.finalizeProject$1(Load.scala:549)
at sbt.Load$.loadTransitive(Load.scala:577)
at sbt.Load$.loadProjects$1(Load.scala:442)
at sbt.Load$.loadUnit(Load.scala:446)
at sbt.Load$$anonfun$18$$anonfun$apply$11.apply(Load.scala:281)
at sbt.Load$$anonfun$18$$anonfun$apply$11.apply(Load.scala:281)
at sbt.BuildLoader$$anonfun$componentLoader$1$$anonfun$apply$4$$anonfun$apply$5$$anonfun$apply$6.apply(BuildLoader.scala:91)
at sbt.BuildLoader$$anonfun$componentLoader$1$$anonfun$apply$4$$anonfun$apply$5$$anonfun$apply$6.apply(BuildLoader.scala:90)
at sbt.BuildLoader.apply(BuildLoader.scala:140)
at sbt.Load$.loadAll(Load.scala:334)
at sbt.Load$.loadURI(Load.scala:289)
at sbt.Load$.load(Load.scala:285)
at sbt.Load$.load(Load.scala:276)
at sbt.Load$.apply(Load.scala:130)
at sbt.Load$.defaultLoad(Load.scala:36)
at sbt.BuiltinCommands$.doLoadProject(Main.scala:481)
at sbt.BuiltinCommands$$anonfun$loadProjectImpl$2.apply(Main.scala:475)
at sbt.BuiltinCommands$$anonfun$loadProjectImpl$2.apply(Main.scala:475)
at sbt.Command$$anonfun$applyEffect$1$$anonfun$apply$2.apply(Command.scala:58)
at sbt.Command$$anonfun$applyEffect$1$$anonfun$apply$2.apply(Command.scala:58)
at sbt.Command$$anonfun$applyEffect$2$$anonfun$apply$3.apply(Command.scala:60)
at sbt.Command$$anonfun$applyEffect$2$$anonfun$apply$3.apply(Command.scala:60)
at sbt.Command$.process(Command.scala:92)
at sbt.MainLoop$$anonfun$1$$anonfun$apply$1.apply(MainLoop.scala:98)
at sbt.MainLoop$$anonfun$1$$anonfun$apply$1.apply(MainLoop.scala:98)
at sbt.State$$anon$1.process(State.scala:184)
at sbt.MainLoop$$anonfun$1.apply(MainLoop.scala:98)
at sbt.MainLoop$$anonfun$1.apply(MainLoop.scala:98)
at sbt.ErrorHandling$.wideConvert(ErrorHandling.scala:17)
at sbt.MainLoop$.next(MainLoop.scala:98)
at sbt.MainLoop$.run(MainLoop.scala:91)
at sbt.MainLoop$$anonfun$runWithNewLog$1.apply(MainLoop.scala:70)
at sbt.MainLoop$$anonfun$runWithNewLog$1.apply(MainLoop.scala:65)
at sbt.Using.apply(Using.scala:24)
at sbt.MainLoop$.runWithNewLog(MainLoop.scala:65)
at sbt.MainLoop$.runAndClearLast(MainLoop.scala:48)
at sbt.MainLoop$.runLoggedLoop(MainLoop.scala:32)
at sbt.MainLoop$.runLogged(MainLoop.scala:24)
at sbt.StandardMain$.runManaged(Main.scala:53)
at sbt.xMain.run(Main.scala:28)
at xsbt.boot.Launch$$anonfun$run$1.apply(Launch.scala:109)
at xsbt.boot.Launch$.withContextLoader(Launch.scala:128)
at xsbt.boot.Launch$.run(Launch.scala:109)
at xsbt.boot.Launch$$anonfun$apply$1.apply(Launch.scala:35)
at xsbt.boot.Launch$.launch(Launch.scala:117)
at xsbt.boot.Launch$.apply(Launch.scala:18)
at xsbt.boot.Boot$.runImpl(Boot.scala:41)
at xsbt.boot.Boot$.main(Boot.scala:17)
at xsbt.boot.Boot.main(Boot.scala)
[error] java.lang.UnsupportedClassVersionError: play/runsupport/classloader/ApplicationClassLoaderProvider : Unsupported major.minor version 52.0
The latest Play framework starting at version 2.4.0 requires Java 1.8. Upgrade to resolve.
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