JDK 11 produces a Null Pointer Exception

[athersharif]

JDK 11 produces this error when doing activator run or sbt run:

[info] Loading project definition from /Users/athersharif/dev/SidewalkWebpage/project
java.lang.NullPointerException
    at java.base/java.util.regex.Matcher.getTextLength(Matcher.java:1770)
    at java.base/java.util.regex.Matcher.reset(Matcher.java:416)
    at java.base/java.util.regex.Matcher.<init>(Matcher.java:253)
    at java.base/java.util.regex.Pattern.matcher(Pattern.java:1133)
    at java.base/java.util.regex.Pattern.split(Pattern.java:1261)
    at java.base/java.util.regex.Pattern.split(Pattern.java:1334)
    at sbt.IO$.pathSplit(IO.scala:727)
    at sbt.IO$.parseClasspath(IO.scala:825)
    at sbt.compiler.CompilerArguments.extClasspath(CompilerArguments.scala:64)
    at sbt.compiler.AggressiveCompile.withBootclasspath(AggressiveCompile.scala:51)
    at sbt.compiler.AggressiveCompile.compile2(AggressiveCompile.scala:84)
    at sbt.compiler.AggressiveCompile.compile1(AggressiveCompile.scala:71)
    at sbt.compiler.AggressiveCompile.apply(AggressiveCompile.scala:46)
    at sbt.Compiler$.apply(Compiler.scala:75)
    at sbt.Compiler$.apply(Compiler.scala:66)
    at sbt.Defaults$.sbt$Defaults$$compileTaskImpl(Defaults.scala:770)
    at sbt.Defaults$$anonfun$compileTask$1.apply(Defaults.scala:762)
    at sbt.Defaults$$anonfun$compileTask$1.apply(Defaults.scala:762)
    at scala.Function1$$anonfun$compose$1.apply(Function1.scala:47)
    at sbt.$tilde$greater$$anonfun$$u2219$1.apply(TypeFunctions.scala:42)
    at sbt.std.Transform$$anon$4.work(System.scala:64)
    at sbt.Execute$$anonfun$submit$1$$anonfun$apply$1.apply(Execute.scala:237)
    at sbt.Execute$$anonfun$submit$1$$anonfun$apply$1.apply(Execute.scala:237)
    at sbt.ErrorHandling$.wideConvert(ErrorHandling.scala:18)
    at sbt.Execute.work(Execute.scala:244)
    at sbt.Execute$$anonfun$submit$1.apply(Execute.scala:237)
    at sbt.Execute$$anonfun$submit$1.apply(Execute.scala:237)
    at sbt.ConcurrentRestrictions$$anon$4$$anonfun$1.apply(ConcurrentRestrictions.scala:160)
    at sbt.CompletionService$$anon$2.call(CompletionService.scala:30)
    at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
    at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
    at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
    at java.base/java.lang.Thread.run(Thread.java:834)
[error] (compile:compile) java.lang.NullPointerException

Switching to JDK 8 solves this. Worth investigating and fixing this as folks new to the project may have the newer version of JDK.

[misaugstad]

According to Scala documentation Java 9 and 10 require Scala 2.12.4+, 2.11.12+, or 2.10.7+. We are currently using 2.10.4. I am in the process of updating the libraries and such that we use (#1258) and hope update our version of Scala at that time as well, which should solve this!

[athersharif]

@misaugstad ah, makes sense. can certainly review the pr against this bug once it's ready :)