Several times a day I get an editor error:
"Presentation compiler crashed while type checking this file: java.lang.NullPointerException"

Code completion is broken for this file until I restart Eclipse. Other source files work OK.

Stack-trace:

2013-01-30 17:43:32,006 ERROR [main] - org.scala-ide.sdt.core - org.scala-ide.sdt.core - org.scala-ide.sdt.core - 0 - AT: RangePosition(C:\Users\m\workspace\BlueflowOnline\src\main\scala\blueflow\online\MainUI.scala, 257, 257, 268)
java.lang.NullPointerException
	at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$addDefaultGetters$2$$anonfun$apply$14.apply(Namers.scala:1169)
	at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$addDefaultGetters$2.apply(Namers.scala:1102)
	at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$addDefaultGetters$2.apply(Namers.scala:1099)
	at scala.collection.LinearSeqOptimized$class.foldLeft(LinearSeqOptimized.scala:110)
	at scala.collection.immutable.List.foldLeft(List.scala:78)
	at scala.tools.nsc.typechecker.Namers$Namer.addDefaultGetters(Namers.scala:1099)
	at scala.tools.nsc.typechecker.Namers$Namer.methodSig(Namers.scala:1027)
	at scala.tools.nsc.typechecker.Namers$Namer.getSig$1(Namers.scala:1305)
	at scala.tools.nsc.typechecker.Namers$Namer.typeSig(Namers.scala:1347)
	at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$monoTypeCompleter$1$$anonfun$apply$1.apply$mcV$sp(Namers.scala:709)
	at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$monoTypeCompleter$1$$anonfun$apply$1.apply(Namers.scala:708)
	at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$monoTypeCompleter$1$$anonfun$apply$1.apply(Namers.scala:708)
	at scala.tools.nsc.typechecker.Namers$Namer.scala$tools$nsc$typechecker$Namers$Namer$$logAndValidate(Namers.scala:1385)
	at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$monoTypeCompleter$1.apply(Namers.scala:708)
	at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$monoTypeCompleter$1.apply(Namers.scala:707)
	at scala.tools.nsc.typechecker.Namers$$anon$1.completeImpl(Namers.scala:1496)
	at scala.tools.nsc.typechecker.Namers$LockingTypeCompleter$class.complete(Namers.scala:1504)
	at scala.tools.nsc.typechecker.Namers$$anon$1.complete(Namers.scala:1494)
	at scala.reflect.internal.Symbols$Symbol.info(Symbols.scala:1217)
	at scala.reflect.internal.Symbols$Symbol.tpe(Symbols.scala:1189)
	at scala.reflect.internal.Symbols$Symbol.tpeHK(Symbols.scala:1190)
	at scala.reflect.internal.Types$Type.computeMemberType(Types.scala:749)
	at scala.reflect.internal.Symbols$MethodSymbol.typeAsMemberOf(Symbols.scala:2597)
	at scala.reflect.internal.Types$Type.memberType(Types.scala:744)
	at scala.tools.nsc.typechecker.Infer$Inferencer.checkAccessible(Infer.scala:356)
	at scala.tools.nsc.typechecker.Typers$Typer.scala$tools$nsc$typechecker$Typers$Typer$$makeAccessible(Typers.scala:598)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$94.apply(Typers.scala:4700)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$94.apply(Typers.scala:4700)
	at scala.tools.nsc.typechecker.Typers$Typer.silent(Typers.scala:731)
	at scala.tools.nsc.typechecker.Typers$Typer.scala$tools$nsc$typechecker$Typers$Typer$$typedSelect$1(Typers.scala:4696)
	at scala.tools.nsc.typechecker.Typers$Typer.typedSelectOrSuperCall$1(Typers.scala:4781)
	at scala.tools.nsc.typechecker.Typers$Typer.typed1(Typers.scala:5380)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:5458)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$87.apply(Typers.scala:4458)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$87.apply(Typers.scala:4458)
	at scala.tools.nsc.typechecker.Typers$Typer.silent(Typers.scala:721)
	at scala.tools.nsc.typechecker.Typers$Typer.normalTypedApply$1(Typers.scala:4458)
	at scala.tools.nsc.typechecker.Typers$Typer.typedApply$1(Typers.scala:4509)
	at scala.tools.nsc.typechecker.Typers$Typer.typed1(Typers.scala:5381)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:5458)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:5526)
	at scala.tools.nsc.typechecker.Typers$Typer.computeType(Typers.scala:5621)
	at scala.tools.nsc.typechecker.Namers$Namer.assignTypeToTree(Namers.scala:813)
	at scala.tools.nsc.typechecker.Namers$Namer.getSig$1(Namers.scala:1319)
	at scala.tools.nsc.typechecker.Namers$Namer.typeSig(Namers.scala:1347)
	at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$monoTypeCompleter$1$$anonfun$apply$1.apply$mcV$sp(Namers.scala:709)
	at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$monoTypeCompleter$1$$anonfun$apply$1.apply(Namers.scala:708)
	at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$monoTypeCompleter$1$$anonfun$apply$1.apply(Namers.scala:708)
	at scala.tools.nsc.typechecker.Namers$Namer.scala$tools$nsc$typechecker$Namers$Namer$$logAndValidate(Namers.scala:1385)
	at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$monoTypeCompleter$1.apply(Namers.scala:708)
	at scala.tools.nsc.typechecker.Namers$Namer$$anonfun$monoTypeCompleter$1.apply(Namers.scala:707)
	at scala.tools.nsc.typechecker.Namers$$anon$1.completeImpl(Namers.scala:1496)
	at scala.tools.nsc.typechecker.Namers$LockingTypeCompleter$class.complete(Namers.scala:1504)
	at scala.tools.nsc.typechecker.Namers$$anon$1.complete(Namers.scala:1494)
	at scala.reflect.internal.Symbols$Symbol.info(Symbols.scala:1217)
	at scala.reflect.internal.Symbols$Symbol.initialize(Symbols.scala:1352)
	at scala.tools.nsc.typechecker.MethodSynthesis$MethodSynth$class.addDerivedTrees(MethodSynthesis.scala:224)
	at scala.tools.nsc.typechecker.Namers$Namer.addDerivedTrees(Namers.scala:55)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$29.apply(Typers.scala:1860)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$29.apply(Typers.scala:1860)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$rewrappingWrapperTrees$1.apply(Typers.scala:1798)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$rewrappingWrapperTrees$1.apply(Typers.scala:1795)
	at scala.collection.TraversableLike$$anonfun$flatMap$1.apply(TraversableLike.scala:251)
	at scala.collection.TraversableLike$$anonfun$flatMap$1.apply(TraversableLike.scala:251)
	at scala.collection.immutable.List.foreach(List.scala:309)
	at scala.collection.TraversableLike$class.flatMap(TraversableLike.scala:251)
	at scala.collection.AbstractTraversable.flatMap(Traversable.scala:105)
	at scala.tools.nsc.typechecker.Typers$Typer.typedTemplate(Typers.scala:1860)
	at scala.tools.nsc.typechecker.Typers$Typer.typedClassDef(Typers.scala:1726)
	at scala.tools.nsc.typechecker.Typers$Typer.typed1(Typers.scala:5400)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:5458)
	at scala.tools.nsc.typechecker.Typers$Typer.scala$tools$nsc$typechecker$Typers$Typer$$typedStat$1(Typers.scala:2770)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$55.apply(Typers.scala:2870)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$55.apply(Typers.scala:2870)
	at scala.collection.immutable.List.loop$1(List.scala:164)
	at scala.collection.immutable.List.mapConserve(List.scala:180)
	at scala.tools.nsc.typechecker.Typers$Typer.typedStats(Typers.scala:2870)
	at scala.tools.nsc.typechecker.Typers$Typer.typedPackageDef$1(Typers.scala:5127)
	at scala.tools.nsc.typechecker.Typers$Typer.typed1(Typers.scala:5404)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:5458)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:5509)
	at scala.tools.nsc.typechecker.Analyzer$typerFactory$$anon$3.apply(Analyzer.scala:98)
	at scala.tools.nsc.Global$GlobalPhase.applyPhase(Global.scala:461)
	at scala.tools.nsc.interactive.Global$TyperRun$$anonfun$applyPhase$1.apply(Global.scala:1085)
	at scala.tools.nsc.interactive.Global$TyperRun$$anonfun$applyPhase$1.apply(Global.scala:1085)
	at scala.reflect.internal.SymbolTable.atPhase(SymbolTable.scala:201)
	at scala.tools.nsc.interactive.Global$TyperRun.applyPhase(Global.scala:1085)
	at scala.tools.nsc.interactive.Global$TyperRun.typeCheck(Global.scala:1078)
	at scala.tools.nsc.interactive.Global.scala$tools$nsc$interactive$Global$$typeCheck(Global.scala:563)
	at scala.tools.nsc.interactive.Global$$anonfun$backgroundCompile$5$$anonfun$apply$7.apply(Global.scala:479)
	at scala.tools.nsc.interactive.Global$$anonfun$backgroundCompile$5.apply(Global.scala:475)
	at scala.tools.nsc.interactive.Global$$anonfun$backgroundCompile$5.apply(Global.scala:475)
	at scala.collection.TraversableLike$WithFilter$$anonfun$foreach$1.apply(TraversableLike.scala:772)
	at scala.collection.immutable.List.foreach(List.scala:309)
	at scala.collection.TraversableLike$WithFilter.foreach(TraversableLike.scala:771)
	at scala.tools.nsc.interactive.Global.backgroundCompile(Global.scala:475)
	at scala.tools.nsc.interactive.PresentationCompilerThread.run(PresentationCompilerThread.scala:25)