Eclipse:
Build id: 20100218-1602
JVM: SDK 1.6.0_23
Scala IDE plug-in for Eclipse:
Version: 0.8.0.201102100000
Feature Id: org.scala-ide.sdt.feature
Project:
Scala Library: 2.8.1-final
New Scala project - single file:
<FirstSwingApp.scala>
package com.xo.play

import scala.swing._
import event._

object FirstSwingApp extends SimpleGUIApplication
{
def top = new MainFrame {
title = "First Swing App"
contents = new Button {
text = "Click me"
}
}
}

object ReactiveSwingApp extends SimpleGUIApplication {
def top = new MainFrame {
title = "Reactive Swing App"
val button = new Button {
text = "Click me"
}
val label = new Label {
text = "No button clicks registered"
}
contents = new BoxPanel(Orientation.Vertical) {
contents += button
contents += label
border = Swing.EmptyBorder(30, 30, 10, 30)
}
listenTo(button)
var nClicks = 0
reactions += {
case ButtonClicked(b) =>
nClicks += 1
label.text = "Number of button clicks: "+ nClicks
}
}
}
</FirstSwingApp.scala>


Error log (after hitting space and then backspace to force a change, hitting Ctrl-S causes this):
!SESSION 2011-02-11 14:43:57.653 -----------------------------------------------
eclipse.buildId=
java.version=1.6.0_23
java.vendor=Sun Microsystems Inc.
BootLoader constants: OS=win32, ARCH=x86, WS=win32, NL=en_US
Framework arguments: -product org.eclipse.epp.package.java.product
Command-line arguments: -os win32 -ws win32 -arch x86 -product org.eclipse.epp.package.java.product

!ENTRY org.scala-ide.sdt.core 4 4 2011-02-11 14:44:56.683
!MESSAGE class java.util.MissingFormatArgumentException:Format specifier 's'
!STACK 0
java.util.MissingFormatArgumentException: Format specifier 's'
at java.util.Formatter.format(Formatter.java:2432)
at java.util.Formatter.format(Formatter.java:2367)
at java.lang.String.format(String.java:2769)
at scala.collection.immutable.StringLike$class.format(StringLike.scala:252)
at scala.collection.immutable.StringOps.format(StringOps.scala:31)
at scala.tools.eclipse.util.Defensive$.log(Defensive.scala:32)
at scala.tools.eclipse.util.Defensive$.check(Defensive.scala:61)
at scala.tools.eclipse.javaelements.ScalaMemberElementInfo$class.setSourceRange0(ScalaElements.scala:229)
at scala.tools.eclipse.javaelements.ScalaSourceMethodInfo.setSourceRange0(ScalaElements.scala:281)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser.setSourceRange(ScalaStructureBuilder.scala:781)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser$DefOwner$class.addDef(ScalaStructureBuilder.scala:645)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser$Builder.addDef(ScalaStructureBuilder.scala:754)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser.traverse(ScalaStructureBuilder.scala:805)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser$$anonfun$traverse$1.apply(ScalaStructureBuilder.scala:813)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser$$anonfun$traverse$1.apply(ScalaStructureBuilder.scala:813)
at scala.collection.LinearSeqOptimized$class.foreach(LinearSeqOptimized.scala:61)
at scala.collection.immutable.List.foreach(List.scala:45)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser.traverse(ScalaStructureBuilder.scala:813)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser$$anonfun$traverse$1.apply(ScalaStructureBuilder.scala:813)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser$$anonfun$traverse$1.apply(ScalaStructureBuilder.scala:813)
at scala.collection.LinearSeqOptimized$class.foreach(LinearSeqOptimized.scala:61)
at scala.collection.immutable.List.foreach(List.scala:45)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser.traverse(ScalaStructureBuilder.scala:813)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser$$anonfun$traverse$1.apply(ScalaStructureBuilder.scala:813)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser$$anonfun$traverse$1.apply(ScalaStructureBuilder.scala:813)
at scala.collection.LinearSeqOptimized$class.foreach(LinearSeqOptimized.scala:61)
at scala.collection.immutable.List.foreach(List.scala:45)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser.traverse(ScalaStructureBuilder.scala:813)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser.traverse(ScalaStructureBuilder.scala:785)
at scala.tools.eclipse.javaelements.ScalaCompilationUnit$$anonfun$buildStructure$1$$anonfun$apply$2$$anonfun$apply$mcZ$sp$1$$anonfun$apply$mcV$sp$3.apply(ScalaCompilationUnit.scala:96)
at scala.tools.eclipse.javaelements.ScalaCompilationUnit$$anonfun$buildStructure$1$$anonfun$apply$2$$anonfun$apply$mcZ$sp$1$$anonfun$apply$mcV$sp$3.apply(ScalaCompilationUnit.scala:95)
at scala.tools.eclipse.ScalaPresentationCompiler.withUntypedTree(ScalaPresentationCompiler.scala:108)
at scala.tools.eclipse.javaelements.ScalaCompilationUnit$$anonfun$buildStructure$1$$anonfun$apply$2$$anonfun$apply$mcZ$sp$1.apply$mcV$sp(ScalaCompilationUnit.scala:95)
at scala.tools.eclipse.javaelements.ScalaCompilationUnit$$anonfun$buildStructure$1$$anonfun$apply$2$$anonfun$apply$mcZ$sp$1.apply(ScalaCompilationUnit.scala:94)
at scala.tools.eclipse.javaelements.ScalaCompilationUnit$$anonfun$buildStructure$1$$anonfun$apply$2$$anonfun$apply$mcZ$sp$1.apply(ScalaCompilationUnit.scala:94)
at scala.tools.nsc.interactive.util.InterruptReq.liftedTree1$1(InterruptReq.scala:22)
at scala.tools.nsc.interactive.util.InterruptReq.execute(InterruptReq.scala:21)
at scala.tools.nsc.interactive.Global.pollForWork(Global.scala:252)
at scala.tools.nsc.interactive.PresentationCompilerThread.run(PresentationCompilerThread.scala:19)

!ENTRY org.scala-ide.sdt.core 4 4 2011-02-11 14:44:56.730
!MESSAGE class java.util.MissingFormatArgumentException:Format specifier 's'
!STACK 0
java.util.MissingFormatArgumentException: Format specifier 's'
at java.util.Formatter.format(Formatter.java:2432)
at java.util.Formatter.format(Formatter.java:2367)
at java.lang.String.format(String.java:2769)
at scala.collection.immutable.StringLike$class.format(StringLike.scala:252)
at scala.collection.immutable.StringOps.format(StringOps.scala:31)
at scala.tools.eclipse.util.Defensive$.log(Defensive.scala:32)
at scala.tools.eclipse.util.Defensive$.check(Defensive.scala:61)
at scala.tools.eclipse.javaelements.ScalaMemberElementInfo$class.setSourceRange0(ScalaElements.scala:229)
at scala.tools.eclipse.javaelements.ScalaSourceMethodInfo.setSourceRange0(ScalaElements.scala:281)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser.setSourceRange(ScalaStructureBuilder.scala:781)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser$DefOwner$class.addDef(ScalaStructureBuilder.scala:645)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser$Builder.addDef(ScalaStructureBuilder.scala:754)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser.traverse(ScalaStructureBuilder.scala:805)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser$$anonfun$traverse$1.apply(ScalaStructureBuilder.scala:813)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser$$anonfun$traverse$1.apply(ScalaStructureBuilder.scala:813)
at scala.collection.LinearSeqOptimized$class.foreach(LinearSeqOptimized.scala:61)
at scala.collection.immutable.List.foreach(List.scala:45)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser.traverse(ScalaStructureBuilder.scala:813)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser$$anonfun$traverse$1.apply(ScalaStructureBuilder.scala:813)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser$$anonfun$traverse$1.apply(ScalaStructureBuilder.scala:813)
at scala.collection.LinearSeqOptimized$class.foreach(LinearSeqOptimized.scala:61)
at scala.collection.immutable.List.foreach(List.scala:45)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser.traverse(ScalaStructureBuilder.scala:813)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser$$anonfun$traverse$1.apply(ScalaStructureBuilder.scala:813)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser$$anonfun$traverse$1.apply(ScalaStructureBuilder.scala:813)
at scala.collection.LinearSeqOptimized$class.foreach(LinearSeqOptimized.scala:61)
at scala.collection.immutable.List.foreach(List.scala:45)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser.traverse(ScalaStructureBuilder.scala:813)
at scala.tools.eclipse.javaelements.ScalaStructureBuilder$StructureBuilderTraverser.traverse(ScalaStructureBuilder.scala:785)
at scala.tools.eclipse.javaelements.ScalaCompilationUnit$$anonfun$buildStructure$1$$anonfun$apply$2$$anonfun$apply$mcZ$sp$1$$anonfun$apply$mcV$sp$3.apply(ScalaCompilationUnit.scala:96)
at scala.tools.eclipse.javaelements.ScalaCompilationUnit$$anonfun$buildStructure$1$$anonfun$apply$2$$anonfun$apply$mcZ$sp$1$$anonfun$apply$mcV$sp$3.apply(ScalaCompilationUnit.scala:95)
at scala.tools.eclipse.ScalaPresentationCompiler.withUntypedTree(ScalaPresentationCompiler.scala:108)
at scala.tools.eclipse.javaelements.ScalaCompilationUnit$$anonfun$buildStructure$1$$anonfun$apply$2$$anonfun$apply$mcZ$sp$1.apply$mcV$sp(ScalaCompilationUnit.scala:95)
at scala.tools.eclipse.javaelements.ScalaCompilationUnit$$anonfun$buildStructure$1$$anonfun$apply$2$$anonfun$apply$mcZ$sp$1.apply(ScalaCompilationUnit.scala:94)
at scala.tools.eclipse.javaelements.ScalaCompilationUnit$$anonfun$buildStructure$1$$anonfun$apply$2$$anonfun$apply$mcZ$sp$1.apply(ScalaCompilationUnit.scala:94)
at scala.tools.nsc.interactive.util.InterruptReq.liftedTree1$1(InterruptReq.scala:22)
at scala.tools.nsc.interactive.util.InterruptReq.execute(InterruptReq.scala:21)
at scala.tools.nsc.interactive.Global.pollForWork(Global.scala:252)
at scala.tools.nsc.interactive.Global.pollForWork(Global.scala:256)
at scala.tools.nsc.interactive.PresentationCompilerThread.run(PresentationCompilerThread.scala:19)