java.lang.IllegalArgumentException: Invalid ClassPath root: file:/usr/lib/jvm/java-1.6.0-openjdk-1.6.0.0/jre/lib/rhino.jar/. The root must be a folder.
        at org.netbeans.api.java.classpath.ClassPath$Entry.getRoot(ClassPath.java:686)
        at org.netbeans.api.java.classpath.ClassPath.createRoots(ClassPath.java:271)
        at org.netbeans.api.java.classpath.ClassPath.getRoots(ClassPath.java:252)
        at org.netbeans.api.java.classpath.ClassPath.findAllResources(ClassPath.java:376)
        at org.netbeans.api.java.source.SourceUtils.getFile(SourceUtils.java:393)
        at org.netbeans.api.java.source.SourceUtils.getFile(SourceUtils.java:356)
        at org.netbeans.modules.java.source.TreeLoader.loadTreeFor(TreeLoader.java:135)
        at com.sun.tools.javac.code.Symbol$ParamSymbol.getSimpleName(Symbol.java:1045)
        at com.sun.tools.javac.code.Symbol$ParamSymbol.getSimpleName(Symbol.java:1012)
        at org.netbeans.modules.java.navigation.ElementScanningTask.createHtmlHeader(ElementScanningTask.java:297)
        at org.netbeans.modules.java.navigation.ElementScanningTask.element2description(ElementScanningTask.java:241)
        at org.netbeans.modules.java.navigation.ElementScanningTask.addMembers(ElementScanningTask.java:218)
        at org.netbeans.modules.java.navigation.ElementScanningTask.run(ElementScanningTask.java:137)
        at org.netbeans.modules.java.navigation.ElementScanningTask.run(ElementScanningTask.java:86)
        at org.netbeans.api.java.source.JavaSource$CompilationJob.run(JavaSource.java:1729)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
        at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
        at java.util.concurrent.FutureTask.run(FutureTask.java:166)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
        at java.lang.Thread.run(Thread.java:636)