java.lang.NullPointerException
   at org.openide.util.Exceptions$AnnException.getMessage(Exceptions.java:238)
   at org.openide.util.Exceptions$AnnException.toString(Exceptions.java:321)
   at java.util.Objects.toString(Objects.java:159)
   at java.lang.Throwable.initCause(Throwable.java:457)
   at org.openide.util.Exceptions$AnnException.findOrCreate0(Exceptions.java:279)
   at org.openide.util.Exceptions$AnnException.findOrCreate(Exceptions.java:256)
   at org.openide.util.Exceptions.attachMessage(Exceptions.java:85)
   at org.netbeans.modules.java.source.parsing.JavacParser.dumpSource(JavacParser.java:997)
   at org.netbeans.modules.java.source.parsing.JavacParser.moveToPhase(JavacParser.java:689)
   at org.netbeans.modules.java.source.parsing.JavacParser.getResult(JavacParser.java:520)
   at org.netbeans.modules.java.source.parsing.JavacParser.getResult(JavacParser.java:173)
   at org.netbeans.modules.parsing.impl.TaskProcessor.callGetResult(TaskProcessor.java:608)
   at org.netbeans.modules.parsing.impl.SourceCache.getResult(SourceCache.java:247)
   at org.netbeans.modules.parsing.impl.TaskProcessor$CompilationJob.run(TaskProcessor.java:720)
   at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:507)
   at java.util.concurrent.FutureTask.run(FutureTask.java:266)
   at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
   at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
   at java.lang.Thread.run(Thread.java:724)