java.lang.AssertionError: isSubtype 12
   at com.sun.tools.javac.code.Types$5.visitType(Types.java:423)
   at com.sun.tools.javac.code.Types$5.visitType(Types.java:403)
   at com.sun.tools.javac.code.Types$DefaultTypeVisitor.visitMethodType(Types.java:3747)
   at com.sun.tools.javac.code.Type$MethodType.accept(Type.java:886)
   at com.sun.tools.javac.code.Types$DefaultTypeVisitor.visit(Types.java:3743)
   at com.sun.tools.javac.code.Types.isSubtype(Types.java:399)
   at com.sun.tools.javac.code.Types.isSubtypeNoCapture(Types.java:378)
   at com.sun.tools.javac.code.Types$5.visitClassType(Types.java:484)
   at com.sun.tools.javac.code.Types$5.visitClassType(Types.java:403)
   at com.sun.tools.javac.code.Type$ClassType.accept(Type.java:583)
   at com.sun.tools.javac.code.Types$DefaultTypeVisitor.visit(Types.java:3743)
   at com.sun.tools.javac.code.Types.isSubtype(Types.java:399)
   at com.sun.tools.javac.code.Types.isSubtype(Types.java:375)
   at com.sun.tools.javac.code.Types.isSubtypeUnchecked(Types.java:346)
   at com.sun.tools.javac.code.Types.isConvertible(Types.java:284)
   at com.sun.tools.javac.code.Types.isAssignable(Types.java:1620)
   at com.sun.tools.javac.code.Types.isAssignable(Types.java:1583)
   at com.sun.tools.javac.model.JavacTypes.isAssignable(JavacTypes.java:99)
   at org.netbeans.modules.java.hints.bugs.CollectionRemove.run(CollectionRemove.java:224)
   at org.netbeans.modules.java.hints.bugs.CollectionRemove.collectionContains(CollectionRemove.java:112)
Caused: java.lang.reflect.InvocationTargetException
   at sun.reflect.GeneratedMethodAccessor153.invoke(GeneratedMethodAccessor153.java:0)
   at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
   at java.lang.reflect.Method.invoke(Method.java:616)
   at org.netbeans.modules.java.hints.jackpot.code.CodeHintProviderImpl$WorkerImpl.createErrors(CodeHintProviderImpl.java:280)
   at org.netbeans.modules.java.hints.jackpot.impl.hints.HintsInvoker.runHint(HintsInvoker.java:742)
   at org.netbeans.modules.java.hints.jackpot.impl.hints.HintsInvoker.doComputeHints(HintsInvoker.java:519)
   at org.netbeans.modules.java.hints.jackpot.impl.hints.HintsInvoker.computeHintsImpl(HintsInvoker.java:275)
   at org.netbeans.modules.java.hints.jackpot.impl.hints.HintsInvoker.computeHints(HintsInvoker.java:226)
   at org.netbeans.modules.java.hints.jackpot.impl.hints.HintsInvoker.computeHints(HintsInvoker.java:185)
   at org.netbeans.modules.java.hints.jackpot.impl.hints.HintsInvoker.computeHints(HintsInvoker.java:142)
   at org.netbeans.modules.java.hints.jackpot.impl.hints.HintsTask.run(HintsTask.java:107)
   at org.netbeans.modules.java.hints.jackpot.impl.hints.HintsTask.run(HintsTask.java:77)
   at org.netbeans.modules.java.source.JavaSourceAccessor$CancelableTaskWrapper.run(JavaSourceAccessor.java:324)
   at org.netbeans.modules.parsing.impl.TaskProcessor.callParserResultTask(TaskProcessor.java:618)
   at org.netbeans.modules.parsing.impl.TaskProcessor$CompilationJob.run(TaskProcessor.java:795)
   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:679)