java.lang.IllegalArgumentException: fileObject == null
   at org.netbeans.api.java.source.JavaSource.forFileObject(JavaSource.java:234)
   at org.netbeans.modules.debugger.jpda.projects.PreferredCCParser.getImports(PreferredCCParser.java:346)
   at org.netbeans.modules.debugger.jpda.projects.EditorContextSupport.getImports(EditorContextSupport.java:1432)
   at org.netbeans.modules.debugger.jpda.projectsui.EditorContextImpl.getImports(EditorContextImpl.java:820)
   at org.netbeans.modules.debugger.jpda.JavaEvaluator.evaluateIn(JavaEvaluator.java:139)
   at org.netbeans.modules.debugger.jpda.JavaEvaluator.evaluate(JavaEvaluator.java:107)
   at org.netbeans.modules.debugger.jpda.expr.EvaluatorExpression$AssociatedExpression.evaluate(EvaluatorExpression.java:90)
   at org.netbeans.modules.debugger.jpda.expr.EvaluatorExpression.evaluate(EvaluatorExpression.java:73)
   at org.netbeans.modules.debugger.jpda.JPDADebuggerImpl.evaluateGeneric(JPDADebuggerImpl.java:965)
   at org.netbeans.modules.debugger.jpda.JPDADebuggerImpl.evaluate(JPDADebuggerImpl.java:372)
   at org.netbeans.modules.debugger.jpda.JPDADebuggerImpl.evaluate(JPDADebuggerImpl.java:336)
   at org.netbeans.modules.debugger.jpda.projectsui.ToolTipAnnotation.run(ToolTipAnnotation.java:277)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1443)
   at org.netbeans.modules.openide.util.GlobalLookup.execute(GlobalLookup.java:68)
   at org.openide.util.lookup.Lookups.executeWith(Lookups.java:303)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2058)