多项选择题
Which two statements are true if a NullPointerException is thrown on line 3 of class C？（）
A.The application will crash. B.The code on line 29 will be executed. C.The code on line 5 of class A will execute. D.The code on line 5 of class B will execute. E.The exception will be propagated back to line 27.
单项选择题 Given a method that must ensure that its parameter is not null： What， inserted at line 12， is the appropriate way to handle a null value？（）
多项选择题 Which two code fragments are most likely to cause a StackOverflowError？（）
单项选择题 What is the result？（）
