need help, level 3 test

Attached is a filter test which generated test1.java if you leave out the
<whatToShow...> element.
Can someone have a look at this and tell me how you would have to specify
<whatToShow> in this case (I've been staring on it a while now) ?
I'd also like to know how you can refer to constants defined in other
interfaces,e.g. NodeFilter.SHOW_ELEMENT.
Thanks in advance,

Jeroen
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