The Component spec does not say anything about the expected behavior of
getCursor() and setCursor() if null is provided as the value of the
'cursor' input parameter to setCursor().

null is an acceptable value for the 'cursor' parameter (ie,
a NullPointerException is not thrown) in the case of setCursor(); this should
be clearly stated in the spec, and the expected behavior in this situation should be specified.
Also, it should be specified that getCursor() returns null if there is
no cursor set on the component.