Re: NYIException

[Andrew Haley]

Andy Walter writes:
 > Hi Andrew,
 > 
 > On Monday 29 September 2003 19:40, Andrew Haley wrote:
 > > Throwing an appropriate message will help, of course, but one of
 > > the advantages of gcj is that you can pre-link and you know you
 > > won't get runtime linkage errors -- the linker has resolved
 > > everything.  Having dummy implementations loses this gcj
 > > advantage.
 > 
 > Dummy implementations that do nothing are a really bad thing, I
 > agree. But a dummy implementation that either returns with the
 > correct result or throws a NYIException makes it clear to the user
 > what had happened.
 > 
 > Currently, we have those dummy methods anyway - and can't get rid
 > of them, because some methods are partly, but not completely,
 > implemented. With a new Exception class, the gcj linker could stop
 > with an error message when such a method is instantiated and
 > thrown.

Err, no.  Linking happens at link time; throwing happens at runtime!
But this gives me an idea.  I can parse the class at compile time, and
if I see any references to a method that throws such an exception I
can warn the user about it.  That would be *much* better.  It wouldn't
be complete because there might be partly implemented subclasses that
aren't directly referenced, but it would be better than nothing.

 > If we abuse any existing JDK Exeption for it, this would not be
 > possible.

True.

Andrew.