[jdom-interest] [Vote] NoSuchChildException

[Elliotte Rusty Harold]

-1 on returning null

You asked for a reason for a -1 vote so I'll give you mine. I was 
initially undecided, but when I actually looked at the code people 
were proposing for returning null it struck me as completely the 
wrong way to do anything.

I get a very strong feeling of "We don't need no stinking exceptions" 
in this thread; and I don't think it's a rational response. I think 
they're a lot of programmers out there who don't like exceptions, 
never really understood them in the first place, and certainly don't 
feel comfortable with them now. I see this all the time in the 
students I teach, and one of the things I insist on in my classes is 
making sure my students use exceptions whether they want to or not.

I think they're a lot of programmers who don't want to have to think 
about how to handle exceptions. Returning null lets them ignore the 
problem and pretend it's gone away. All claimed benchmarks aside, 
that's its biggest attraction.

Throwing the exception is the right thing to do. It requires 
programmers to handle the case where the element isn't there. The 
reason checked exceptions exist is precisely because programmers 
can't be relied on to check error codes and return values. That's 
exactly what we're dealing with here. Whichever way the vote goes, 
this method will cause exceptions. The only question is whether these 
will be NoSuchChildExceptions that will be caught in a relevant catch 
block, or uncaught NullPointerExceptions that bring the whole program 
down.

+-----------------------+------------------------+-------------------+
| Elliotte Rusty Harold | elharo at metalab.unc.edu | Writer/Programmer |
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