XOM API for Processing XML with Java

[Elliotte Rusty Harold <elharo AT metalab.unc.edu>]

At 7:50 PM -0500 9/18/02, Bradley S. Huffman wrote:
> Attribute.java has a recursive constructor and JDK 1.4 complained about
> the signature of initCause in ParseException.java.

Thanks. The Attribute problem was easy enough to fix. I'm surprised 
the compiler didn't catch it. I added a unit test to catch this in 
the future.

The ParseException problem was easily found by switching to Java 1.4 
for the compile. What I don't understand is why the change was 
necessary. Shoudln't an overriding method be allowed to return a 
subclass of the return type of the original, overridden method? In 
this case, a ParseException is a Throwable, after all. Any idea 
what's going on here?

I agree it's a problem and needs to be fixed. I'm just trying to 
understand why it's a problem in the first place.
--

+-----------------------+------------------------+-------------------+
| Elliotte Rusty Harold | elharo AT metalab.unc.edu | Writer/Programmer |
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|          XML in a  Nutshell, 2nd Edition (O'Reilly, 2002)          |
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