Re: Checked Exceptions

From:

Eric Sosman <esosman@ieee-dot-org.invalid>

Newsgroups:

comp.lang.java.programmer

Date:

Thu, 17 Dec 2009 09:59:10 -0500

Message-ID:

<hgdh16$bio$1@news.eternal-september.org>

On 12/15/2009 6:10 AM, Andreas Leitgeb wrote:

Arne Vajh??j<arne@vajhoej.dk> wrote:

Then, give us some way to handle more than one type of exception in the
same catch statement. "catch( FooException, BarException, WeirdException ex ) { }"

That has been proposed before. I guess it is OK.

I don't quite get it, what would be the actual compiletime type of "ex"
in the (here empty) catch-block.

It might be Throwable, or Exception, or maybe the least
common superclass of FooException/BarException/WeirdException.

Such a dodge might create additional complications of its
own, since the only methods and fields you could use with "ex"
would be those of the chosen superclass. Most (all?) of Java's
own exceptions inherit everything from Throwable so an "ex" type
of Throwable would be all right, but if FooException has a
getOffendingFoo() method you couldn't use it until you'd done a
downcast -- which, in a "combined catch," would probably need
instanceof or other reflective techniques clumsier than the
separate catch blocks being replaced.

--
Eric Sosman
esosman@ieee-dot-org.invalid