Hello,
I've filed
8012044: Give more information about self-suppression from
Throwable.addSuppressed
for this issue; it should be viewable on bugs.sun.com within a day or so.
Cheers,
-Joe
On 04/08/2013 04:54 PM, Steven Schlansker wrote:
Today I encountered "java.lang.IllegalArgumentException: Self-suppression not
permitted" from Throwable.addSuppressed.
My first surprise is that the try-with-resources block can throw this
exception; it is very confusing to have auto-generated code throw exceptions.
But beyond that, it is impossible to figure out *which* exception caused the
problem. If you have multiple resources acquired in the try-with-resources, it
could be any of them.
Would it be reasonable to change
public final synchronized void addSuppressed(Throwable exception) {
if (exception == this)
throw new IllegalArgumentException(SELF_SUPPRESSION_MESSAGE);
to
public final synchronized void addSuppressed(Throwable exception) {
if (exception == this)
throw new IllegalArgumentException(SELF_SUPPRESSION_MESSAGE, this);
so that when you get this exception it at least points to one of the throw
sites that actually caused the problem? Otherwise the only stack trace you
have is in auto-generated code and you are left scratching your head, wondering
where it came from. I believe this would increase the debuggability of the
try-with-resources construct and there's no immediately obvious downside.
I'm not the only one who was confused by this behavior:
http://stackoverflow.com/questions/12103126/what-on-earth-is-self-suppression-not-permitted-and-why-is-javac-generating-co
