On May 3, 2012, at 2:30 PM, Julius Davies [via Apache Commons] wrote:
> > So if we agree that the Encoders that exist are thread-safe (as we've
> > defined it) and that they should be in general, then I plan to treat them
> > that way in Lucene.
>
>
> I guess you're saying you'll do this:
>
> Pattern #1: save some memory, lose some thread safety
> ---
> public class MyClass {
> private static Encoder E = new Encoder();
>
> public void myMethod() {
> // need to encode or decode for some reason:
> E.encode(stuff);
> }
> }
> ---
Sure. There's the possibility of a static block configuring the encoder too.
Of course, this same pattern could be realized without using 'static', but
static is a concise way of demonstrating a happens-before relationshipo in
example code. Another would be a volatile instance variable that is only set
after the encoder is configured. And I assume myMethod() is going to be
invoked concurrently on the same MyClass instance by multiple threads.
>
> Instead of this?
>
>
> Pattern #2: lose some memory (temporarily to hold encode table), gain
> some thread safety:
> ---
> public class MyClass {
> public void myMethod() {
> // need to encode or decode for some reason:
> new Encoder().encode(stuff);
> }
> }
> ---
>
Right; not that.
>
> Base64 definitely requires pattern #2, but the others appear to be
> less complex, and might be okay.
I've seen people say that Encoders should be made to be threadsafe and
documented as such. I've not heard a dissenting opinion to this proposal. So
if Base64 can't work in pattern #1, I suggest this be rectified. All the
phonetic encoders appear to be thread-safe already.
> Interesting dilemma. As an (inactive) codec developer, I prefer
> pattern #2 because it means less work for us, but, at the same time,
> there is no way to force developers to go with pattern #2 (even if we
> documented developers might not read it) and so coding defensively
> over here in case developers pick approach #1 could result in less
> work for us in the long run (fewer weird race condition bugs filed in
> Jira?).
>
>
> Mostly talking to myself here.
>
~ David
-----
Author: http://www.packtpub.com/apache-solr-3-enterprise-search-server/book
--
View this message in context:
http://apache-commons.680414.n4.nabble.com/Thread-safety-of-Commons-Codec-Encoder-tp4600956p4606799.html
Sent from the Commons - User mailing list archive at Nabble.com.
