But it means that other functions that call SerializableFunctions must now declare exceptions, right? If yes, this is incompatible.
On Sun, Oct 14, 2018 at 1:37 AM Romain Manni-Bucau <rmannibu...@gmail.com> wrote: > No, only parameter types and return type is used to lookup methods. > > Romain Manni-Bucau > @rmannibucau <https://twitter.com/rmannibucau> | Blog > <https://rmannibucau.metawerx.net/> | Old Blog > <http://rmannibucau.wordpress.com> | Github > <https://github.com/rmannibucau> | LinkedIn > <https://www.linkedin.com/in/rmannibucau> | Book > <https://www.packtpub.com/application-development/java-ee-8-high-performance> > > > Le dim. 14 oct. 2018 à 09:45, Reuven Lax <re...@google.com> a écrit : > >> I've run into this problem before as well. Doesn't changing the signature >> involve a backwards-incompatible change though? >> >> On Wed, Oct 3, 2018 at 5:11 PM Jeff Klukas <jklu...@mozilla.com> wrote: >> >>> I'm working on https://issues.apache.org/jira/browse/BEAM-5638 to add >>> exception handling options to single message transforms in the Java SDK. >>> >>> MapElements' via() method is overloaded to accept either a >>> SimpleFunction, a SerializableFunction, or a Contextful, all of which are >>> ultimately stored as a Contextful where the mapping functionis expected to >>> have signature: >>> >>> OutputT apply(InputT element, Context c) throws Exception; >>> >>> So Contextful.Fn allows throwing checked exceptions, but neither >>> SerializableFunction nor SimpleFunction do. The user-provided function >>> has to satisfy the more restrictive signature: >>> >>> OutputT apply(InputT input); >>> >>> Is there background about why we allow arbitrary checked exceptions to >>> be thrown in one case but not the other two? Could we consider expanding >>> SerializableFunction and SimpleFunction to the following?: >>> >>> OutputT apply(InputT input) throws Exception; >>> >>> This would, for example, simplify the implementation of ParseJsons and >>> AsJsons, where we have to catch an IOException in MapElements#via only to >>> rethrow as RuntimeException. >>> >>
