Option 3 seems okay to me. ~ Bhupesh
_______________________________________________________ Bhupesh Chawda E: bhup...@datatorrent.com | Twitter: @bhupeshsc www.datatorrent.com | apex.apache.org On Mon, Apr 24, 2017 at 7:53 PM, Vlad Rozov <v.ro...@datatorrent.com> wrote: > +1 for option 3. > > Thank you, > > Vlad > > > On 4/23/17 16:25, Ananth G wrote: > >> Hello All, >> >> Apologies if it is a repost as the earlier email did not seem to go >> through. >> >> I have run into a dilemma and would like to know what our policy is to >> deal >> with the following situation. >> >> As part of the implementation for Kudu Input operator ( >> https://issues.apache.org/jira/browse/APEXMALHAR-2472) , I will be using >> Antlr4 as the parser tool to parse a line of string as an SQL equivalent >> statement to represent the set of tuples that will be streamed out of Kudu >> store to the downstream operators. >> >> I will post the design once a few things are finalised in a separate >> mailing thread and this mail is more about Checkstyle and Auto generated >> code from tools like Antlr4. >> >> The design involves in writing a grammar file and let the maven tool >> generate the parser and related code as .java files as part of the build >> process. We only keep maintaining the grammar “.g4” file as part of the >> repository checkins as Kudu functionality evolves. However this brings me >> to the situation wherein the check style fails for the classes that are >> autogenerated. Following are the three options that I think we have and >> would like to get thoughts on what is the best way to go forward. >> >> *Option 1:* We let the autogenerated code generate code in the >> "target/generated-sources” path. This is the default for the maven antler >> plugin. This however does not pass check style maven plugin as check style >> plugin does check styles for auto-generated code as well. The fix for this >> is to modify check style plugin to only look at “src/“ folder paths as >> opposed “compiled sources”. This works from a build perspective but the >> drawback is that IDEs will not include the “target/generated-sources” for >> class resolution. IDEs do have plugins to resolve this error code but >> might >> be considered irksome by the developer community. >> >> *Option 2:* We let Antlr4 code-gen to generate code in the Kudu package >> path and of course checkstlye would fail this as well. The fix is to let >> Checktyle include a “excludes” pattern and make check style ignore all >> java >> files that represent a pattern of files generated by the Antlr4 code-gen >> tool. There is still an issue that remains to be resolved even if this >> approach is approved by the community. The issue is the tool generates a >> couple of “.token” files that are always placed in the root class path and >> not under the package structure which will pollute the sanity a bit. I am >> still working on this bit as this needs to be resolved. >> >> *Option 3:* Perhaps the ideal is to let a separate module for kudu from >> the >> top level to resolve all of the issues ideally ( i.e. token files are >> generated in the kudu module root along with the java sources in the >> correct package structure ) and I guess that is a separate discussion that >> Thomas/Vlad and others are planning to take up as a separate thread in the >> mailing list. >> >> Could you please let me what you think is the ideal path to pursue ( or if >> there are other alternatives for the use case above ) >> >> Regards, >> Ananth >> >> >