Okay, so, PR#314[1] updates the formatter plugin in the master branch to fix an issue with the previous formatter, which stopped formatting javadocs. Unfortunately, the newer plugin also declares that it requires Maven 3.5.0 or later to run. This is probably not true, but it does seem to be enforced by some versions of Maven, which refuse to execute the plugin.
So, we have a two choices: 1. Revert the change, and wait for a possible upstream fix which will let us do builds with earlier versions of Maven, or 2. Accept it as is, and just do builds in the master branch with the latest and greatest version of Maven, 3.5.0. 2a. Configure the maven-enforcer-plugin in Accumulo's builds to require Maven 3.5.0 or later to solidify the decision, or 2b. Leave Accumulo's minimum build version at 3.2.5, as it is today, and hope the formatter plugin backs off on its requirements in a newer version, which we will update to when available so builds won't fail when using 3.2.5 or 3.3.9. Personally, I'm inclined to prefer option 2b. Maven 3.5.0 is pretty nice to use anyway. I'm loving the colorized output. And also, we need something to keep the formatting correct during development in the master branch, and the earlier versions either have broken javadoc formatting, or use a very antiquated Eclipse formatter that is terrible at line-wrapping. Given the choices, I don't think requiring builds to be done with 3.5.0 is all that bad. 2b is a decent option over 2a, because you can still add '-P!autoformat' to skip formatting if you're stuck with an older version of Maven. And, if anybody is interested, I already updated Jenkins jobs on builds.apache.org to use Maven 3.5.0, so they should be fine, regardless. [1]: https://github.com/apache/accumulo/pull/314/commits/41ec3e2a248e22037e200edfcae65c08eafab687
