things you should know about contributing:

1.  API changes require discussion, use cases, etc. Code comes later.
2.  Pull requests are great for small fixes for bugs, documentation, etc.
3.  Pull requests are not merged directly into the master branch.
4.  Code contributions require signing a Google CLA.

API changes
-----------

  `Take off your hat,' the King said to the Hatter.

  `It isn't mine,' said the Hatter.

  `Stolen!' the King exclaimed, turning to the jury, who
instantly made a memorandum of the fact.

  `I keep them to sell,' the Hatter added as an explanation;
`I've none of my own.  I'm a hatter.'

  Here the Queen put on her spectacles, and began staring at the
Hatter, who turned pale and fidgeted.

    future. (Previously, we sometimes removed such APIs after a deprecation
    period. The last release to remove non-`@Beta` APIs was Guava 21.0.) Even
    `@Deprecated` APIs will remain (again, unless they are `@Beta`). We have no
    plans to start removing things again, but officially, we're leaving our
    options open in case of surprises (like, say, a serious security problem).

  `Take off your hat,' the King said to the Hatter.

  `It isn't mine,' said the Hatter.

  `Stolen!' the King exclaimed, turning to the jury, who
instantly made a memorandum of the fact.

  `I keep them to sell,' the Hatter added as an explanation;
`I've none of my own.  I'm a hatter.'

  Here the Queen put on her spectacles, and began staring at the
Hatter, who turned pale and fidgeted.

<!--
Please read the contribution guidelines at
https://github.com/google/guava/wiki/HowToContribute#code-contributions
and
https://github.com/google/guava/blob/master/CONTRIBUTING.md
before sending a pull request.

We generally welcome PRs for fixing trivial bugs or typos, but please refrain
from sending a PR with significant changes unless explicitly requested.