Add precondition checks

[digitalbuddha]

This ticket is a bit open ended. Add precondition checks where necessary.

[scottroemeschke]

did you want to do inline, or with some kind of Preconditions class with some methods to resuse everywhere? I see the one in the cache from Guava, but if you wanted to use that everywhere you'd want to move it to the base artifiact I'm guessing.

[digitalbuddha]

Guava one preferably. I'm pretty sure everything depends on Cache since it's a dependency of Store. Internally we use Guava but to keep method count down we don't have access here. I'm OK copying in other guava preconditions if they are needed.

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On Jan 9, 2017 12:27 PM, "Scott Meschke" ***@***.***> wrote: did you want to do inline, or with some kind of Preconditions class with some methods to resuse everywhere? I see the one in the cache from Guava, but if you wanted to use that everywhere you'd want to move it to the base artifiact I'm guessing. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#41 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AEUX3GSA542xzmlkzaK-k9BF69jAgoJiks5rQm4UgaJpZM4LeGUt> .

[brianPlummer]

#56