Fix the bug of out of index of the the shard index

[zhengrenjie]

No description provided.

[ou-taku14]

There is the hash function in String: hash = s[0]*31^(n-1) + s[1]*31^(n-2) + ... + s[n-1](here s[n] is the nth character in the string). I have a problem why the string'hashcode is negative.

[ou-taku14]

And I have another problem: the original hash function provides uniform distribution of hash across the range of integers, and does the new hash function which is the function |hashCode()| have the same property? Because the number of the calculated hash value o will be small.

[jovany-wang]

And I have another problem: the original hash function provides uniform distribution of hash across the range of integers, and does the new hash function which is the function |hashCode()| have the same property? Because the number of the calculated hash value o will be small.

Yes, you are right. But it's not a matter because 0/2^32 is almost 0.