How to convert names to numbers to implement sorting within groups?

Name numeric conversion realizes grouping sorting

When sorting users in groups, it is often necessary to convert the user name to numbers to ensure that the ordering between different groups is consistent. For example:

 <code>jack -> 75900张三-> 66640李四-> 54840</code>

How to implement this conversion and control the length of the number? Just sort the string directly, but if you need to convert it to a number, the following method is feasible.

Java's String.hashCode() method converts a string to an integer, but the result may be negative and has a longer length. To control the length, a modulus operation can be used:

 int hash = s.hashCode() % 100000;

where s is the user name string. This method ensures that the results are between 0 and 99999.

If you need to ensure that the result is a positive number, you can use bit operations:

 int hash = (s.hashCode() & 0x7fff) % 100000;

or

 int hash = (s.hashCode() % 100000) & 0x7fff;

Both methods can obtain positive integers between 0 and 99999.

Through the above method, you can convert the username to the number used for sorting and maintain a consistent sort in different groups. It should be noted that although hashCode() method usually provides good hash values, there is a possibility of conflict, so this method does not completely guarantee the uniqueness of the sorting results. If absolute uniqueness is required, other more complex algorithms need to be considered.

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