How to generate a unique hash code for string input in android…?

Question

I wanted to generate a unique hash code for a string in put in android. Is there any predefined library is there or we have to generate manually. Please any body if knows pl

Answer 1

Let's take a look at the stock hashCode() method:

public int hashCode() {
    int h = hash;
    if (h == 0 && count > 0) {
        for (int i = 0; i < count; i++) {
            h = 31 * h + charAt(i);
        }
        hash = h;
    }
    return h;
}

The block of code above comes from the java.lang.String class. As you can see it is a 32 bit hash code which fair enough if you are using it on a small scale of data. If you are looking for hash code with more than 32 bit, you might wanna checkout this link: http://www.javamex.com/tutorials/collections/strong_hash_code_implementation.shtml