hashCode implementation in Java String [duplicate]

Question

Just curious, in String's hashCode implementation what is the reason behind extra references creation in a hashCode implementation (v 1.8.0_65):

public int hashCode() {
    int h = hash;
    if (h == 0 && value.length > 0) {
        char val[] = value;

        for (int i = 0; i < value.length; i++) {
            h = 31 * h + val[i];
        }
        hash = h;
    }
    return h;
}

Taking into consideration that value is final and created in constructor only (i.e. threadsafe) why do we need variable val[] reference here?

I.e. will this work:

public int hashCode() {
    if (hash == 0 && value.length > 0) {
        int h = 0;
        for (int i = 0; i < value.length; i++) {
            h = 31 * h + value[i];
        }
        hash = h;
    }
    return hash;
}

?

In addition to copying values from heap to stack to speed things up it is also about race conditions described in comments by @zapl. Which was not obvious to me before his comment.

Answer 1

It seems like the intent is to put hash and the value handle explicitly on the stack