Tail recursive implementation of Binary Search in Java

BinarySearch.java

public static <T extends Comparable<? super T>> int rank(T[] seq, T key) {
    return rank(seq, key, 0, seq.length - 1);
}

public static <T extends Comparable<? super T>> int rank(T[] seq, T key, int lo, int hi) {
    if (lo > hi)
        return -1;

    int mid = lo + (hi - lo) / 2;
    int rel = key.compareTo(seq[mid]);
    if (rel > 0)
        return rank(seq, key, mid + 1, hi);
    else if (rel < 0)
        return rank(seq, key, lo, mid - 1);
    else
        return mid;
}

Of course Java doesn't support tail recursion but if it did, the provided code would be 100% tail recursive.