A DESCRIPTION OF THE REQUEST :
the origin code is :

public static int numberOfLeadingZeros(int i) {
    // HD, Figure 5-6
    if (i == 0)
        return 32;
    int n = 1;
    if (i >>> 16 == 0) { n += 16; i <<= 16; }
    if (i >>> 24 == 0) { n += 8; i <<= 8; }
    if (i >>> 28 == 0) { n += 4; i <<= 4; }
    if (i >>> 30 == 0) { n += 2; i <<= 2; }
    n -= i >>> 31;
    return n;
}
I think it can be optimized ,should added following condition:

if (i < 0)
        return 0;
the fully optimized code is :

public static int numberOfLeadingZeros(int i) {
    // HD, Figure 5-6
    if (i == 0)
        return 32;
    if (i < 0)
        return 0;
    int n = 1;
    if (i >>> 16 == 0) { n += 16; i <<= 16; }
    if (i >>> 24 == 0) { n += 8; i <<= 8; }
    if (i >>> 28 == 0) { n += 4; i <<= 4; }
    if (i >>> 30 == 0) { n += 2; i <<= 2; }
    n -= i >>> 31;
    return n;
}

JUSTIFICATION :
In some condition, the intrinsic function may not called, the default java implementation will be run. then the original code will be slower than the optimized code.