Question

I need a function in Java to give me number of bytes needed to represent a given integer. When I pass 2 it should return 1, 400 -> 2, 822222 -> 3, etc.

@Edit: For now I’m stuck with this:

numOfBytes = Integer.highestOneBit(integer) / 8

Don’t know exactly what highestOneBit() does, but have also tried this:

numOfBytes = (int) (Math.floor(Math.log(integer)) + 1);

Which I found on some website.

Answer 1

static int byteSize(long x) {
    if (x < 0) throw new IllegalArgumentException();
    int s = 1;
    while (s < 8 && x >= (1L << (s * 8))) s++;
    return s;
}