BitCount() Issue

Perhaps I'm misunderstanding the purpose of BitCount. I thought that it would return the number of bits needed to represent the current value held in a variable. Is this correct?

I'm trying to write a simulator but certain registers can't be over 24 bits or 48 bits. Hm, well, closest I have to that are Integers and Longs.

Here's the function checking:

Code:

---

        public void SetValue(long val){
               
                System.out.println(" bitCount: " + Long.bitCount(val));
               
                if(Long.bitCount(val) > bitNum){
                        System.out.println("Too many bits! bitCount: " + Long.bitCount(val) + " > " + bitNum);
                }
                else{
                        value = val;
                }
        }

---

And here's my output:

Code:

---

//In the test program I set the initial value to 3. The max number of bits
//is also 3, for testing simplicity.

bitCount: 2
Reg Value: 3

Input really big number:
25

bitCount: 3
Reg Value: 25

---

Nevermind--I found my answer elsewhere.

So that, it's better to post your solution over here. It may helpful for others as well. And also if you've solve the problem then please mark the thread solved.