Unsigned integer problem

Hi,
I have a problem of converting a CRand32 function from C to Java which was originally from IDA decompiler.
There's one thing that's troubling me for quite a long time which is the lack of unsigned types, I could not do operations such as byte shifting correctly and the end result I get is sometimes a negative number or larger than 4billion.
This CRand function should only generate 0 ~ 4billion.
Can anyone enlighten me in this? As it's the first time I am doing such things.
Here's the code I have from direct translation from C to Java :
    private transient long seed1, seed2, seed3; // In the code this is an unsigned int_32
    public final long CRand32__Random() {
     // assume the seed is already an unsigned long..
     seed1 = ((seed1 & 0xFFFFFFFE) << 12) ^
          (((seed1 << 13) ^ seed1) >> 19);
     seed2 = ((seed2 & 0xFFFFFFF8) << 4) ^
          (((seed2 << 2) ^ seed2) >> 25);
     seed3 = ((seed3 & 0xFFFFFFF0) << 17) ^
          (((seed3 << 3) ^ seed3) >> 11);
     return (seed1 ^ seed2 ^ seed3);
    }Thanks,
Edited by: LightPepsi on May 30, 2010 11:40 PM
Edited by: LightPepsi on May 30, 2010 11:40 PM

LightPepsi wrote:
That was the first thing which comes to my mind by changing >> to >>>, however the numbers generated are usually not within the range of an unsigned integer.
It can be sometimes a negative number or larger than 4 billion and thus making the randomizer inaccurate.One possibility is to use ints for the internal shifts, but create a long as
long unsignedValue = intValue & 0xFFFFFFFFL;for returning the number and possibly for any internal comparisons you need to make.
Winston

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