Unsigned int - problem translating c++ function to java

Question

OK so here's the deal:
I'm writing a client for a internet comunicator in java (J2ME to be precise). Unfortunately i have specs for this comunicator's protocol for c++ programing. The first problem I ran to is: I have to calculate a hash for a password so it doesn't go plain text on the network. The function in c++ that does this is:
int getPasswordHash(char *password, int seed){
    unsigned int x=0, y=0, z=0;
    char *pwd = password;
    y = seed;
    for (x = 0; *password; password++) {
     x = (x & 0xffffff00) | *password;
     y ^= x;
     y += x;
     x <<= 8;
     y ^= x;
     x <<= 8;
     y -= x;
     x <<= 8;
     y ^= x;
     z = y & 0x1f;
     y = (y << z) | (y >> (32 - z));
    cout << "Hash for \"" << pwd << "\" with seed \"" << seed << "\": " << y << "\n";
    return y;
}My translation to java goes:
public int getPasswordHash(String password, int seed){
    long x = 0, y = 0, z = 0;
    int tmp = 0;
    String pwd = password;
    y = seed;
    for (x = 0; x < password.length(); x++){
        tmp = (int)x;
        x = x | password.charAt(tmp);
        y ^= x;
        y = uintadd(y, x);
        x <<= 8;
        y ^= x;
        x <<= 8;
        y = uintsubst(y, x);
        x <<= 8;
        y ^= x;
        z = y & 0x1f;
        y = (y << z) | (y >> (32 - z));
        x = tmp;
    System.out.println("Hash for \""+ pwd + "\" with seed \"" + seed + "\": " + y);
    return (int)y;
public long uintadd (long x, long y){
    long xL = x & 0xffffffffL;
    long yL = y & 0xffffffffL;
    long sumL = xL + yL;
    long sum = (sumL & 0xffffffffL);
    return sum;
public long uintsubst (long x, long y){
    long xL = x & 0xffffffffL;
    long yL = y & 0xffffffffL;
    long sumL = xL - yL;
    long sum = (sumL & 0xffffffffL);
    return sum;
}So I use the uintadd and uintsubst to add and substract values that should be unsigned int. Every operation works exactly like in c++ (I've checked) until this point:y = (y << z) | (y >> (32 - z));and to be exact (y << z) This doesn't turn out like in c++ so the whole function doesn't return the right vaule. I know it's because doing a bit operation on a unsigned int in c++ is different in than in java because unsigned variables have totally different bit values than signed ones. The question is: how to work this out. I managed to do aritmetic operations working but I have no idea how to deal with this. Any help would be great.

Answer 1

I'm by no means the expert with this, but I'm going
to guess that this would work...
y = ((y << z) & 0xffffffffL) | (y >> (32 - z));
thus... to zero out the right shifted 1's before the
orWOW WOW WOW it totaly works thanks alot bsampieri !!