java RC4 32 x,y

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public class RC4 {
private int[] maui8_sbox = new int[256];
private int x = 0;
private int y = 0;
private static int NUM = 256;

public RC4(int x, int y){
this.x = x;
this.y = y;
}

public void setKey(byte[] key, int _keyLen) {
int i = 0, j = 0;
int[] k = new int[256];
for (int s = 0; s < k.length; s++) {
k[s] = 0;
}
int tmp = 0;
for (i = 0; i < 256; i++) {
maui8_sbox[i] = i;
k[i] = key[i % _keyLen];
}
for (i = 0; i < 256; i++) {
j = (j + maui8_sbox[i] + k[i]) % 256;

// 交换s[i]和s[j]
tmp = maui8_sbox[i];
maui8_sbox[i] = maui8_sbox[j];
maui8_sbox[j] = tmp;
}
}

public byte[] _crypt(int x, int y, byte[] _data, int dataLen) {

int t = 0, i = 0;
for (i = 0; i < dataLen; i++) {
x = (x + 1) % 256;
y = (y + maui8_sbox[x]) % 256;
t = (maui8_sbox[x] + maui8_sbox[y]) % 256;
_data[i] ^= maui8_sbox[t];
}
return _data;
}

public byte[] encrypt(byte[] data, int dataLen) {
return _crypt(this.x, this.y, data, dataLen);
}

public byte[] decrypt(byte[] data, int dataLen) {
return _crypt(this.x, this.y, data, dataLen);
}

}