问如何对4字节数组进行异或运算

EN

public static byte[] test(byte[] b1, byte[] b2, byte[] b3, byte[] b4) {
    if (b1.length > b2.length) {
        byte[] tmp = b2;
        b2 = b1;
        b1 = tmp;
    }
    for (int i = 0; i < b1.length; i++) {
        b2[i] ^= b1[i];
    }

    if (b2.length > b3.length) {
        byte[] tmp = b3;
        b3 = b2;
        b2 = tmp;
    }
    for (int i = 0; i < b2.length; i++) {
        b3[i] ^= b2[i];
    }

    if (b3.length > b4.length) {
        byte[] tmp = b4;
        b4 = b3;
        b3 = tmp;
    }
    for (int i = 0; i < b3.length; i++) {
        b4[i] ^= b3[i];
    }

    return b4;
}