byte[]&int&long

参考：http://blog.csdn.net/defonds/article/details/8782785

int 值和byte[]数组直接的转换：

 

public static int byteArrayToInt(byte[] b) {
    return   b[3] & 0xFF |
            (b[2] & 0xFF) << 8 |
            (b[1] & 0xFF) << 16 |
            (b[0] & 0xFF) << 24;
}

public static byte[] intToByteArray(int a) {
    return new byte[] {
        (byte) ((a >> 24) & 0xFF),
        (byte) ((a >> 16) & 0xFF),
        (byte) ((a >> 8) & 0xFF),
        (byte) (a & 0xFF)
    };
}