对接C++socket打包发送与解析,打包解包一律使用网络字节序(大端)java该怎么实现?

我这边java对接C++遇到些问题，首先是对方提供的文档没有例子，demo也是c++源码的，对方一直强调打包、网络字节序(大端)，这块不是很懂，希望有大佬联系解决 

	
static void MakeHead(WORD cmd, char * buf, ULONG& len, UINT val=0)
{
    cmd = htons(cmd);
    unsigned long ulIndex = 0;
    /*<!-------------- Group Code ------------------->*/
    buf[ulIndex++] = (CHAR)0xDF;   
    short wn = ::htons(0x01);
    /*<!-------------- Command ID ------------------->*/
    // 第一个参数是目标地址，第二个参数是原地址，第三个参数是复制多少字节
    ::memcpy(&buf[ulIndex], &cmd, 2); ulIndex+=2; 
    /*<!---------------- Version -------------------->*/
    buf[ulIndex++] = 1; 
    /*<!------------- Command Flag ------------------>*/
    ulIndex+=4; 
    /*<!------------- Total Segment ----------------->*/
    wn = ::htons(0x01);
    //std::cout << "(network) total segment=" << wn << std::endl;
    ::memcpy(&buf[ulIndex], &wn, 2); ulIndex+=2;
    /*<!-------------- Sub Segment ------------------>*/
    wn = ::htons(0x01);
    //std::cout << "(network) sub segment=" << wn << std::endl;
    ::memcpy(&buf[ulIndex], &wn, 2); ulIndex+=2;
 
    /*<!------------- Segment  Flag ----------------->*/
    ulIndex+=2;
    /*<!--------------- Reserved1 ------------------->*/
    ulIndex+=2;
    /*<!--------------- Reserved2 ------------------->*/
    ulIndex+=4;
    /*<!---------------- Payload -------------------->*/
    if (cmd == htons(0x0A09))
    {
        val = htonl(val);
        memcpy(&buf[ulIndex], &val, 4); ulIndex+=4;
    }
    //输出字符a的地址
    len = ulIndex;
}