android - 使用 ping 列出本地网络上的设备

Question

我正在尝试创建一个列出本地网络上所有连接设备的函数。我所做的是将地址空间 xxx0 到 xxx255 的任何地址 ping 通，但它似乎无法正常工作。谁能以某种方式解释或扩展我的代码？我确实收到了电话 (10.0.0.17) 和默认网关 (10.0.0.138) 的回复。后者甚至不应该存在（事实上我不知道默认网关是什么但忽略它）。我错过了这台计算机的 IP。

public ArrayList<InetAddress> getConnectedDevices(String YourPhoneIPAddress) {
    ArrayList<InetAddress> ret = new ArrayList<InetAddress>();

    LoopCurrentIP = 0;

    //        String IPAddress = "";
    String[] myIPArray = YourPhoneIPAddress.split("\\.");
    InetAddress currentPingAddr;

    for (int i = 0; i <= 255; i++) {
        try {

            // build the next IP address
            currentPingAddr = InetAddress.getByName(myIPArray[0] + "." +
                    myIPArray[1] + "." +
                    myIPArray[2] + "." +
                    Integer.toString(LoopCurrentIP));

            // 50ms Timeout for the "ping"
            if (currentPingAddr.isReachable(50)) {
                if(currentPingAddr.getHostAddress() != YourPhoneIPAddress){
                    ret.add(currentPingAddr);

                }
            }
        } catch (UnknownHostException ex) {
        } catch (IOException ex) {
        }

        LoopCurrentIP++;
    }
    return ret;
}

Answer 1

这是稍微修改过的循环，应该可以解决问题（或者至少对我有用）；

try {
    NetworkInterface iFace = NetworkInterface
            .getByInetAddress(InetAddress.getByName(YourIPAddress));

    for (int i = 0; i <= 255; i++) {

        // build the next IP address
        String addr = YourIPAddress;
        addr = addr.substring(0, addr.lastIndexOf('.') + 1) + i;
        InetAddress pingAddr = InetAddress.getByName(addr);

        // 50ms Timeout for the "ping"
        if (pingAddr.isReachable(iFace, 200, 50)) {
            Log.d("PING", pingAddr.getHostAddress());
        }
    }
} catch (UnknownHostException ex) {
} catch (IOException ex) {
}