如何在wifi网络中测量延迟Java Java Android

Question

I am developing a mobile app, I need some parameters to implement the algorithm, and I do not know how to measure latency in a wifi network. Some people says using ping, but I do not know how implement this.

This is my first question, I am learning. Thank you.

Answer 1

Please have a look at this answer it might be what you are after

you might want to try the following code sample to measure time to do something

String host = "172.16.0.2";
int timeout = 3000;
long beforeTime = System.currentTimeMillis();
reachable =  InetAddress.getByName(host).isReachable(timeout);
long afterTime = System.currentTimeMillis();
long timeDifference = afterTime - beforeTime;

Answer 2

Here is my own implementation, hope it helps:

/*
Returns the latency to a given server in mili-seconds by issuing a ping command.
system will issue NUMBER_OF_PACKTETS ICMP Echo Request packet each having size of 56 bytes
every second, and returns the avg latency of them.
Returns 0 when there is no connection
 */
public double getLatency(String ipAddress){
    String pingCommand = "/system/bin/ping -c " + NUMBER_OF_PACKTETS + " " + ipAddress;
    String inputLine = "";
    double avgRtt = 0;

    try {
        // execute the command on the environment interface
        Process process = Runtime.getRuntime().exec(pingCommand);
        // gets the input stream to get the output of the executed command
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(process.getInputStream()));

        inputLine = bufferedReader.readLine();
        while ((inputLine != null)) {
            if (inputLine.length() > 0 && inputLine.contains("avg")) {  // when we get to the last line of executed ping command
                break;
            }
            inputLine = bufferedReader.readLine();
        }
    }
    catch (IOException e){
        Log.v(DEBUG_TAG, "getLatency: EXCEPTION");
        e.printStackTrace();
    }

    // Extracting the average round trip time from the inputLine string
    String afterEqual = inputLine.substring(inputLine.indexOf("="), inputLine.length()).trim();
    String afterFirstSlash = afterEqual.substring(afterEqual.indexOf('/') + 1, afterEqual.length()).trim();
    String strAvgRtt = afterFirstSlash.substring(0, afterFirstSlash.indexOf('/'));
    avgRtt = Double.valueOf(strAvgRtt);

    return avgRtt;
}