如何在wifi網絡中測量延遲Java Java Android

Question

我正在開發一個移動應用程序，我需要一些參數來實現該算法，而且我不知道如何測量wifi網絡中的延遲。 有人說使用ping，但我不知道如何實現。

這是我正在學習的第一個問題。 謝謝。

Answer 1

請看看這個答案，這可能是您想要的

您可能想嘗試以下代碼示例來衡量執行某項操作的時間

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

這是我自己的實現，希望對您有所幫助：

/*
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;
}