Ping Application in Android

Ping Application in Android

I have used following code to ping.

public String ping(String url) {
    String str = "";
    try {
        Process process = Runtime.getRuntime().exec(
                "/system/bin/ping -c 8 " + url);
        BufferedReader reader = new BufferedReader(new InputStreamReader(
                process.getInputStream()));
        int i;
        char[] buffer = new char[4096];
        StringBuffer output = new StringBuffer();
        while ((i = reader.read(buffer)) > 0)
            output.append(buffer, 0, i);
        reader.close();

        // body.append(output.toString()+"\n");
        str = output.toString();
        // Log.d(TAG, str);
    } catch (IOException e) {
        // body.append("Error\n");
        e.printStackTrace();
    }
    return str;
}

Here in the url, you need to pass the address, on which you want to ping.

Android App for ping not work

As @dhiku said it is heavily discouraged but you can run this piece of code to allow all kinds of threads. Run in your onCreate() after setting the content:

    //allow all threading policies
    if(Build.VERSION.SDK_INT >9){
        StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
        StrictMode.setThreadPolicy(policy);
    }

Android ICMP ping

Afaik, sending ICMP ECHO requests needs root (i.e. the app that does it needs to be setuid) - and that's not currently possible in "stock" Android (hell, even the InetAddress#isReachable() method in Android is a joke that doesn't work according to spec).

A very basic example using /usr/bin/ping & Process - reading the ping results, using an AsyncTask:

public class PingActivity extends Activity {
    PingTask mTask;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }

    @Override
    protected void onResume() {
        super.onResume();
        mTask = new PingTask();
        // Ping the host "android.com"
        mTask.execute("android.com");
    }

    @Override
    protected void onPause() {
        super.onPause();
        mTask.stop();
    }

    class PingTask extends AsyncTask<String, Void, Void> {
        PipedOutputStream mPOut;
        PipedInputStream mPIn;
        LineNumberReader mReader;
        Process mProcess;
        TextView mText = (TextView) findViewById(R.id.text);
        @Override
        protected void onPreExecute() {
            mPOut = new PipedOutputStream();
            try {
                mPIn = new PipedInputStream(mPOut);
                mReader = new LineNumberReader(new InputStreamReader(mPIn));
            } catch (IOException e) {
                cancel(true);
            }

        }

        public void stop() {
            Process p = mProcess;
            if (p != null) {
                p.destroy();
            }
            cancel(true);
        }

        @Override
        protected Void doInBackground(String... params) {
            try {
                mProcess = new ProcessBuilder()
                    .command("/system/bin/ping", params[0])
                    .redirectErrorStream(true)
                    .start();

                try {
                    InputStream in = mProcess.getInputStream();
                    OutputStream out = mProcess.getOutputStream();
                    byte[] buffer = new byte[1024];
                    int count;

                    // in -> buffer -> mPOut -> mReader -> 1 line of ping information to parse
                    while ((count = in.read(buffer)) != -1) {
                        mPOut.write(buffer, 0, count);
                        publishProgress();
                    }
                    out.close();
                    in.close();
                    mPOut.close();
                    mPIn.close();
                } finally {
                    mProcess.destroy();
                    mProcess = null;
                }
            } catch (IOException e) {
            }
            return null;
        }
        @Override
        protected void onProgressUpdate(Void... values) {
            try {
                // Is a line ready to read from the "ping" command?
                while (mReader.ready()) {
                    // This just displays the output, you should typically parse it I guess.
                    mText.setText(mReader.readLine());
                }
            } catch (IOException t) {
            }
        }
    }
}

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