программное обеспечение для связи с сервером NTP на android

Хочу синхронизировать время на нескольких смартфонах. Есть программа для физического эксперимента где необходимо точное и одинаковое время на трех смартфонах с точностью до тысячных или более. Нашел реализацию на https://stackoverflow.com/questions/925191/java-ntp-client :

public class NTPClient {

  private static final String SERVER_NAME = "pool.ntp.org";

  private volatile TimeInfo timeInfo;
  private volatile Long offset;

  public static void main() throws Exception {

    NTPUDPClient client = new NTPUDPClient();
    client.setDefaultTimeout(10_000);

    InetAddress inetAddress = InetAddress.getByName(SERVER_NAME);
    TimeInfo timeInfo = client.getTime(inetAddress);
    timeInfo.computeDetails();

    if (timeInfo.getOffset() != null) {
        this.timeInfo = timeInfo;
        this.offset = timeInfo.getOffset();
    }

    // This system NTP time
    TimeStamp systemNtpTime = TimeStamp.getCurrentTime();
    System.out.println("System time:\t" + systemNtpTime + "  " + systemNtpTime.toDateString());

    // Calculate the remote server NTP time
    long currentTime = System.currentTimeMillis();
    TimeStamp atomicNtpTime = TimeStamp.getNtpTime(currentTime + offset).getTime()

    System.out.println("Atomic time:\t" + atomicNtpTime + "  " + atomicNtpTime.toDateString());
  }

  public boolean isComputed()
  {
    return timeInfo != null && offset != null;
  }
}

В функцию public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) вставил это:

client.setDefaultTimeout(10_000);

    InetAddress inetAddress = InetAddress.getByName(SERVER_NAME);//<--- тут программа вылетает 
    TimeInfo timeInfo = client.getTime(inetAddress);
    timeInfo.computeDetails();
    if (timeInfo.getOffset() != null) {
        this.timeInfo = timeInfo;
        this.offset = timeInfo.getOffset();
    }

Программа при запуске вылетает в указанном месте. Скажите, пожалуйста кто знает, почему программа вылетает в указанном месте? Хотя в Idea все работает.

Сообщения об ошибках:

04/25 22:01:25: Launching 'app' on OnePlus ONEPLUS A3010.
App restart successful without requiring a re-install.
$ adb shell am start -n "com.example.datarecorderapp/com.example.datarecorderapp.MainActivity" -a android.intent.action.MAIN -c android.intent.category.LAUNCHER -D
Waiting for application to come online: com.example.datarecorderapp.test | com.example.datarecorderapp
Waiting for application to come online: com.example.datarecorderapp.test | com.example.datarecorderapp
Connected to process 25675 on device 'oneplus-oneplus_a3010-511f6b9d'.
Waiting for application to come online: com.example.datarecorderapp.test | com.example.datarecorderapp
Connecting to com.example.datarecorderapp
Connected to the target VM, address: 'localhost:62082', transport: 'socket'
Capturing and displaying logcat messages from application. This behavior can be disabled in the "Logcat output" section of the "Debugger" settings page.
I/datarecorderap: Late-enabling -Xcheck:jni
I/datarecorderap: The ClassLoaderContext is a special shared library.
W/ActivityThread: Application com.example.datarecorderapp is waiting for the debugger on port 8100...
I/System.out: Sending WAIT chunk
I/System.out: Debugger has connected
    waiting for debugger to settle...
I/chatty: uid=10204(com.example.datarecorderapp) identical 5 lines
I/System.out: waiting for debugger to settle...
I/System.out: debugger has settled (1394)
I/Perf: Connecting to perf service.
W/datarecorderap: Accessing hidden method Landroid/graphics/drawable/Drawable;->getOpticalInsets()Landroid/graphics/Insets; (light greylist, linking)
    Accessing hidden field Landroid/graphics/Insets;->left:I (light greylist, linking)
    Accessing hidden field Landroid/graphics/Insets;->right:I (light greylist, linking)
    Accessing hidden field Landroid/graphics/Insets;->top:I (light greylist, linking)
    Accessing hidden field Landroid/graphics/Insets;->bottom:I (light greylist, linking)
W/datarecorderap: Accessing hidden field Landroid/view/WindowInsets;->CONSUMED:Landroid/view/WindowInsets; (light greylist, reflection)
W/datarecorderap: Accessing hidden method Landroid/view/View;->getAccessibilityDelegate()Landroid/view/View$AccessibilityDelegate; (light greylist, linking)
W/datarecorderap: Accessing hidden method Landroid/view/View;->computeFitSystemWindows(Landroid/graphics/Rect;Landroid/graphics/Rect;)Z (light greylist, reflection)
W/datarecorderap: Accessing hidden method Landroid/view/ViewGroup;->makeOptionalFitsSystemWindows()V (light greylist, reflection)
W/datarecorderap: Accessing hidden method Landroid/graphics/FontFamily;-><init>()V (light greylist, reflection)
    Accessing hidden method Landroid/graphics/FontFamily;->addFontFromAssetManager(Landroid/content/res/AssetManager;Ljava/lang/String;IZIII[Landroid/graphics/fonts/FontVariationAxis;)Z (light greylist, reflection)
    Accessing hidden method Landroid/graphics/FontFamily;->addFontFromBuffer(Ljava/nio/ByteBuffer;I[Landroid/graphics/fonts/FontVariationAxis;II)Z (light greylist, reflection)
    Accessing hidden method Landroid/graphics/FontFamily;->freeze()Z (light greylist, reflection)
W/datarecorderap: Accessing hidden method Landroid/graphics/FontFamily;->abortCreation()V (light greylist, reflection)
    Accessing hidden method Landroid/graphics/Typeface;->createFromFamiliesWithDefault([Landroid/graphics/FontFamily;Ljava/lang/String;II)Landroid/graphics/Typeface; (light greylist, reflection)
D/AndroidRuntime: Shutting down VM
E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.datarecorderapp, PID: 25675
    android.os.NetworkOnMainThreadException
        at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1513)
        at java.net.Inet6AddressImpl.lookupHostByName(Inet6AddressImpl.java:117)
        at java.net.Inet6AddressImpl.lookupAllHostAddr(Inet6AddressImpl.java:105)
        at java.net.InetAddress.getByName(InetAddress.java:1108)
        at com.example.datarecorderapp.FragmentMainWindow.onViewCreated(FragmentMainWindow.java:166)
        at androidx.fragment.app.FragmentStateManager.createView(FragmentStateManager.java:322)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1185)
        at androidx.fragment.app.FragmentManager.addAddedFragments(FragmentManager.java:2222)
        at androidx.fragment.app.FragmentManager.executeOpsTogether(FragmentManager.java:1995)
        at androidx.fragment.app.FragmentManager.removeRedundantOperationsAndExecute(FragmentManager.java:1951)
        at androidx.fragment.app.FragmentManager.execPendingActions(FragmentManager.java:1847)
        at androidx.fragment.app.FragmentManager.dispatchStateChange(FragmentManager.java:2621)
        at androidx.fragment.app.FragmentManager.dispatchActivityCreated(FragmentManager.java:2569)
        at androidx.fragment.app.Fragment.performActivityCreated(Fragment.java:2722)
        at androidx.fragment.app.FragmentStateManager.activityCreated(FragmentStateManager.java:336)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1186)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1354)
        at androidx.fragment.app.FragmentManager.moveFragmentToExpectedState(FragmentManager.java:1432)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1495)
        at androidx.fragment.app.FragmentManager.dispatchStateChange(FragmentManager.java:2617)
        at androidx.fragment.app.FragmentManager.dispatchActivityCreated(FragmentManager.java:2569)
        at androidx.fragment.app.FragmentController.dispatchActivityCreated(FragmentController.java:247)
        at androidx.fragment.app.FragmentActivity.onStart(FragmentActivity.java:541)
        at androidx.appcompat.app.AppCompatActivity.onStart(AppCompatActivity.java:210)
        at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1470)
        at android.app.Activity.performStart(Activity.java:7170)
        at android.app.ActivityThread.handleStartActivity(ActivityThread.java:3061)
        at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:180)
        at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:165)
        at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:142)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:70)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1906)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:193)
        at android.app.ActivityThread.main(ActivityThread.java:6863)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:537)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
W/OPDiagnose: getService:OPDiagnoseService NULL
D/OSTracker: OS Event: crash
D/AbstractTracker: Event success
Disconnected from the target VM, address: 'localhost:62082', transport: 'socket'