How to get Date and Time from online servers in your Android App?

In this video, it shows how one can fetch date and time from an online server in your Android App. Fetching or synchronizingtime from an online server may give more accurate results in case the system’s (OS) date and time is manipulated by some other Apps.

In this tutorial it uses NIST server to fetch the date and time. List of NIST servers can be found at: https://tf.nist.gov/tf-cgi/servers.cgi

In this code, global server provided by NIST, time.nist.gov, is used.

I hope you like this video. For any questions, suggestions or appreciation please contact us at: https://programmerworld.co/contact/ or email at: programmerworld1990@gmail.com

Complete source code:

package com.programmerworld.getdateandtimeonlineserver;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.os.StrictMode;
import android.view.View;
import android.widget.TextView;

import org.apache.commons.net.time.TimeTCPClient;

import java.io.IOException;

public class MainActivity extends AppCompatActivity {

    private TextView textView;
    private TimeTCPClient timeTCPClient;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        textView = findViewById(R.id.textView);

        StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
        StrictMode.setThreadPolicy(policy);

        timeTCPClient = new TimeTCPClient();
    }

    public void buttonFetch(View view){
        try {
            timeTCPClient.connect("time.nist.gov");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void buttonDisplay(View view){
        try {
            textView.setText(timeTCPClient.getDate().toString().substring(0, 20));
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.396" />

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="86dp"
        android:layout_marginTop="55dp"
        android:onClick="buttonFetch"
        android:text="Fetch Date from Server"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/button2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="86dp"
        android:layout_marginTop="71dp"
        android:onClick="buttonDisplay"
        android:text="Display Date and Time"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/button" />

</androidx.constraintlayout.widget.ConstraintLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.programmerworld.getdateandtimeonlineserver">

    <uses-permission android:name="android.permission.INTERNET"/>

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.GetDateAndTimeOnlineServer">
        <activity
            android:name=".MainActivity"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

plugins {
    id 'com.android.application'
}

android {
    compileSdk 31

    defaultConfig {
        applicationId "com.programmerworld.getdateandtimeonlineserver"
        minSdk 31
        targetSdk 31
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
}

dependencies {

    implementation 'androidx.appcompat:appcompat:1.4.1'
    implementation 'com.google.android.material:material:1.5.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.1.3'
    testImplementation 'junit:junit:4.13.2'
    androidTestImplementation 'androidx.test.ext:junit:1.1.3'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0'

    implementation 'commons-net:commons-net:3.6'
}