How to check internet connection in Android

First In androidmanifest.xml file give the permission of internet given below. 
<uses-permission android:name="android.permission.INTERNET"></uses-permission> 
And Internet Connection code given below. This are simply create one Internetconnection() function. 


private boolean InternetConnection() {
ConnectivityManager conMgr = (ConnectivityManager) getSystemService (Context.CONNECTIVITY_SERVICE);
if (conMgr.getActiveNetworkInfo() != null
&& conMgr.getActiveNetworkInfo().isAvailable()
&& conMgr.getActiveNetworkInfo().isConnected()) {
return true;
} else {
Toast.makeText(getApplicationContext(),"Please check your Internet connection, You are now seeing the cached version.",Toast.LENGTH_LONG).show();
return false;
}
} 

you must have internet and access_network_state permissions in androidmanifest.xml

You need to add below 2 lines into AndroidManifest.xml file

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

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="com.company"
          android:versionCode="1" android:versionName="1.0">
  <application android:icon="@drawable/icon" android:label="@string/app_name"
               android:debuggable="true">
    <activity android:label="@string/app_name" android:name="BannerExample">
      <intent-filter>
        <action android:name="android.intent.action.MAIN"/>
        <category android:name="android.intent.category.LAUNCHER"/>
      </intent-filter>
    </activity>
    <activity android:name="com.google.ads.AdActivity"
              android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|uiMode|screenSize|smallestScreenSize"/>
  </application>
  <uses-permission android:name="android.permission.INTERNET"/>
  <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
</manifest>