<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:fitsSystemWindows="true"

    tools:context=".MainActivity">

    <WebView

        android:id="@+id/webview"

        android:layout_width="match_parent"

        android:layout_height="match_parent">

    </WebView>

</RelativeLayout>

 package com.webview.demo;

 import android.os.Bundle;

 import android.support.v7.app.AppCompatActivity;

 import android.webkit.WebView;

 import java.util.HashMap;

 import java.util.Map;

 public class MainActivity extends AppCompatActivity {

     private WebView webView ;

     private String webViewHeaderKey = "tokenId" ;

     private String webViewHeaderValue = "562142" ;

     private String url = "" ;

     @Override

     protected void onCreate(Bundle savedInstanceState) {

         super.onCreate(savedInstanceState);

         setContentView(R.layout.activity_main);

         webView = (WebView) findViewById( R.id.webview );

         if ( webViewHeaderValue != "" ){

             Map<String, String > map = new HashMap<String, String>() ;

             map.put( webViewHeaderKey , webViewHeaderValue ) ;

             webView.loadUrl( url  , map ) ;

         }else {

             webView.loadUrl( url ) ;

         }

     }

 }