Reflect review comments

- Check ACCESS_NETWORK_STATE permission to avoid crash
- Create a normal Socket when Wi-Fi network isn't
  available or the permission isn't available
- Add null checkings

1 files changed, 49 insertions, 15 deletions

diff --git a/sdl_android/src/main/java/com/smartdevicelink/transport/utl/WiFiSocketFactory.java b/sdl_android/src/main/java/com/smartdevicelink/transport/utl/WiFiSocketFactory.java
index 31449cf57..b35070d89 100644
--- a/sdl_android/src/main/java/com/smartdevicelink/transport/utl/WiFiSocketFactory.java
+++ b/sdl_android/src/main/java/com/smartdevicelink/transport/utl/WiFiSocketFactory.java
@@ -1,7 +1,9 @@
 package com.smartdevicelink.transport.utl;
 
+import android.Manifest;
 import android.annotation.TargetApi;
 import android.content.Context;
+import android.content.pm.PackageManager;
 import android.net.ConnectivityManager;
 import android.net.Network;
 import android.net.NetworkCapabilities;
@@ -10,53 +12,85 @@ import android.os.Build;
 import java.io.IOException;
 import java.net.Socket;
 
+import javax.net.SocketFactory;
+
 import static com.smartdevicelink.util.NativeLogTool.logInfo;
 
 public class WiFiSocketFactory {
     /**
-     * Creates a TCP socket which is bound to Wi-Fi network (for Android 5+)
+     * Try to create a TCP socket which is bound to Wi-Fi network (for Android 5+)
      *
-     * On Android 5 and later, this method returns a Socket which is always bound to a Wi-Fi
-     * network. If the phone is not connected to a Wi-Fi network, this method throws an IOException.
-     * Prior to Android 5, this method simply creates a Socket equivalent to "new Socket();".
+     * On Android 5 and later, this method tries to create a Socket instance which is bound to a
+     * Wi-Fi network. If the phone is not connected to a Wi-Fi network, or the app lacks
+     * required permission (ACCESS_NETWORK_STATE), then this method simply creates a Socket instance
+     * with "new Socket();".
      *
-     * @return a Socket instance bound to Wi-Fi network.
+     * @return a Socket instance, preferably bound to a Wi-Fi network
      */
-    public static Socket createSocket(Context context) throws IOException {
+    public static Socket createSocket(Context context) {
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
             Socket socket = createWiFiSocket(context);
-            if (socket == null) {
-                logInfo("Cannot find Wi-Fi network, aborting socket creation.");
-                throw new IOException("The phone is not connected to Wi-Fi network");
+            if (socket != null) {
+                logInfo("Created a Socket bound to Wi-Fi network");
+                return socket;
             }
-            return socket;
-        } else {
-            return new Socket();
         }
+
+        return new Socket();
     }
 
     @TargetApi(Build.VERSION_CODES.LOLLIPOP)
     private static Socket createWiFiSocket(Context context) {
+        PackageManager pm = context.getPackageManager();
+        if (pm == null) {
+            logInfo("PackageManager isn't available.");
+            return null;
+        }
+        // getAllNetworks() and getNetworkCapabilities() require ACCESS_NETWORK_STATE
+        if (pm.checkPermission(Manifest.permission.ACCESS_NETWORK_STATE, context.getPackageName()) != PackageManager.PERMISSION_GRANTED) {
+            logInfo("Router service doesn't have ACCESS_NETWORK_STATE permission. It cannot bind a TCP transport to Wi-Fi network.");
+            return null;
+        }
+
         ConnectivityManager connMan = (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);
-        // requires ACCESS_NETWORK_STATE permission
+        if (connMan == null) {
+            logInfo("ConnectivityManager isn't available.");
+            return null;
+        }
+
         Network[] allNetworks = connMan.getAllNetworks();
+        if (allNetworks == null) {
+            logInfo("Failed to acquire a list of networks.");
+            return null;
+        }
 
         // Samsung Galaxy S9 (with Android 8.0.0) provides two `Network` instances which have
         // TRANSPORT_WIFI capability. The first one throws an IOException upon creating a Socket,
         // and the second one actually works. To support such case, here we iterate over all
         // `Network` instances until we can create a Socket.
         for (Network network : allNetworks) {
-            // requires ACCESS_NETWORK_STATE permission
+            if (network == null) {
+                continue;
+            }
+
             NetworkCapabilities capabilities = connMan.getNetworkCapabilities(network);
+            if (capabilities == null) {
+                continue;
+            }
+
             if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)) {
                 try {
-                    return network.getSocketFactory().createSocket();
+                    SocketFactory factory = network.getSocketFactory();
+                    if (factory != null) {
+                        return factory.createSocket();
+                    }
                 } catch (IOException e) {
                     logInfo("IOException during socket creation (ignored): " + e.getMessage());
                 }
             }
         }
 
+        logInfo("Cannot find Wi-Fi network to bind a TCP transport.");
         return null;
     }
 }