From 15bc894aae9192e26c35e0af22b5dbd2a5c30028 Mon Sep 17 00:00:00 2001
From: Robert Tsai <robtsai@google.com>
Date: Sat, 9 Jul 2011 23:57:22 -0700
Subject: Preserve invariant that sService is not null (although
 NfcAdapter.get() can return null)

Change-Id: I85fcbc5e79549835dac255ce614bd5d65d39fc25
---
 .../java/com/android/nfc_extras/NfcAdapterExtras.java   | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

(limited to 'nfc-extras')

diff --git a/nfc-extras/java/com/android/nfc_extras/NfcAdapterExtras.java b/nfc-extras/java/com/android/nfc_extras/NfcAdapterExtras.java
index e0c38b1..99cbb86 100644
--- a/nfc-extras/java/com/android/nfc_extras/NfcAdapterExtras.java
+++ b/nfc-extras/java/com/android/nfc_extras/NfcAdapterExtras.java
@@ -67,7 +67,11 @@ public final class NfcAdapterExtras {
 
     /** get service handles */
     private static void initService() {
-        sService = sAdapter.getNfcAdapterExtrasInterface();
+        final INfcAdapterExtras service = sAdapter.getNfcAdapterExtrasInterface();
+        if (service != null) {
+            // Leave stale rather than receive a null value.
+            sService = service;
+        }
     }
 
     /**
@@ -84,18 +88,19 @@ public final class NfcAdapterExtras {
             if (sSingleton == null) {
                 try {
                     sAdapter = adapter;
-                    sRouteOff = new CardEmulationRoute(CardEmulationRoute.ROUTE_OFF, null);
                     sSingleton = new NfcAdapterExtras();
                     sEmbeddedEe = new NfcExecutionEnvironment(sSingleton);
+                    sRouteOff = new CardEmulationRoute(CardEmulationRoute.ROUTE_OFF, null);
                     sRouteOnWhenScreenOn = new CardEmulationRoute(
                             CardEmulationRoute.ROUTE_ON_WHEN_SCREEN_ON, sEmbeddedEe);
                     initService();
                 } finally {
-                    if (sSingleton == null) {
-                        sService = null;
-                        sEmbeddedEe = null;
-                        sRouteOff = null;
+                    if (sService == null) {
                         sRouteOnWhenScreenOn = null;
+                        sRouteOff = null;
+                        sEmbeddedEe = null;
+                        sSingleton = null;
+                        sAdapter = null;
                     }
                 }
             }
-- 
cgit v1.1