Fixed a concurrent modification crash
Test: runtest -x packages/SystemUI/tests/src/com/android/systemui/settings/CurrentUserTrackerTest.java
Change-Id: I23261843b7366d3a66a795a41c61b7661f7ca3a6
Fixes: 38006784
diff --git a/packages/SystemUI/src/com/android/systemui/settings/CurrentUserTracker.java b/packages/SystemUI/src/com/android/systemui/settings/CurrentUserTracker.java
index 005206f..0b89dc1 100644
--- a/packages/SystemUI/src/com/android/systemui/settings/CurrentUserTracker.java
+++ b/packages/SystemUI/src/com/android/systemui/settings/CurrentUserTracker.java
@@ -22,6 +22,8 @@
import android.content.Intent;
import android.content.IntentFilter;
+import com.android.internal.annotations.VisibleForTesting;
+
import java.util.ArrayList;
import java.util.List;
import java.util.function.Consumer;
@@ -32,7 +34,12 @@
private Consumer<Integer> mCallback = this::onUserSwitched;
public CurrentUserTracker(Context context) {
- mUserReceiver = UserReceiver.getInstance(context);
+ this(UserReceiver.getInstance(context));
+ }
+
+ @VisibleForTesting
+ CurrentUserTracker(UserReceiver receiver) {
+ mUserReceiver = receiver;
}
public int getCurrentUserId() {
@@ -49,7 +56,8 @@
public abstract void onUserSwitched(int newUserId);
- private static class UserReceiver extends BroadcastReceiver {
+ @VisibleForTesting
+ static class UserReceiver extends BroadcastReceiver {
private static UserReceiver sInstance;
private Context mAppContext;
@@ -58,7 +66,8 @@
private List<Consumer<Integer>> mCallbacks = new ArrayList<>();
- private UserReceiver(Context context) {
+ @VisibleForTesting
+ UserReceiver(Context context) {
mAppContext = context.getApplicationContext();
}
@@ -105,8 +114,12 @@
private void notifyUserSwitched(int newUserId) {
if (mCurrentUserId != newUserId) {
mCurrentUserId = newUserId;
- for (Consumer<Integer> consumer : mCallbacks) {
- consumer.accept(newUserId);
+ List<Consumer<Integer>> callbacks = new ArrayList<>(mCallbacks);
+ for (Consumer<Integer> consumer : callbacks) {
+ // Accepting may modify this list
+ if (mCallbacks.contains(consumer)) {
+ consumer.accept(newUserId);
+ }
}
}
}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/settings/CurrentUserTrackerTest.java b/packages/SystemUI/tests/src/com/android/systemui/settings/CurrentUserTrackerTest.java
new file mode 100644
index 0000000..9e15a05
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/settings/CurrentUserTrackerTest.java
@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License
+ */
+
+package com.android.systemui.settings;
+
+import android.content.Intent;
+
+import com.android.systemui.SysuiTestCase;
+
+import org.junit.Before;
+import org.junit.Test;
+
+/**
+ * Testing functionality of the current user tracker
+ */
+public class CurrentUserTrackerTest extends SysuiTestCase {
+
+ private CurrentUserTracker mTracker;
+ private CurrentUserTracker.UserReceiver mReceiver;
+
+ @Before
+ public void setUp() {
+ mReceiver = new CurrentUserTracker.UserReceiver(getContext());
+ mTracker = new CurrentUserTracker(mReceiver) {
+ @Override
+ public void onUserSwitched(int newUserId) {
+ stopTracking();
+ }
+ };
+ }
+
+ @Test
+ public void testBroadCastDoesntCrashOnConcurrentModification() {
+ mTracker.startTracking();
+ CurrentUserTracker secondTracker = new CurrentUserTracker(mReceiver) {
+ @Override
+ public void onUserSwitched(int newUserId) {
+ stopTracking();
+ }
+ };
+ secondTracker.startTracking();
+ triggerUserSwitch();
+ }
+ /**
+ * Simulates a user switch event.
+ */
+ private void triggerUserSwitch() {
+ Intent intent = new Intent(Intent.ACTION_USER_SWITCHED);
+ intent.putExtra(Intent.EXTRA_USER_HANDLE, 1);
+ mReceiver.onReceive(getContext(), intent);
+ }
+}