Fixed a concurrent modification crash (fc9af34b) · Commits · e / os / android_frameworks_base

packages/SystemUI/src/com/android/systemui/settings/CurrentUserTracker.java

+18 −5

Original line number	Diff line number	Diff line
		@@ -22,6 +22,8 @@ import android.content.Context;
		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 @@ public abstract class CurrentUserTracker {
		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 class CurrentUserTracker {

		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 @@ public abstract class CurrentUserTracker {

		private List<Consumer<Integer>> mCallbacks = new ArrayList<>();

		private UserReceiver(Context context) {
		@VisibleForTesting
		UserReceiver(Context context) {
		mAppContext = context.getApplicationContext();
		}

		@@ -105,10 +114,14 @@ public abstract class CurrentUserTracker {
		private void notifyUserSwitched(int newUserId) {
		if (mCurrentUserId != newUserId) {
		mCurrentUserId = newUserId;
		for (Consumer<Integer> consumer : mCallbacks) {
		List<Consumer<Integer>> callbacks = new ArrayList<>(mCallbacks);
		for (Consumer<Integer> consumer : callbacks) {
		// Accepting may modify this list
		if (mCallbacks.contains(consumer)) {
		consumer.accept(newUserId);
		}
		}
		}
		}
		}
		}

packages/SystemUI/tests/src/com/android/systemui/settings/CurrentUserTrackerTest.java

0 → 100644

+65 −0

Original line number	Diff line number	Diff line
		/*
		* 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);
		}
		}