本文深入解析Android服务机制，包括应用程序服务（本地与远程）及系统服务（Java与本地）。详细介绍了服务的创建、绑定及通信过程，特别是Binder IPC机制的作用与实现方式。同时，文章还探讨了SystemServer如何初始化Java系统服务。
使用的版本：Android 2.3
Android服务分为两类：系统服务(由Framework提供)，应用程序服务。系统服务包括Java系统服务和本地系统服务，Java系统服务包含核心平台服务和硬件服务。应用程序服务分为本地服务和远程服务。
1.Android 应用程序服务
应用程序服务是后台服务程序，继承了Android SDK的Service类的类实例，没有UI界面，定期执行某些任务。这些大家都熟知了，启动方法有两种，startSrvice()和bindService()，具体过程就不多做阐述。这里强调一点，startService()创建服务的目的只是服务的启动和终止，而bindService()创建的服务是为了服务的远程控制。
Activity调用上述两种方法创建出服务，若该服务与创建服务的Activity运行在同一进程中，则把这种服务称为本地服务，本地服务只能在创建该服务的应用程序内部使用，当应用程序终止时，本地服务也一同终止。而远程服务与Activity运行在不同的进程中，Activity若想控制远程服务，必须使用IPC机制。在Binder IPC通信中，服务与Activity在交换数据时，需要经历Marshalling/Unmarshalling这一过程，为此就要使用AIDL(Android
Interface Definition Language，Android接口定义语言)。
1.1.本地服务
(1)Activity先通过bindService()方法尝试绑定LocalService，当绑定的服务不存在时，Android Framework会先生成LocalService。
(2)Android调用服务的onBind()回调方法，用来处理服务绑定，返回LocalBinder对象(继承自Binder类)。
(3)Android Framework调用服务客户端，即第一步的Activity的onServiceConnected(ComponentName,IBinder)回调方法，第二个方法接受LocalBinder对象。通过调用LocalBinder对象的getService()方法获取LocalService对象的应用。
(4)保存LocalService对象，完成本地服务绑定。
1.2远程服务
Android SDK会根据AIDL文件中定义的接口自动生成绑定远程服务所需要的代码。使用RemoteService的客户程序通过aidl生成的代码接口，调用RemoteService提供的函数，可以理解为RMI调用机制。在aidl文件中并不需要具体实现代码，实际的方法在RemoteService中。
(1)Binding Activity：请求RemoteService连接
(2)RemoteService服务：具体实现服务方法，并提供用于通信的Binder对象。
(3)Binding Activity：生成执行服务的Binder IPC的代理对象。
(4)Binding Activity：使用服务代理对象，调用其各种方法。
(5)Binder IPC：服务代理对象向服务Binder对象(stub)传递Binder IPC数据
(6)RemoteService服务：调用RemoteService服务的各种方法。
2.系统服务
系统服务分为本地系统服务和JAVA系统服务。其中本地系统服务使用C++编写，运行在Libraries层，主要包含Audio Flinger,Surface Flinger等。Java系统服务由SystemServer系统进程启动，它分为核心平台服务与硬件服务。
核心平台服务：Activity Manager Service,Window Manager Service,Package Manager Service
硬件服务：Alarm Manager Service,Connectivity Service,Location Service等
如应用程序若想使用Location Service，需要先调用getSystemService()函数，创建与Location Service相应的Local Manager对象。然后应用程序使用生成的Manager对象，调用Location Service提供的各种函数。
3 运行系统服务
init进程通过运行Media Server进程创建除Surface Flinger之外的本地系统服务，，Zygote通过System Server创建Surface Flinger和Java系统服务。
下面看一下Media Server的main()函数，在frameworks/base/media/mediaserver/main_mediaserver.cpp中
int main(int argc, char** argv)
{
sp<ProcessState> proc(ProcessState::self());
sp<IServiceManager> sm = defaultServiceManager();
LOGI("ServiceManager: %p", sm.get());
AudioFlinger::instantiate();
MediaPlayerService::instantiate();
CameraService::instantiate();
AudioPolicyService::instantiate();
ProcessState::self()->startThreadPool();
IPCThreadState::self()->joinThreadPool();
}
初始化各种本地服务对象。
系统服务与Framework中的其他模块通信，使用Binder IPC，系统服务这类服务提供者必须把相关信息注册到Context Manager中。
System Server是由Zygote进程生成，运行在Dalvik虚拟机的Java进程，用来运行多种java系统服务，还有Surface Flinger本地系统服务。在init.rc脚本中Zygote运行行带有"-start-system-server"选项时，该选项请求在Zygote中生成SystemServer。下面看一下SystemServer的main()方法。
frameworks/base/services/java/com/android/server/SystemServer.java
if (System.currentTimeMillis() < EARLIEST_SUPPORTED_TIME) {
// If a device's clock is before 1970 (before 0), a lot of
// APIs crash dealing with negative numbers, notably
// java.io.File#setLastModified, so instead we fake it and
// hope that time from cell towers or NTP fixes it
// shortly.
Slog.w(TAG, "System clock is before 1970; setting to 1970.");
SystemClock.setCurrentTimeMillis(EARLIEST_SUPPORTED_TIME);
}
if (SamplingProfilerIntegration.isEnabled()) {
SamplingProfilerIntegration.start();
timer = new Timer();
timer.schedule(new TimerTask() {
@Override
public void run() {
SamplingProfilerIntegration.writeSnapshot("system_server");
}
}, SNAPSHOT_INTERVAL, SNAPSHOT_INTERVAL);
}
// The system server has to run all of the time, so it needs to be
// as efficient as possible with its memory usage.
VMRuntime.getRuntime().setTargetHeapUtilization(0.8f);
System.loadLibrary("android_servers");
init1(args);最后一行init1()，通过JNI调用system_init()本地函数，system_init()函数的主要功能是生成并初始化本地系统服务Surface Flinger，在system_init()方法中frameworks/base/cmds/system_server/library/system_init.cpp中
extern "C" status_t system_init()
{
LOGI("Entered system_init()");
sp<ProcessState> proc(ProcessState::self());
sp<IServiceManager> sm = defaultServiceManager();
LOGI("ServiceManager: %p\n", sm.get());
sp<GrimReaper> grim = new GrimReaper();
sm->asBinder()->linkToDeath(grim, grim.get(), 0);
char propBuf[PROPERTY_VALUE_MAX];
property_get("system_init.startsurfaceflinger", propBuf, "1");
if (strcmp(propBuf, "1") == 0) {
// Start the SurfaceFlinger
SurfaceFlinger::instantiate();
}
// Start the sensor service
SensorService::instantiate();
// On the simulator, audioflinger et al don't get started the
// same way as on the device, and we need to start them here
if (!proc->supportsProcesses()) {
// Start the AudioFlinger
AudioFlinger::instantiate();
// Start the media playback service
MediaPlayerService::instantiate();
// Start the camera service
CameraService::instantiate();
// Start the audio policy service
AudioPolicyService::instantiate();
}
// And now start the Android runtime. We have to do this bit
// of nastiness because the Android runtime initialization requires
// some of the core system services to already be started.
// All other servers should just start the Android runtime at
// the beginning of their processes's main(), before calling
// the init function.
LOGI("System server: starting Android runtime.\n");
AndroidRuntime* runtime = AndroidRuntime::getRuntime();
LOGI("System server: starting Android services.\n");
runtime->callStatic("com/android/server/SystemServer", "init2");
// If running in our own process, just go into the thread
// pool. Otherwise, call the initialization finished
// func to let this process continue its initilization.
if (proc->supportsProcesses()) {
LOGI("System server: entering thread pool.\n");
ProcessState::self()->startThreadPool();
IPCThreadState::self()->joinThreadPool();
LOGI("System server: exiting thread pool.\n");
}
return NO_ERROR;
}init2()方法会创建ServerThread对象，而后启动它。ServerThread是一个Java线程，可以运行Android所有Java系统服务。
Android系统的服务通过调用ServiceManager类的addService()静态方法，将自身注册到Context Manager中，这里的ServiceManager是Context Manager的代理。
这里着重看一下
ProcessState::self()->startThreadPool();
IPCThreadState::self()->joinThreadPool();这两行代码。
void ProcessState::startThreadPool()
{
AutoMutex _l(mLock);
if (!mThreadPoolStarted) {
mThreadPoolStarted = true;
spawnPooledThread(true);
}
}
void IPCThreadState::joinThreadPool(bool isMain)
{
LOG_THREADPOOL("**** THREAD %p (PID %d) IS JOINING THE THREAD POOL\n", (void*)pthread_self(), getpid());
mOut.writeInt32(isMain ? BC_ENTER_LOOPER : BC_REGISTER_LOOPER);
// This thread may have been spawned by a thread that was in the background
// scheduling group, so first we will make sure it is in the default/foreground
// one to avoid performing an initial transaction in the background.
androidSetThreadSchedulingGroup(mMyThreadId, ANDROID_TGROUP_DEFAULT);
status_t result;
do {
int32_t cmd;
// When we've cleared the incoming command queue, process any pending derefs
if (mIn.dataPosition() >= mIn.dataSize()) {
size_t numPending = mPendingWeakDerefs.size();
if (numPending > 0) {
for (size_t i = 0; i < numPending; i++) {
RefBase::weakref_type* refs = mPendingWeakDerefs[i];
refs->decWeak(mProcess.get());
}
mPendingWeakDerefs.clear();
}
numPending = mPendingStrongDerefs.size();
if (numPending > 0) {
for (size_t i = 0; i < numPending; i++) {
BBinder* obj = mPendingStrongDerefs[i];
obj->decStrong(mProcess.get());
}
mPendingStrongDerefs.clear();
}
}
// now get the next command to be processed, waiting if necessary
result = talkWithDriver();
if (result >= NO_ERROR) {
size_t IN = mIn.dataAvail();
if (IN < sizeof(int32_t)) continue;
cmd = mIn.readInt32();
IF_LOG_COMMANDS() {
alog << "Processing top-level Command: "
<< getReturnString(cmd) << endl;
}
result = executeCommand(cmd);
}
// After executing the command, ensure that the thread is returned to the
// default cgroup before rejoining the pool. The driver takes care of
// restoring the priority, but doesn't do anything with cgroups so we
// need to take care of that here in userspace. Note that we do make
// sure to go in the foreground after executing a transaction, but
// there are other callbacks into user code that could have changed
// our group so we want to make absolutely sure it is put back.
androidSetThreadSchedulingGroup(mMyThreadId, ANDROID_TGROUP_DEFAULT);
// Let this thread exit the thread pool if it is no longer
// needed and it is not the main process thread.
if(result == TIMED_OUT && !isMain) {
break;
}
} while (result != -ECONNREFUSED && result != -EBADF);
LOG_THREADPOOL("**** THREAD %p (PID %d) IS LEAVING THE THREAD POOL err=%p\n",
(void*)pthread_self(), getpid(), (void*)result);
mOut.writeInt32(BC_EXIT_LOOPER);
talkWithDriver(false);
}这个是循环闭合框架，可以用
while(1){
talkWithDriver();
...
executeCommand();
}
形式来描述，这段代码放在init1()中是为了与Binder Driver通信。
ProcessState构造的时候，使用open_binder打开/driver/binder，并将句柄记录在mDriverFD,在ProcessState中并不使用这个句柄，真正使用这个Binder设备句柄的是IPCThreadState，所有关于Binder的操作放置在IPCThreadState中。
看一下frameworks/base/services/java/com/android/server/SystemServer.java
public void run() {
EventLog.writeEvent(EventLogTags.BOOT_PROGRESS_SYSTEM_RUN,
SystemClock.uptimeMillis());
Looper.prepare();
android.os.Process.setThreadPriority(
android.os.Process.THREAD_PRIORITY_FOREGROUND);
BinderInternal.disableBackgroundScheduling(true);
android.os.Process.setCanSelfBackground(false);
// Check whether we failed to shut down last time we tried.
{
final String shutdownAction = SystemProperties.get(
ShutdownThread.SHUTDOWN_ACTION_PROPERTY, "");
if (shutdownAction != null && shutdownAction.length() > 0) {
boolean reboot = (shutdownAction.charAt(0) == '1');
final String reason;
if (shutdownAction.length() > 1) {
reason = shutdownAction.substring(1, shutdownAction.length());
} else {
reason = null;
}
ShutdownThread.rebootOrShutdown(reboot, reason);
}
}
String factoryTestStr = SystemProperties.get("ro.factorytest");
int factoryTest = "".equals(factoryTestStr) ? SystemServer.FACTORY_TEST_OFF
: Integer.parseInt(factoryTestStr);
LightsService lights = null;
PowerManagerService power = null;
BatteryService battery = null;
ConnectivityService connectivity = null;
IPackageManager pm = null;
Context context = null;
WindowManagerService wm = null;
BluetoothService bluetooth = null;
BluetoothA2dpService bluetoothA2dp = null;
HeadsetObserver headset = null;
DockObserver dock = null;
UsbObserver usb = null;
UiModeManagerService uiMode = null;
RecognitionManagerService recognition = null;
ThrottleService throttle = null;
// Critical services...
try {
Slog.i(TAG, "Entropy Service");
ServiceManager.addService("entropy", new EntropyService());
Slog.i(TAG, "Power Manager");
power = new PowerManagerService();
ServiceManager.addService(Context.POWER_SERVICE, power);
Slog.i(TAG, "Activity Manager");
context = ActivityManagerService.main(factoryTest);
Slog.i(TAG, "Telephony Registry");
ServiceManager.addService("telephony.registry", new TelephonyRegistry(context));
AttributeCache.init(context);
Slog.i(TAG, "Package Manager");
pm = PackageManagerService.main(context,
factoryTest != SystemServer.FACTORY_TEST_OFF);
ActivityManagerService.setSystemProcess();
mContentResolver = context.getContentResolver();
// The AccountManager must come before the ContentService
try {
Slog.i(TAG, "Account Manager");
ServiceManager.addService(Context.ACCOUNT_SERVICE,
new AccountManagerService(context));
} catch (Throwable e) {
Slog.e(TAG, "Failure starting Account Manager", e);
}
Slog.i(TAG, "Content Manager");
ContentService.main(context,
factoryTest == SystemServer.FACTORY_TEST_LOW_LEVEL);
Slog.i(TAG, "System Content Providers");
ActivityManagerService.installSystemProviders();
Slog.i(TAG, "Battery Service");
battery = new BatteryService(context);
ServiceManager.addService("battery", battery);
Slog.i(TAG, "Lights Service");
lights = new LightsService(context);
Slog.i(TAG, "Vibrator Service");
ServiceManager.addService("vibrator", new VibratorService(context));
// only initialize the power service after we have started the
// lights service, content providers and the battery service.
power.init(context, lights, ActivityManagerService.getDefault(), battery);
Slog.i(TAG, "Alarm Manager");
AlarmManagerService alarm = new AlarmManagerService(context);
ServiceManager.addService(Context.ALARM_SERVICE, alarm);
Slog.i(TAG, "Init Watchdog");
Watchdog.getInstance().init(context, battery, power, alarm,
ActivityManagerService.self());
Slog.i(TAG, "Window Manager");
wm = WindowManagerService.main(context, power,
factoryTest != SystemServer.FACTORY_TEST_LOW_LEVEL);
ServiceManager.addService(Context.WINDOW_SERVICE, wm);
((ActivityManagerService)ServiceManager.getService("activity"))
.setWindowManager(wm);
// Skip Bluetooth if we have an emulator kernel
// TODO: Use a more reliable check to see if this product should
// support Bluetooth - see bug 988521
if (SystemProperties.get("ro.kernel.qemu").equals("1")) {
Slog.i(TAG, "Registering null Bluetooth Service (emulator)");
ServiceManager.addService(BluetoothAdapter.BLUETOOTH_SERVICE, null);
} else if (factoryTest == SystemServer.FACTORY_TEST_LOW_LEVEL) {
Slog.i(TAG, "Registering null Bluetooth Service (factory test)");
ServiceManager.addService(BluetoothAdapter.BLUETOOTH_SERVICE, null);
} else {
Slog.i(TAG, "Bluetooth Service");
bluetooth = new BluetoothService(context);
ServiceManager.addService(BluetoothAdapter.BLUETOOTH_SERVICE, bluetooth);
bluetooth.initAfterRegistration();
bluetoothA2dp = new BluetoothA2dpService(context, bluetooth);
ServiceManager.addService(BluetoothA2dpService.BLUETOOTH_A2DP_SERVICE,
bluetoothA2dp);
int bluetoothOn = Settings.Secure.getInt(mContentResolver,
Settings.Secure.BLUETOOTH_ON, 0);
if (bluetoothOn > 0) {
bluetooth.enable();
}
}
} catch (RuntimeException e) {
Slog.e("System", "Failure starting core service", e);
}
DevicePolicyManagerService devicePolicy = null;
StatusBarManagerService statusBar = null;
InputMethodManagerService imm = null;
AppWidgetService appWidget = null;
NotificationManagerService notification = null;
WallpaperManagerService wallpaper = null;
LocationManagerService location = null;
if (factoryTest != SystemServer.FACTORY_TEST_LOW_LEVEL) {
try {
Slog.i(TAG, "Device Policy");
devicePolicy = new DevicePolicyManagerService(context);
ServiceManager.addService(Context.DEVICE_POLICY_SERVICE, devicePolicy);
} catch (Throwable e) {
Slog.e(TAG, "Failure starting DevicePolicyService", e);
}
try {
Slog.i(TAG, "Status Bar");
statusBar = new StatusBarManagerService(context);
ServiceManager.addService(Context.STATUS_BAR_SERVICE, statusBar);
} catch (Throwable e) {
Slog.e(TAG, "Failure starting StatusBarManagerService", e);
}
try {
Slog.i(TAG, "Clipboard Service");
ServiceManager.addService(Context.CLIPBOARD_SERVICE,
new ClipboardService(context));
} catch (Throwable e) {
Slog.e(TAG, "Failure starting Clipboard Service", e);
}
try {
Slog.i(TAG, "Input Method Service");
imm = new InputMethodManagerService(context, statusBar);
ServiceManager.addService(Context.INPUT_METHOD_SERVICE, imm);
} catch (Throwable e) {
Slog.e(TAG, "Failure starting Input Manager Service", e);
}
try {
Slog.i(TAG, "NetStat Service");
ServiceManager.addService("netstat", new NetStatService(context));
} catch (Throwable e) {
Slog.e(TAG, "Failure starting NetStat Service", e);
}
try {
Slog.i(TAG, "NetworkManagement Service");
ServiceManager.addService(
Context.NETWORKMANAGEMENT_SERVICE,
NetworkManagementService.create(context));
} catch (Throwable e) {
Slog.e(TAG, "Failure starting NetworkManagement Service", e);
}
try {
Slog.i(TAG, "Connectivity Service");
connectivity = ConnectivityService.getInstance(context);
ServiceManager.addService(Context.CONNECTIVITY_SERVICE, connectivity);
} catch (Throwable e) {
Slog.e(TAG, "Failure starting Connectivity Service", e);
}
try {
Slog.i(TAG, "Throttle Service");
throttle = new ThrottleService(context);
ServiceManager.addService(
Context.THROTTLE_SERVICE, throttle);
} catch (Throwable e) {
Slog.e(TAG, "Failure starting ThrottleService", e);
}
try {
Slog.i(TAG, "Accessibility Manager");
ServiceManager.addService(Context.ACCESSIBILITY_SERVICE,
new AccessibilityManagerService(context));
} catch (Throwable e) {
Slog.e(TAG, "Failure starting Accessibility Manager", e);
}
try {
/*
* NotificationManagerService is dependant on MountService,
* (for media / usb notifications) so we must start MountService first.
*/
Slog.i(TAG, "Mount Service");
ServiceManager.addService("mount", new MountService(context));
} catch (Throwable e) {
Slog.e(TAG, "Failure starting Mount Service", e);
}
try {
Slog.i(TAG, "Notification Manager");
notification = new NotificationManagerService(context, statusBar, lights);
ServiceManager.addService(Context.NOTIFICATION_SERVICE, notification);
} catch (Throwable e) {
Slog.e(TAG, "Failure starting Notification Manager", e);
}
try {
Slog.i(TAG, "Device Storage Monitor");
ServiceManager.addService(DeviceStorageMonitorService.SERVICE,
new DeviceStorageMonitorService(context));
} catch (Throwable e) {
Slog.e(TAG, "Failure starting DeviceStorageMonitor service", e);
}
try {
Slog.i(TAG, "Location Manager");
location = new LocationManagerService(context);
ServiceManager.addService(Context.LOCATION_SERVICE, location);
} catch (Throwable e) {
Slog.e(TAG, "Failure starting Location Manager", e);
}
try {
Slog.i(TAG, "Search Service");
ServiceManager.addService(Context.SEARCH_SERVICE,
new SearchManagerService(context));
} catch (Throwable e) {
Slog.e(TAG, "Failure starting Search Service", e);
}
if (INCLUDE_DEMO) {
Slog.i(TAG, "Installing demo data...");
(new DemoThread(context)).start();
}
try {
Slog.i(TAG, "DropBox Service");
ServiceManager.addService(Context.DROPBOX_SERVICE,
new DropBoxManagerService(context, new File("/data/system/dropbox")));
} catch (Throwable e) {
Slog.e(TAG, "Failure starting DropBoxManagerService", e);
}
try {
Slog.i(TAG, "Wallpaper Service");
wallpaper = new WallpaperManagerService(context);
ServiceManager.addService(Context.WALLPAPER_SERVICE, wallpaper);
} catch (Throwable e) {
Slog.e(TAG, "Failure starting Wallpaper Service", e);
}
try {
Slog.i(TAG, "Audio Service");
ServiceManager.addService(Context.AUDIO_SERVICE, new AudioService(context));
} catch (Throwable e) {
Slog.e(TAG, "Failure starting Audio Service", e);
}
try {
Slog.i(TAG, "Headset Observer");
// Listen for wired headset changes
headset = new HeadsetObserver(context);
} catch (Throwable e) {
Slog.e(TAG, "Failure starting HeadsetObserver", e);
}
try {
Slog.i(TAG, "Dock Observer");
// Listen for dock station changes
dock = new DockObserver(context, power);
} catch (Throwable e) {
Slog.e(TAG, "Failure starting DockObserver", e);
}
try {
Slog.i(TAG, "USB Observer");
// Listen for USB changes
usb = new UsbObserver(context);
} catch (Throwable e) {
Slog.e(TAG, "Failure starting UsbObserver", e);
}
try {
Slog.i(TAG, "UI Mode Manager Service");
// Listen for UI mode changes
uiMode = new UiModeManagerService(context);
} catch (Throwable e) {
Slog.e(TAG, "Failure starting UiModeManagerService", e);
}
try {
Slog.i(TAG, "Backup Service");
ServiceManager.addService(Context.BACKUP_SERVICE,
new BackupManagerService(context));
} catch (Throwable e) {
Slog.e(TAG, "Failure starting Backup Service", e);
}
try {
Slog.i(TAG, "AppWidget Service");
appWidget = new AppWidgetService(context);
ServiceManager.addService(Context.APPWIDGET_SERVICE, appWidget);
} catch (Throwable e) {
Slog.e(TAG, "Failure starting AppWidget Service", e);
}
try {
Slog.i(TAG, "Recognition Service");
recognition = new RecognitionManagerService(context);
} catch (Throwable e) {
Slog.e(TAG, "Failure starting Recognition Service", e);
}
try {
Slog.i(TAG, "DiskStats Service");
ServiceManager.addService("diskstats", new DiskStatsService(context));
} catch (Throwable e) {
Slog.e(TAG, "Failure starting DiskStats Service", e);
}
}
// make sure the ADB_ENABLED setting value matches the secure property value
Settings.Secure.putInt(mContentResolver, Settings.Secure.ADB_ENABLED,
"1".equals(SystemProperties.get("persist.service.adb.enable")) ? 1 : 0);
// register observer to listen for settings changes
mContentResolver.registerContentObserver(Settings.Secure.getUriFor(Settings.Secure.ADB_ENABLED),
false, new AdbSettingsObserver());
// Before things start rolling, be sure we have decided whether
// we are in safe mode.
final boolean safeMode = wm.detectSafeMode();
if (safeMode) {
try {
ActivityManagerNative.getDefault().enterSafeMode();
// Post the safe mode state in the Zygote class
Zygote.systemInSafeMode = true;
// Disable the JIT for the system_server process
VMRuntime.getRuntime().disableJitCompilation();
} catch (RemoteException e) {
}
} else {
// Enable the JIT for the system_server process
VMRuntime.getRuntime().startJitCompilation();
}
// It is now time to start up the app processes...
if (devicePolicy != null) {
devicePolicy.systemReady();
}
if (notification != null) {
notification.systemReady();
}
if (statusBar != null) {
statusBar.systemReady();
}
wm.systemReady();
power.systemReady();
try {
pm.systemReady();
} catch (RemoteException e) {
}
// These are needed to propagate to the runnable below.
final StatusBarManagerService statusBarF = statusBar;
final BatteryService batteryF = battery;
final ConnectivityService connectivityF = connectivity;
final DockObserver dockF = dock;
final UsbObserver usbF = usb;
final ThrottleService throttleF = throttle;
final UiModeManagerService uiModeF = uiMode;
final AppWidgetService appWidgetF = appWidget;
final WallpaperManagerService wallpaperF = wallpaper;
final InputMethodManagerService immF = imm;
final RecognitionManagerService recognitionF = recognition;
final LocationManagerService locationF = location;
// We now tell the activity manager it is okay to run third party
// code. It will call back into us once it has gotten to the state
// where third party code can really run (but before it has actually
// started launching the initial applications), for us to complete our
// initialization.
((ActivityManagerService)ActivityManagerNative.getDefault())
.systemReady(new Runnable() {
public void run() {
Slog.i(TAG, "Making services ready");
if (statusBarF != null) statusBarF.systemReady2();
if (batteryF != null) batteryF.systemReady();
if (connectivityF != null) connectivityF.systemReady();
if (dockF != null) dockF.systemReady();
if (usbF != null) usbF.systemReady();
if (uiModeF != null) uiModeF.systemReady();
if (recognitionF != null) recognitionF.systemReady();
Watchdog.getInstance().start();
// It is now okay to let the various system services start their
// third party code...
if (appWidgetF != null) appWidgetF.systemReady(safeMode);
if (wallpaperF != null) wallpaperF.systemReady();
if (immF != null) immF.systemReady();
if (locationF != null) locationF.systemReady();
if (throttleF != null) throttleF.systemReady();
}
});
// For debug builds, log event loop stalls to dropbox for analysis.
if (StrictMode.conditionallyEnableDebugLogging()) {
Slog.i(TAG, "Enabled StrictMode for system server main thread.");
}
Looper.loop();
Slog.d(TAG, "System ServerThread is exiting!");
}
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