目录
- 10.9 ActiveServices.bumpServiceExecutingLocked
- 10.9.1 发送SERVICE_TIMEOUT_MSG
- 10.10 ActivityThread.scheduleCreateService
- 10.11 ApplicationThread.scheduleCreateService()
- 10.12 ActivityManagerService.serviceDoneExecuting()
- 10.13 ActiveServices.serviceDoneExecutingLocked()
- 10.14 serviceDoneExecutingLocked
- 11. 0 sendServiceArgsLocked
》
10.9 ActiveServices.bumpServiceExecutingLocked
private final void bumpServiceExecutingLocked(ServiceRecord r, boolean fg, String why) { if (DEBUG_SERVICE) Slog.v(TAG_SERVICE, ">>> EXECUTING " + why + " of " + r + " in app " + r.app); else if (DEBUG_SERVICE_EXECUTING) Slog.v(TAG_SERVICE_EXECUTING, ">>> EXECUTING " + why + " of " + r.shortName); long now = SystemClock.uptimeMillis(); 【executeNesting 记录前台次数，第一次为0，fg是启动前台还是后台服务】 if (r.executeNesting == 0) { r.executeFg = fg; ProcessStats.ServiceState stracker = r.getTracker(); if (stracker != null) { stracker.setExecuting(true, mAm.mProcessStats.getMemFactorLocked(), now); } if (r.app != null) { r.app.executingServices.add(r); r.app.execServicesFg |= fg; if (r.app.executingServices.size() == 1) { scheduleServiceTimeoutLocked(r.app); 【10.9.1 发送SERVICE_TIMEOUT_MSG】 } } } else if (r.app != null && fg && !r.app.execServicesFg) { r.app.execServicesFg = true; scheduleServiceTimeoutLocked(r.app); } r.executeFg |= fg; r.executeNesting++; r.executingStart = now; }
10.9.1 发送SERVICE_TIMEOUT_MSG
void scheduleServiceTimeoutLocked(ProcessRecord proc) { if (proc.executingServices.size() == 0 || proc.thread == null) { return; } long now = SystemClock.uptimeMillis(); Message msg = mAm.mHandler.obtainMessage( ActivityManagerService.SERVICE_TIMEOUT_MSG); msg.obj = proc; 【发送SERVICE_TIMEOUT_MSG消息】 mAm.mHandler.sendMessageAtTime(msg, proc.execServicesFg ? (now+SERVICE_TIMEOUT) : (now+ SERVICE_BACKGROUND_TIMEOUT)); }
前台服务 SERVICE_TIMEOUT是20s
后台服务 SERVICE_BACKGROUND_TIMEOUT是200s
如果超过上面时间，没有移除SERVICE_TIMEOUT_MSG消息，就会弹出ANR消息。
10.10 ActivityThread.scheduleCreateService
app.thread.scheduleCreateService(r, r.serviceInfo,mAm.compatibilityInfoForPackageLocked(r.serviceInfo.applicationInfo),app.repProcState);
其实调用的方法是ApplicationThreadProxy中的scheduleCreateService()，代码写在ApplicationThreadNative.java中
public final void scheduleCreateService(IBinder token, ServiceInfo info, CompatibilityInfo compatInfo, int processState) throws RemoteException { Parcel data = Parcel.obtain(); data.writeInterfaceToken(IApplicationThread.descriptor); data.writeStrongBinder(token); info.writeToParcel(data, 0); compatInfo.writeToParcel(data, 0); data.writeInt(processState); try { 【是不是很熟悉，，，binder....然后到了ApplicationThreadNative的onTransact()】 mRemote.transact(SCHEDULE_CREATE_SERVICE_TRANSACTION, data, null, IBinder.FLAG_ONEWAY); } catch (TransactionTooLargeException e) { Log.e("CREATE_SERVICE", "Binder failure starting service; service=" + info); throw e; } data.recycle(); }
mRemote.transact()这是不是很熟悉啊，，参考前面《》中ActivityManagerProxy、ActivityManagerNative和ActivityManagerService的关系，这里省略
最后运行到了ApplicationThread.scheduleCreateService()
10.11 ApplicationThread.scheduleCreateService()
ApplicationThread是在ActivityThread.java中
public final void scheduleCreateService(IBinder token, ServiceInfo info, CompatibilityInfo compatInfo, int processState) { updateProcessState(processState, false); CreateServiceData s = new CreateServiceData(); s.token = token; s.info = info; s.compatInfo = compatInfo; 【发送CREATE_SERVICE消息】 sendMessage(H.CREATE_SERVICE, s); } case CREATE_SERVICE: Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "serviceCreate"); 【handleCreateService】 handleCreateService((CreateServiceData)msg.obj); Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER); break; private void handleCreateService(CreateServiceData data) { // If we are getting ready to gc after going to the background, well // we are back active so skip it. unscheduleGcIdler(); ..... try { if (localLOGV) Slog.v(TAG, "Creating service " + data.info.name); ContextImpl context = ContextImpl.createAppContext(this, packageInfo); context.setOuterContext(service); Application app = packageInfo.makeApplication(false, mInstrumentation); service.attach(context, this, data.info.name, data.token, app, ActivityManagerNative.getDefault()); 【service.onCreate()创建】 service.onCreate(); mServices.put(data.token, service); try { 【10.12 这里调用的是ActivityManagerService.serviceDoneExecuting()此时出传入type=SERVICE_DONE_EXECUTING_ANON 】 ActivityManagerNative.getDefault().serviceDoneExecuting( data.token, SERVICE_DONE_EXECUTING_ANON, 0, 0); } catch (RemoteException e) { // nothing to do. } } catch (Exception e) { if (!mInstrumentation.onException(service, e)) { throw new RuntimeException( "Unable to create service " + data.info.name + ": " + e.toString(), e); } } }
10.12 ActivityManagerService.serviceDoneExecuting()
public void serviceDoneExecuting(IBinder token, int type, int startId, int res) { synchronized(this) { if (!(token instanceof ServiceRecord)) { Slog.e(TAG, "serviceDoneExecuting: Invalid service token=" + token); throw new IllegalArgumentException("Invalid service token"); } 【10.13 serviceDoneExecutingLocked】 mServices.serviceDoneExecutingLocked((ServiceRecord)token, type, startId, res); } }
10.13 ActiveServices.serviceDoneExecutingLocked()
在onCreate时候传入的type是SERVICE_DONE_EXECUTING_ANON，上面可以看到。
void serviceDoneExecutingLocked(ServiceRecord r, int type, int startId, int res) { boolean inDestroying = mDestroyingServices.contains(r); if (r != null) { if (type == ActivityThread.SERVICE_DONE_EXECUTING_START) { ..... } else if (type == ActivityThread.SERVICE_DONE_EXECUTING_STOP) { ...... } final long origId = Binder.clearCallingIdentity(); // 10.14 type 都不符合上面条件，因此直接走这里serviceDoneExecutingLocked serviceDoneExecutingLocked(r, inDestroying, inDestroying); Binder.restoreCallingIdentity(origId); } else { Slog.w(TAG, "Done executing unknown service from pid " + Binder.getCallingPid()); } }
10.14 serviceDoneExecutingLocked
private void serviceDoneExecutingLocked(ServiceRecord r, boolean inDestroying, boolean finishing) { r.executeNesting--; if (r.executeNesting <= 0) { if (r.app != null) { if (DEBUG_SERVICE) Slog.v(TAG_SERVICE, "Nesting at 0 of " + r.shortName); r.app.execServicesFg = false; r.app.executingServices.remove(r); if (r.app.executingServices.size() == 0) { if (DEBUG_SERVICE || DEBUG_SERVICE_EXECUTING) Slog.v(TAG_SERVICE_EXECUTING, "No more executingServices of " + r.shortName); 【移除超时SERVICE_TIMEOUT_MSG消息，否则就会ANR】 mAm.mHandler.removeMessages(ActivityManagerService.SERVICE_TIMEOUT_MSG, r.app); } else if (r.executeFg) { // Need to re-evaluate whether the app still needs to be in the foreground. for (int i=r.app.executingServices.size()-1; i>=0; i--) { if (r.app.executingServices.valueAt(i).executeFg) { r.app.execServicesFg = true; break; } } } ...... } }
如果没有移除超时消息SERVICE_TIMEOUT_MSG，就会ANR。
onCreate()执行完后，接着是前面提到的sendServiceArgsLocked()，我们继续
11. 0 sendServiceArgsLocked
服务进入onStartCommand()
private final void sendServiceArgsLocked(ServiceRecord r, boolean execInFg,
boolean oomAdjusted) throws TransactionTooLargeException {
final int N = r.pendingStarts.size();
if (N == 0) {
return;
}
while (r.pendingStarts.size() > 0) {
Exception caughtException = null;
ServiceRecord.StartItem si;
try {
si = r.pendingStarts.remove(0);
if (DEBUG_SERVICE) Slog.v(TAG_SERVICE, "Sending arguments to: "
+ r + " " + r.intent + " args=" + si.intent);
if (si.intent == null && N > 1) {
// If somehow we got a dummy null intent in the middle,
// then skip it. DO NOT skip a null intent when it is
// the only one in the list -- this is to support the
// onStartCommand(null) case.
continue;
}
si.deliveredTime = SystemClock.uptimeMillis();
r.deliveredStarts.add(si);
si.deliveryCount++;
if (si.neededGrants != null) {
mAm.grantUriPermissionUncheckedFromIntentLocked(si.neededGrants,
si.getUriPermissionsLocked());
}
【和 10.9 ActiveServices.bumpServiceExecutingLocked 发送SERVICE_TIMEOUT_MSG用来判断是否ANR，一样】
bumpServiceExecutingLocked(r, execInFg, "start");
if (!oomAdjusted) {
oomAdjusted = true;
mAm.updateOomAdjLocked(r.app);
}
int flags = 0;
if (si.deliveryCount > 1) {
flags |= Service.START_FLAG_RETRY;
}
if (si.doneExecutingCount > 0) {
flags |= Service.START_FLAG_REDELIVERY;
}
【启动onStartCommand，这个和启动onCreate()的路径都一样，这里都不在重复】
r.app.thread.scheduleServiceArgs(r, si.taskRemoved, si.id, flags, si.intent);
} catch (TransactionTooLargeException e) {
if (DEBUG_SERVICE) Slog.v(TAG_SERVICE, "Transaction too large: intent="
+ si.intent);
caughtException = e;
} catch (RemoteException e) {
// Remote process gone... we'll let the normal cleanup take care of this.
if (DEBUG_SERVICE) Slog.v(TAG_SERVICE, "Crashed while sending args: " + r);
caughtException = e;
} catch (Exception e) {
Slog.w(TAG, "Unexpected exception", e);
caughtException = e;
}
if (caughtException != null) {
// Keep nesting count correct
final boolean inDestroying = mDestroyingServices.contains(r);
serviceDoneExecutingLocked(r, inDestroying, inDestroying);
if (caughtException instanceof TransactionTooLargeException) {
throw (TransactionTooLargeException)caughtException;
}
break;
}
}
}
启动onStartCommand()和onCreate()流程差不多，这个就不再重复。流程很长，细节部分都丢了。
总结
1、在流程中，我们看到了在ActivityThread.java中初始化了Looper.prepareMainLooper()和开启了Looper.loop()
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太久了，略过吧