StrictMode分析Registion-StrictMode原理(4)

4. Registion的泄漏问题

这里的Registion主要有两种，分别是Service、BroadCastReceiver:

4.2 检测时机

这里先补充一个前置知识点，stopService的流程:

Context.stopSerivce  -> ActivityThread.STOP_SERVICE -> ActivityThread.scheduleContextCleanup() -> LoadApk.removeContextRegistrations

我们需要的检测时机，在removeContextRegistrations，这里面用到了两个成员变量:

//根据context,来存储当前的广播以及广播分发器 
private final ArrayMap<Context, ArrayMap<BroadcastReceiver, ReceiverDispatcher>> mReceivers
        = new ArrayMap<>();
//根据context，来存储service以及service的分发器
private final ArrayMap<Context, ArrayMap<ServiceConnection, LoadedApk.ServiceDispatcher>> mServices
        = new ArrayMap<>();

 public void removeContextRegistrations(Context context,
            String who, String what) {
    
  			//是否开启了注册泄漏
        final boolean reportRegistrationLeaks = StrictMode.vmRegistrationLeaksEnabled();
        synchronized (mReceivers) {
    
          //拿到与当前context相同的map
            ArrayMap<BroadcastReceiver, LoadedApk.ReceiverDispatcher> rmap =
                    mReceivers.remove(context);
            if (rmap != null) {
    
   
              //分析receiver的泄漏
                for (int i = 0; i < rmap.size(); i++) {
    
                    LoadedApk.ReceiverDispatcher rd = rmap.valueAt(i);
                    IntentReceiverLeaked leak = new IntentReceiverLeaked(
                            what + " " + who + " has leaked IntentReceiver "
                            + rd.getIntentReceiver() + " that was " +
                            "originally registered here. Are you missing a " +
                            "call to unregisterReceiver()?");
                    leak.setStackTrace(rd.getLocation().getStackTrace());
                    Slog.e(ActivityThread.TAG, leak.getMessage(), leak);
                    if (reportRegistrationLeaks) {
    
                        StrictMode.onIntentReceiverLeaked(leak);
                    }
                    try {
    
                        ActivityManager.getService().unregisterReceiver(
                                rd.getIIntentReceiver());
                    } catch (RemoteException e) {
    
                        throw e.rethrowFromSystemServer();
                    }
                }
            }
            mUnregisteredReceivers.remove(context);
        }

        synchronized (mServices) {
    
            //Slog.i(TAG, "Receiver registrations: " + mReceivers);
          //移除当前stop的service,并返回以当前service为key的map
            ArrayMap<ServiceConnection, LoadedApk.ServiceDispatcher> smap =
                    mServices.remove(context);
            if (smap != null) {
    
              //分析service的泄漏
                for (int i = 0; i < smap.size(); i++) {
    
                    LoadedApk.ServiceDispatcher sd = smap.valueAt(i);
                    ServiceConnectionLeaked leak = new ServiceConnectionLeaked(
                            what + " " + who + " has leaked ServiceConnection "
                            + sd.getServiceConnection() + " that was originally bound here");
                    leak.setStackTrace(sd.getLocation().getStackTrace());
                    Slog.e(ActivityThread.TAG, leak.getMessage(), leak);
                    if (reportRegistrationLeaks) {
    
                        StrictMode.onServiceConnectionLeaked(leak);
                    }
                    try {
    
                        ActivityManager.getService().unbindService(
                                sd.getIServiceConnection());
                    } catch (RemoteException e) {
    
                        throw e.rethrowFromSystemServer();
                    }
                    sd.doForget();
                }
            }
            mUnboundServices.remove(context);
            //Slog.i(TAG, "Service registrations: " + mServices);
        }