// Collect all system packages.
mSystemAppDir = new File(Environment.getRootDirectory(), "app");
mSystemInstallObserver = new AppDirObserver(mSystemAppDir.getPath(), OBSERVER_EVENTS, true);
mSystemInstallObserver.startWatching();
scanDirLI(mSystemAppDir, PackageParser.PARSE_IS_SYSTEM | PackageParser.PARSE_IS_SYSTEM_DIR, scanMode, 0);

private void scanDirLI(File dir, int flags, int scanMode, long currentTime {String[] files = dir.list();……int i;for (i=0; i<files.length; i++) {File file = new File(dir, files[i]);……PackageParser.Package pkg = scanPackageLI(file, flags|PackageParser.PARSE_MUST_BE_APK, scanMode, currentTime);……}
}

String[] files = dir.list();

else if (tagName.equals("receiver")) {Activity a = parseActivity(owner, res, parser, attrs, flags, outError, true, false);if (a == null) {mParseError = PackageManager.INSTALL_PARSE_FAILED_MANIFEST_MALFORMED;return false;}owner.receivers.add(a);
}

public final static class Activity extends Component<ActivityIntentInfo> {public final ActivityInfo info;public Activity(final ParseComponentArgs args, final ActivityInfo _info) {super(args, _info);info = _info;info.applicationInfo = args.owner.applicationInfo;}public void setPackageName(String packageName) {super.setPackageName(packageName);info.packageName = packageName;}……
}

// All available receivers, for your resolving pleasure.
final ActivityIntentResolver mReceivers = new ActivityIntentResolver();、

    public void addFilter(F f) {......mFilters.add(f);int numS = register_intent_filter(f, f.schemesIterator(),mSchemeToFilter, "      Scheme: ");int numT = register_mime_types(f, "      Type: ");//根据我下面红色文字的假设，这里numS和numT应该都为0if (numS == 0 && numT == 0) {register_intent_filter(f, f.actionsIterator(),mActionToFilter, "      Action: ");}if (numT != 0) {register_intent_filter(f, f.actionsIterator(),mTypedActionToFilter, "      TypedAction: ");}}

private final int register_intent_filter(F filter, Iterator<String> i,HashMap<String, ArrayList<F>> dest, String prefix) {if (i == null) {return 0;}int num = 0;while (i.hasNext()) {String name = i.next();num++;if (localLOGV) Slog.v(TAG, prefix + name);ArrayList<F> array = dest.get(name);if (array == null) {//Slog.v(TAG, "Creating new array for " + name);array = new ArrayList<F>();dest.put(name, array);}array.add(filter);}return num;
}

ReceiverList rl = (ReceiverList)mRegisteredReceivers.get(receiver.asBinder());
if (rl == null) {rl = new ReceiverList(this, callerApp,Binder.getCallingPid(),Binder.getCallingUid(), receiver);if (rl.app != null) {rl.app.receivers.add(rl);} else {try {receiver.asBinder().linkToDeath(rl, 0);} catch (RemoteException e) {return sticky;}rl.linkedToDeath = true;}mRegisteredReceivers.put(receiver.asBinder(), rl);
}
BroadcastFilter bf = new BroadcastFilter(filter, rl, callerPackage, permission);
rl.add(bf);
if (!bf.debugCheck()) {Slog.w(TAG, "==> For Dynamic broadast");
}
mReceiverResolver.addFilter(bf); 

mReceiverResolver.addFilter(bf);

/*** Resolver for broadcast intents to registered receivers.* Holds BroadcastFilter (subclass of IntentFilter).*/
final IntentResolver<BroadcastFilter, BroadcastFilter> mReceiverResolver = new IntentResolver<BroadcastFilter, BroadcastFilter>() {@Overrideprotected boolean allowFilterResult(BroadcastFilter filter, List<BroadcastFilter> dest) {IBinder target = filter.receiverList.receiver.asBinder();for (int i=dest.size()-1; i>=0; i--) {if (dest.get(i).receiverList.receiver.asBinder() == target) {return false;}}return true;}@Overrideprotected String packageForFilter(BroadcastFilter filter) {return filter.packageName;}
};

String[] files = dir.list();