源码 ContentProvider 的创建过程

ContentProvider #  当应用启动时，入口方法 为 ActivityThread 的main ， 1、 在main 方法中 创建 ActivityThread 的实例 并创建主线程的消息队列 2、 在 ActivityThread 的 attach 方法中会远程调用 AMS 的 attachApplicationLocked 方法   并将 ApplicationThread 对象提供给 AMS 3、 ApplicationThread 是一个 Binder 对象，他的 Binder 接口是 IApplication   主要用于 ActivityThread 和 AMS 的通信 4、在 AMS 的 attachApplicationLocked 方法中，会调用 Applicationthread 的 bindApplication，   这个过程同样跨进程完成的， 5、bindApplication 的逻辑经过 ActivityThread 中 mH 切换到  ActivityThread 中的     handerBindApplication  方法，handerBindApplication 会创建 Application  对象   并加载 ContentProvider ActivityThread  #  main  ， attach       public static void main(String[] args) { Looper.prepareMainLooper(); ActivityThread thread = new ActivityThread(); thread.attach(false); if (sMainThreadHandler == null) { sMainThreadHandler = thread.getHandler(); } AsyncTask.init(); if (false) { Looper.myLooper().setMessageLogging(new LogPrinter(Log.DEBUG, "ActivityThread")); } Looper.loop(); throw new RuntimeException("Main thread loop unexpectedly exited"); } private void attach(boolean system) { sCurrentActivityThread = this; mSystemThread = system; if (!system) { ViewRootImpl.addFirstDrawHandler(new Runnable() { @Override public void run() { ensureJitEnabled(); } }); android.ddm.DdmHandleAppName.setAppName("<pre-initialized>", UserHandle.myUserId()); RuntimeInit.setApplicationObject(mAppThread.asBinder()); final IActivityManager mgr = ActivityManagerNative.getDefault(); try { mgr.attachApplication(mAppThread); } catch (RemoteException ex) { // Ignore }AMS  #  attachApplicationLocked   private final boolean attachApplicationLocked(IApplicationThread thread, int pid) { try { 。。。 thread.bindApplication(processName, appInfo, providers, app.instrumentationClass, profilerInfo, app.instrumentationArguments, app.instrumentationWatcher, app.instrumentationUiAutomationConnection, testMode, enableOpenGlTrace, isRestrictedBackupMode || !normalMode, app.persistent, new Configuration(mConfiguration), app.compat, getCommonServicesLocked(), mCoreSettingsObserver.getCoreSettingsLocked()); updateLruProcessLocked(app, false, null); app.lastRequestedGc = app.lastLowMemory = SystemClock.uptimeMillis(); } catch (Exception e) { // todo: Yikes! What should we do? For now we will try to // start another process, but that could easily get us in // an infinite loop of restarting processes... Slog.wtf(TAG, "Exception thrown during bind of " + app, e); app.resetPackageList(mProcessStats); app.unlinkDeathRecipient(); startProcessLocked(app, "bind fail", processName); return false; } ｝

ActivityThread  #  bindApplication

public final void bindApplication(String processName, ApplicationInfo appInfo, List<ProviderInfo> providers, ComponentName instrumentationName, ProfilerInfo profilerInfo, Bundle instrumentationArgs, IInstrumentationWatcher instrumentationWatcher, IUiAutomationConnection instrumentationUiConnection, int debugMode, boolean enableOpenGlTrace, boolean isRestrictedBackupMode, boolean persistent, Configuration config, CompatibilityInfo compatInfo, Map<String, IBinder> services, Bundle coreSettings) { IPackageManager pm = getPackageManager(); android.content.pm.PackageInfo pi = null; try { pi = pm.getPackageInfo(appInfo.packageName, 0, UserHandle.myUserId()); } catch (RemoteException e) { } if (pi != null) { boolean sharedUserIdSet = (pi.sharedUserId != null); boolean processNameNotDefault = (pi.applicationInfo != null && !appInfo.packageName.equals(pi.applicationInfo.processName)); boolean sharable = (sharedUserIdSet || processNameNotDefault); // Tell the VMRuntime about the application, unless it is shared // inside a process. if (!sharable) { VMRuntime.registerAppInfo(appInfo.packageName, appInfo.dataDir, appInfo.processName); } } sendMessage(H.BIND_APPLICATION, data); }ActivityThread  #  handleBindApplication private void handleBindApplication(AppBindData data) { /** * Initialize the default http proxy in this process for the reasons we set the time zone. */ IBinder b = ServiceManager.getService(Context.CONNECTIVITY_SERVICE); if (data.instrumentationName != null) { InstrumentationInfo ii = null; ii = appContext.getPackageManager(). getInstrumentationInfo(data.instrumentationName, 0); ..... LoadedApk pi = getPackageInfo(instrApp, data.compatInfo, appContext.getClassLoader(), false, true, false); ContextImpl instrContext = ContextImpl.createAppContext(this, pi); try { java.lang.ClassLoader cl = instrContext.getClassLoader(); mInstrumentation = (Instrumentation) cl.loadClass(data.instrumentationName.getClassName()).newInstance(); } catch (Exception e) { } mInstrumentation.init(this, instrContext, appContext, new ComponentName(ii.packageName, ii.name), data.instrumentationWatcher, data.instrumentationUiAutomationConnection); try { Application app = data.info.makeApplication(data.restrictedBackupMode, null); mInitialApplication = app; // don't bring up providers in restricted mode; they may depend on the // app's custom Application class if (!data.restrictedBackupMode) { List<ProviderInfo> providers = data.providers; if (providers != null) { installContentProviders(app, providers); // For process that contains content providers, we want to // ensure that the JIT is enabled "at some point". mH.sendEmptyMessageDelayed(H.ENABLE_JIT, 10*1000); } } try { mInstrumentation.onCreate(data.instrumentationArgs); } catch (Exception e) { throw new RuntimeException( "Exception thrown in onCreate() of " + data.instrumentationName + ": " + e.toString(), e); } try { mInstrumentation.callApplicationOnCreate(app); } catch (Exception e) { if (!mInstrumentation.onException(app, e)) { throw new RuntimeException( "Unable to create application " + app.getClass().getName() + ": " + e.toString(), e); } } } finally { StrictMode.setThreadPolicy(savedPolicy); } } }ActivityThread  #  installContentProviders # installProviders private IActivityManager.ContentProviderHolder installProvider(Context context, IActivityManager.ContentProviderHolder holder, ProviderInfo info, boolean noisy, boolean noReleaseNeeded, boolean stable) { ContentProvider localProvider = null; IContentProvider provider; try { final java.lang.ClassLoader cl = c.getClassLoader(); localProvider = (ContentProvider)cl. loadClass(info.name).newInstance(); provider = localProvider.getIContentProvider(); if (provider == null) { Slog.e(TAG, "Failed to instantiate class " + info.name + " from sourceDir " + info.applicationInfo.sourceDir); return null; } if (DEBUG_PROVIDER) Slog.v( TAG, "Instantiating local provider " + info.name); // XXX Need to create the correct context for this provider. localProvider.attachInfo(c, info);ContentProvider # attachInfo private void attachInfo(Context context, ProviderInfo info, boolean testing) { mNoPerms = testing; /* * Only allow it to be set once, so after the content service gives * this to us clients can't change it. */ if (mContext == null) { mContext = context; if (context != null) { mTransport.mAppOpsManager = (AppOpsManager) context.getSystemService( Context.APP_OPS_SERVICE); } mMyUid = Process.myUid(); if (info != null) { setReadPermission(info.readPermission); setWritePermission(info.writePermission); setPathPermissions(info.pathPermissions); mExported = info.exported; mSingleUser = (info.flags & ProviderInfo.FLAG_SINGLE_USER) != 0; setAuthorities(info.authority); } ContentProvider.this.onCreate(); } } Android API ： http://www.android-doc.com/reference/packages.html   http://tool.oschina.net/uploads/apidocs/android/reference/packages.html   Android 源码： http://androidxref.com/