文章目录

• 一、 ContentProvider 创建过程分析
• 二、 ActivityThread 中的 H 处理 BIND_APPLICATION 消息
• 三、 ActivityThread 中的 handleBindApplication 方法
• 四、 ActivityThread 中的 installContentProviders 方法 ( 创建 ContentProvider 内容提供者 )
• 五、 ActivityThread 中的 installProvider 方法 ( 创建 ContentProvider 内容提供者 )
• 六、 ContentProvider 中的 attachInfo 方法
• 六、 LoadedApk 中的 mApplication 成员
• 七、 ActivityThread 涉及源码
• 八、 Instrumentation 涉及源码
• 九、 LoadedApk 涉及源码

一、 ContentProvider 创建过程分析

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创建 自定义 ContentProvider , 并在其 onCreate 方法中打印上下文信息 :

package kim.hsl.dex;import android.content.ContentProvider; import android.content.ContentValues; import android.database.Cursor; import android.net.Uri; import android.util.Log;import androidx.annotation.NonNull; import androidx.annotation.Nullable;public class MyProvider extends ContentProvider {@Overridepublic boolean onCreate() {/*验证 Application 是否替换成功打印 Application , ApplicationContext , ApplicationInfo*/Log.i("octopus.MyProvider", "Application : " + getContext());Log.i("octopus.MyProvider", "ApplicationContext : " + getContext().getApplicationContext());Log.i("octopus.MyProvider", "ApplicationInfo.className : " + getContext().getApplicationInfo().className);return true;}@Nullable@Overridepublic Cursor query(@NonNull Uri uri, @Nullable String[] projection, @Nullable String selection, @Nullable String[] selectionArgs, @Nullable String sortOrder) {return null;}@Nullable@Overridepublic String getType(@NonNull Uri uri) {return null;}@Nullable@Overridepublic Uri insert(@NonNull Uri uri, @Nullable ContentValues values) {return null;}@Overridepublic int delete(@NonNull Uri uri, @Nullable String selection, @Nullable String[] selectionArgs) {Log.e("octopus.MyProvider", "MyProvider delete : " + getContext());return 0;}@Overridepublic int update(@NonNull Uri uri, @Nullable ContentValues values, @Nullable String selection, @Nullable String[] selectionArgs) {return 0;} }

清单文件配置 :

<providerandroid:exported="true"android:name=".MyProvider"android:authorities="kim.hsl.dex.myprovider" />

在 Activity 中使用 ContentProvider :

contentResolver.delete(Uri.parse("content://kim.hsl.dex.myprovider"),null,null)

根据打印出来的日志文件分析 , ContentProvider 的 onCreate 方法调用 , 在代理 Application 类 ProxyApplication 的 onCreat 方法之后 , 在 真实 Application 类 MyApplication 的 onCreate 方法之前 ;

下图的日志中 , 分别在 ProxyApplication ( 蓝色部分 ) , MyApplication ( 红色部分 ) , ContentProvider ( 红色部分 ) 中打印的日志 ;

在 ContentProvider 中使用的 Application 仍然是代理 Application , 并不是真实应用的 Application ;

二、 ActivityThread 中的 H 处理 BIND_APPLICATION 消息

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Activity , Service , BroadcastReceiver 组件 , 创建时 , 都是在 Application 的 onCreate 方法完成之后进行创建 ;

ContentProvider 组件的创建比较特殊 , 当系统发现该应用在 AndroidManifest.xml 中注册了 ContentProvider 组件时 , 会安装该 ContentProvider ;

在 ActivityThread 中 , H ( Handler 子类 ) 接收到 BIND_APPLICATION 消息时 , 进行初始化 ContentProvider 组件的操作 , 调用 handleBindApplication() 方法 , 进行相关操作 ;

public final class ActivityThread {private class H extends Handler {public static final int BIND_APPLICATION = 110;public void handleMessage(Message msg) {switch (msg.what) {case BIND_APPLICATION:Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "bindApplication");AppBindData data = (AppBindData)msg.obj;handleBindApplication(data);Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);break;} // switch} // handleMessage} // private class H extends Handler}

参考路径 : frameworks/base/core/java/android/app/ActivityThread.java

三、 ActivityThread 中的 handleBindApplication 方法

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在 handleBindApplication 方法中 , 先创建了 Application , 此时调用了 Application 的 attachBaseContext 方法 ,

// If the app is being launched for full backup or restore, bring it up in // a restricted environment with the base application class. // ★ 创建 Application // ★ 此时调用 Application 的 attachBaseContext 方法 Application app = data.info.makeApplication(data.restrictedBackupMode, null); mInitialApplication = app;

在这之后马上创建 ContentProvider , 此时还没有调用 Application 的 onCreate 方法 ,

// don't bring up providers in restricted mode; they may depend on the // app's custom Application class // ★ 在此处创建 ContentProvider if (!data.restrictedBackupMode) {if (!ArrayUtils.isEmpty(data.providers)) {// ★ 安装 ContentProviderinstallContentProviders(app, data.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);} }

在创建了 ContentProvider 之后 , 才调用的 Application 的 onCreate 方法 ;

// ★ 此处调用 Application 的 onCreate 方法 mInstrumentation.onCreate(data.instrumentationArgs);

ContentProvider 组件在代理 Application 类 ProxyApplication 的 attachBaseContext 方法之后 , onCreate 方法之前就创建了 , 而 代理 Application 类 ProxyApplication 替换为真实的 Application 类 MyApplication 是在 ProxyApplication 的 onCreate 方法中进行的 , 也就是说 ContentProvider 在 Application 替换之前就创建完成了 ;

因此打印的日志中 , ContentProvider 的 onCreate 方法在 ProxyApplication 的 attachBaseContext 方法之后调用 , 在 ProxyApplication 的 onCreate 方法之前调用 ;

主要源码 :

public final class ActivityThread {private class H extends Handler {public static final int LAUNCH_ACTIVITY = 100;public static final int BIND_APPLICATION = 110;public static final int CREATE_SERVICE = 114;public static final int RECEIVER = 113;public void handleMessage(Message msg) {if (DEBUG_MESSAGES) Slog.v(TAG, ">>> handling: " + codeToString(msg.what));switch (msg.what) {case LAUNCH_ACTIVITY: {Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "activityStart");final ActivityClientRecord r = (ActivityClientRecord) msg.obj;r.packageInfo = getPackageInfoNoCheck(r.activityInfo.applicationInfo, r.compatInfo);// ★ 调用 handleLaunchActivity 方法处理该消息handleLaunchActivity(r, null, "LAUNCH_ACTIVITY");Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);} break;case BIND_APPLICATION:Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "bindApplication");AppBindData data = (AppBindData)msg.obj;handleBindApplication(data);Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);break;case CREATE_SERVICE:Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, ("serviceCreate: " + String.valueOf(msg.obj)));handleCreateService((CreateServiceData)msg.obj);Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);break;case RECEIVER:Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "broadcastReceiveComp");handleReceiver((ReceiverData)msg.obj);maybeSnapshot();Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);break;} // switch} // handleMessage} // private class H extends Handlerprivate void handleLaunchActivity(ActivityClientRecord r, Intent customIntent, String reason) {// ★ 此处创建了一个 Activity Activity a = performLaunchActivity(r, customIntent);}private Activity performLaunchActivity(ActivityClientRecord r, Intent customIntent) {// System.out.println("##### [" + System.currentTimeMillis() + "] ActivityThread.performLaunchActivity(" + r + ")");ActivityInfo aInfo = r.activityInfo;ContextImpl appContext = createBaseContextForActivity(r);// ★ 声明 Activity Activity activity = null;try {java.lang.ClassLoader cl = appContext.getClassLoader();// ★ 创建 Activity , 与创建 Application 类似 activity = mInstrumentation.newActivity(cl, component.getClassName(), r.intent);} catch (Exception e) {}try {// ★ 这里是传入 Activity attach 方法中的 Application , 赋值给 Activity 中的 mApplication 成员 Application app = r.packageInfo.makeApplication(false, mInstrumentation);if (activity != null) {appContext.setOuterContext(activity);// ★ 此处调用了 Activity 的 attach 方法 , 给 Activity 中的 mApplication 成员赋值activity.attach(appContext, this, getInstrumentation(), r.token,r.ident, app, r.intent, r.activityInfo, title, r.parent,r.embeddedID, r.lastNonConfigurationInstances, config,r.referrer, r.voiceInteractor, window, r.configCallback);return activity;}// ★ 创建 Service 组件private void handleCreateService(CreateServiceData data) {LoadedApk packageInfo = getPackageInfoNoCheck(data.info.applicationInfo, data.compatInfo);Service service = null;try {java.lang.ClassLoader cl = packageInfo.getClassLoader();// ★ 创建 Service service = (Service) cl.loadClass(data.info.name).newInstance();} catch (Exception e) {}try {ContextImpl context = ContextImpl.createAppContext(this, packageInfo);context.setOuterContext(service);Application app = packageInfo.makeApplication(false, mInstrumentation);// ★ 调用了 Service 的 attach 方法 service.attach(context, this, data.info.name, data.token, app,ActivityManager.getService());service.onCreate();} catch (Exception e) {}}private void handleReceiver(ReceiverData data) {Application app;// ★ 声明 BroadcastReceiverBroadcastReceiver receiver;ContextImpl context;try {app = packageInfo.makeApplication(false, mInstrumentation);context = (ContextImpl) app.getBaseContext();// ★ 创建 BroadcastReceiver 对象receiver = (BroadcastReceiver)cl.loadClass(component).newInstance();} catch (Exception e) {}try {// ★ 调用 BroadcastReceiver 广播接收者的 onReceive 方法// 这里注意传入的参数就是 context.getReceiverRestrictedContext()receiver.onReceive(context.getReceiverRestrictedContext(),data.intent);} catch (Exception e) {} finally {}}private void handleBindApplication(AppBindData data) {// Allow disk access during application and provider setup. This could// block processing ordered broadcasts, but later processing would// probably end up doing the same disk access.final StrictMode.ThreadPolicy savedPolicy = StrictMode.allowThreadDiskWrites();try {// If the app is being launched for full backup or restore, bring it up in// a restricted environment with the base application class.// ★ 创建 Application // ★ 此时调用 Application 的 attachBaseContext 方法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// ★ 在此处创建 ContentProvider if (!data.restrictedBackupMode) {if (!ArrayUtils.isEmpty(data.providers)) {// ★ 安装 ContentProviderinstallContentProviders(app, data.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);}}// Do this after providers, since instrumentation tests generally start their// test thread at this point, and we don't want that racing.try {// ★ 此处调用 Application 的 onCreate 方法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);}}}

参考路径 : frameworks/base/core/java/android/app/ActivityThread.java

四、 ActivityThread 中的 installContentProviders 方法 ( 创建 ContentProvider 内容提供者 )

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ActivityThread 中的 installContentProviders 方法 , 传入两个参数 :

Context context 参数 : 之前创建的 Application 上下文对象 , 这个 Application 对象是替换前的 代理 Application 对象 , 是在 AndroidManifest.xml 中的 application 节点信息 ;

List<ProviderInfo> providers 参数 : ProviderInfo 集合 , 是为生成多个 ContentProvider 准备的 , ProviderInfo 与 ApplicationInfo 是相同的 , ApplicationInfo 是 AndroidManifest.xml 中的 application 节点信息 , ProviderInfo 是 AndroidManifest.xml 中的 provider 节点信息 ;

在该 installContentProviders 方法中 , 调用了 installProvider 为每个 ProviderInfo 各自创建一个 ContentProvider ;

相关代码示例 :

public final class ActivityThread {// ★ 传入两个参数 , // ★ Context context : 之前创建的 Application 上下文对象 , // 这个 Application 对象是替换前的 代理 Application 对象 , // 是在 AndroidManifest.xml 中的 application 节点信息 , // ★ List<ProviderInfo> providers , 这里的 ProviderInfo 集合 // ★ 是为生成多个 ContentProvider 准备的 // ★ ProviderInfo 与 ApplicationInfo 是相同的// ★ ApplicationInfo 是 AndroidManifest.xml 中的 application 节点信息 // ★ ProviderInfo 是 AndroidManifest.xml 中的 provider 节点信息 private void installContentProviders(Context context, List<ProviderInfo> providers) {// ★ 存放创建的多个 ContentProvider final ArrayList<ContentProviderHolder> results = new ArrayList<>();// ★ 创建多个 ContentProvider for (ProviderInfo cpi : providers) {// ★ 注意这里 installProvider 的第一个参数是 ProxyApplication 类型的ContentProviderHolder cph = installProvider(context, null, cpi,false /*noisy*/, true /*noReleaseNeeded*/, true /*stable*/);if (cph != null) {cph.noReleaseNeeded = true;results.add(cph);}}}}

参考路径 : frameworks/base/core/java/android/app/ActivityThread.java

五、 ActivityThread 中的 installProvider 方法 ( 创建 ContentProvider 内容提供者 )

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在 installProvider 方法中 , 通过 反射创建 ContentProvider ;

// ★ 反射创建 ContentProvider localProvider = (ContentProvider)cl.loadClass(info.name).newInstance();

在 创建 ContentProvider 之后 , 调用了 attachInfo 函数 , 注意此处与 Activity , Service , BrocastReceiver 不同 , 这三个组件创建后调用的是 attach 函数 ;

// XXX Need to create the correct context for this provider. // ★ 创建 ContentProvider 之后 , 调用了 attachInfo 函数 // 注意此处与 Activity , Service , BrocastReceiver 不同 , // 这三个组件创建后调用的是 attach 函数 localProvider.attachInfo(c, info);

这里分析 attachInfo 中的 c 参数 , 也就是 Context 上下文的获取过程 :

声明空的 Context c 对象 ,

// ★ 该上下文对象很重要 Context c = null;

获取 ApplicationInfo 信息 ApplicationInfo ai , 即 AndroidManifest.xml 中配置的 application 节点信息

// 该 ApplicationInfo 是 AndroidManifest.xml 中配置的 application 节点信息 ApplicationInfo ai = info.applicationInfo;

进行如下三个分支的判定 :

• 分支一 : if (context.getPackageName().equals(ai.packageName)) : 在应用中配置的代理 Application 包名与真实 Application 包名都是相等的 ;
• 分之二 : else if (mInitialApplication != null && mInitialApplication.getPackageName().equals(ai.packageName)) : 与分支一类似 , 也是要求包名相等 ;
• 分支三 : 上面两个分支没有命中 , 就执行第三个分支 ;

// ★ 该上下文对象很重要 Context c = null;// 该 ApplicationInfo 是 AndroidManifest.xml 中配置的 application 节点信息ApplicationInfo ai = info.applicationInfo;// 该 context 是 ProxyApplication , 代理 Application if (context.getPackageName().equals(ai.packageName)) {// 在应用中配置的代理 Application 包名与真实 Application 包名都是相等的// 该分支是命中的 c = context;} else if (mInitialApplication != null &&mInitialApplication.getPackageName().equals(ai.packageName)) {// 该分支中 mInitialApplication 就是 Context context 参数 , 肯定不为空 // 该分支无法命中 c = mInitialApplication;} else {// 上述两个分支都无法命中 , 才进入该分支 // 需要将代理 Application 的包名 与 真实应用的包名设置成不同的// 此时上面两个分支都无法命中 try {c = context.createPackageContext(ai.packageName,Context.CONTEXT_INCLUDE_CODE);} catch (PackageManager.NameNotFoundException e) {// Ignore}}

上面的分支一 与 分支二 都是将 代理 Application 分支 , 因此必须要命中第三个分支 ;

如果将 代理 Application 的 getPackageName() 获取包名的方法返回空 , 此时肯定无法命中前两个分支 , 只能命中第三分支 ;

相关代码示例 :

public final class ActivityThread {/*** Installs the provider.** Providers that are local to the process or that come from the system server* may be installed permanently which is indicated by setting noReleaseNeeded to true.* Other remote providers are reference counted. The initial reference count* for all reference counted providers is one. Providers that are not reference* counted do not have a reference count (at all).** This method detects when a provider has already been installed. When this happens,* it increments the reference count of the existing provider (if appropriate)* and returns the existing provider. This can happen due to concurrent* attempts to acquire the same provider.*/private ContentProviderHolder installProvider(Context context,ContentProviderHolder holder, ProviderInfo info,boolean noisy, boolean noReleaseNeeded, boolean stable) {// ★ 声明 ContentProvider ContentProvider localProvider = null;IContentProvider provider;if (holder == null || holder.provider == null) {if (DEBUG_PROVIDER || noisy) {Slog.d(TAG, "Loading provider " + info.authority + ": "+ info.name);}// 该上下文对象很重要 Context c = null;ApplicationInfo ai = info.applicationInfo;// 该 context 是 ProxyApplication , 代理 Application if (context.getPackageName().equals(ai.packageName)) {// 在应用中配置的代理 Application 包名与真实 Application 包名都是相等的// 该分支是命中的 c = context;} else if (mInitialApplication != null &&mInitialApplication.getPackageName().equals(ai.packageName)) {// 该分支中 mInitialApplication 就是 Context context 参数 , 肯定不为空 // 该分支无法命中 c = mInitialApplication;} else {// 上述两个分支都无法命中 , 才进入该分支 // 需要将代理 Application 的包名 与 真实应用的包名设置成不同的// 此时上面两个分支都无法命中 try {c = context.createPackageContext(ai.packageName,Context.CONTEXT_INCLUDE_CODE);} catch (PackageManager.NameNotFoundException e) {// Ignore}}if (c == null) {Slog.w(TAG, "Unable to get context for package " +ai.packageName +" while loading content provider " +info.name);return null;}try {final java.lang.ClassLoader cl = c.getClassLoader();// ★ 反射创建 ContentProvider 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.// ★ 创建 ContentProvider 之后 , 调用了 attachInfo 函数 // 注意此处与 Activity , Service , BrocastReceiver 不同 , // 这三个组件创建后调用的是 attach 函数localProvider.attachInfo(c, info);} catch (java.lang.Exception e) {return null;}} else {}return retHolder;}}

参考路径 : frameworks/base/core/java/android/app/ActivityThread.java

六、 ContentProvider 中的 attachInfo 方法

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在 ContentProvider 中的 attachInfo(Context context, ProviderInfo info) 方法中 , 调用了重载的三个参数的 attachInfo(Context context, ProviderInfo info, boolean testing) 方法 , 其中就有关于上下文对象的赋值 mContext = context , 注意此处进行了上下文赋值 , 就是代理 Application , ProxyApplication , 在 ContentProvider 组件中调用 getContext 获取上下文对象 , 获取的就是该对象 ;

// ★ 注意此处进行了上下文赋值 , 就是代理 Application , ProxyApplication // ★ 在 ContentProvider 组件中调用 getContext 获取上下文对象 // ★ 获取的就是该对象 mContext = context;

ContentProvider 相关源码 :

public abstract class ContentProvider implements ComponentCallbacks2 {/*** ★ ContentProvider 安装后, 回调该函数通知其本身.** @param context ContentProvider 运行的上下文对象 * @param info ContentProvider 组件的注册信息 */public void attachInfo(Context context, ProviderInfo info) {attachInfo(context, info, false);}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) {// ★ 注意此处进行了上下文赋值 , 就是代理 Application , ProxyApplication // ★ 在 ContentProvider 组件中调用 getContext 获取上下文对象 // ★ 获取的就是该对象 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();}}}

参考源码路径 : frameworks/base/core/java/android/content/ContentProvider.java

六、 LoadedApk 中的 mApplication 成员

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LoadedApk 中的 mApplication 成员已经替换成了自定义的 Application , 不再是代理的 Application , 因此从 Service 组件中获取的 Application 是已经替换后的用户自定义的 Application , 不是代理 Application ;

Application 已经执行完毕 , Application 替换操作是在 Application 的 onCreate 方法中执行的 , 此处的 Activity 执行肯定在 Application 创建完毕之后执行的 ;

主要源码 :

public final class LoadedApk {public Application makeApplication(boolean forceDefaultAppClass,Instrumentation instrumentation) {// ★ 如果之前创建过 Application , 就直接使用 if (mApplication != null) {return mApplication;}} }

参考路径 : frameworks/base/core/java/android/app/LoadedApk.java

七、 ActivityThread 涉及源码

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public final class ActivityThread {private class H extends Handler {public static final int LAUNCH_ACTIVITY = 100;public static final int BIND_APPLICATION = 110;public static final int CREATE_SERVICE = 114;public static final int RECEIVER = 113;public void handleMessage(Message msg) {if (DEBUG_MESSAGES) Slog.v(TAG, ">>> handling: " + codeToString(msg.what));switch (msg.what) {case LAUNCH_ACTIVITY: {Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "activityStart");final ActivityClientRecord r = (ActivityClientRecord) msg.obj;r.packageInfo = getPackageInfoNoCheck(r.activityInfo.applicationInfo, r.compatInfo);// ★ 调用 handleLaunchActivity 方法处理该消息handleLaunchActivity(r, null, "LAUNCH_ACTIVITY");Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);} break;case BIND_APPLICATION:Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "bindApplication");AppBindData data = (AppBindData)msg.obj;handleBindApplication(data);Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);break;case CREATE_SERVICE:Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, ("serviceCreate: " + String.valueOf(msg.obj)));handleCreateService((CreateServiceData)msg.obj);Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);break;case RECEIVER:Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "broadcastReceiveComp");handleReceiver((ReceiverData)msg.obj);maybeSnapshot();Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);break;} // switch} // handleMessage} // private class H extends Handlerprivate void handleLaunchActivity(ActivityClientRecord r, Intent customIntent, String reason) {// If we are getting ready to gc after going to the background, well// we are back active so skip it.unscheduleGcIdler();mSomeActivitiesChanged = true;if (r.profilerInfo != null) {mProfiler.setProfiler(r.profilerInfo);mProfiler.startProfiling();}// Make sure we are running with the most recent config.handleConfigurationChanged(null, null);if (localLOGV) Slog.v(TAG, "Handling launch of " + r);// Initialize before creating the activityWindowManagerGlobal.initialize();// ★ 此处创建了一个 Activity Activity a = performLaunchActivity(r, customIntent);if (a != null) {r.createdConfig = new Configuration(mConfiguration);reportSizeConfigurations(r);Bundle oldState = r.state;handleResumeActivity(r.token, false, r.isForward,!r.activity.mFinished && !r.startsNotResumed, r.lastProcessedSeq, reason);if (!r.activity.mFinished && r.startsNotResumed) {// The activity manager actually wants this one to start out paused, because it// needs to be visible but isn't in the foreground. We accomplish this by going// through the normal startup (because activities expect to go through onResume()// the first time they run, before their window is displayed), and then pausing it.// However, in this case we do -not- need to do the full pause cycle (of freezing// and such) because the activity manager assumes it can just retain the current// state it has.performPauseActivityIfNeeded(r, reason);// We need to keep around the original state, in case we need to be created again.// But we only do this for pre-Honeycomb apps, which always save their state when// pausing, so we can not have them save their state when restarting from a paused// state. For HC and later, we want to (and can) let the state be saved as the// normal part of stopping the activity.if (r.isPreHoneycomb()) {r.state = oldState;}}} else {// If there was an error, for any reason, tell the activity manager to stop us.try {ActivityManager.getService().finishActivity(r.token, Activity.RESULT_CANCELED, null,Activity.DONT_FINISH_TASK_WITH_ACTIVITY);} catch (RemoteException ex) {throw ex.rethrowFromSystemServer();}}}private Activity performLaunchActivity(ActivityClientRecord r, Intent customIntent) {// System.out.println("##### [" + System.currentTimeMillis() + "] ActivityThread.performLaunchActivity(" + r + ")");ActivityInfo aInfo = r.activityInfo;if (r.packageInfo == null) {r.packageInfo = getPackageInfo(aInfo.applicationInfo, r.compatInfo,Context.CONTEXT_INCLUDE_CODE);}ComponentName component = r.intent.getComponent();if (component == null) {component = r.intent.resolveActivity(mInitialApplication.getPackageManager());r.intent.setComponent(component);}if (r.activityInfo.targetActivity != null) {component = new ComponentName(r.activityInfo.packageName,r.activityInfo.targetActivity);}ContextImpl appContext = createBaseContextForActivity(r);// ★ 声明 Activity Activity activity = null;try {java.lang.ClassLoader cl = appContext.getClassLoader();// ★ 创建 Activity , 与创建 Application 类似 activity = mInstrumentation.newActivity(cl, component.getClassName(), r.intent);StrictMode.incrementExpectedActivityCount(activity.getClass());r.intent.setExtrasClassLoader(cl);r.intent.prepareToEnterProcess();if (r.state != null) {r.state.setClassLoader(cl);}} catch (Exception e) {if (!mInstrumentation.onException(activity, e)) {throw new RuntimeException("Unable to instantiate activity " + component+ ": " + e.toString(), e);}}try {// ★ 这里是传入 Activity attach 方法中的 Application , 赋值给 Activity 中的 mApplication 成员 Application app = r.packageInfo.makeApplication(false, mInstrumentation);if (localLOGV) Slog.v(TAG, "Performing launch of " + r);if (localLOGV) Slog.v(TAG, r + ": app=" + app+ ", appName=" + app.getPackageName()+ ", pkg=" + r.packageInfo.getPackageName()+ ", comp=" + r.intent.getComponent().toShortString()+ ", dir=" + r.packageInfo.getAppDir());if (activity != null) {CharSequence title = r.activityInfo.loadLabel(appContext.getPackageManager());Configuration config = new Configuration(mCompatConfiguration);if (r.overrideConfig != null) {config.updateFrom(r.overrideConfig);}if (DEBUG_CONFIGURATION) Slog.v(TAG, "Launching activity "+ r.activityInfo.name + " with config " + config);Window window = null;if (r.mPendingRemoveWindow != null && r.mPreserveWindow) {window = r.mPendingRemoveWindow;r.mPendingRemoveWindow = null;r.mPendingRemoveWindowManager = null;}appContext.setOuterContext(activity);// ★ 此处调用了 Activity 的 attach 方法 , 给 Activity 中的 mApplication 成员赋值activity.attach(appContext, this, getInstrumentation(), r.token,r.ident, app, r.intent, r.activityInfo, title, r.parent,r.embeddedID, r.lastNonConfigurationInstances, config,r.referrer, r.voiceInteractor, window, r.configCallback);if (customIntent != null) {activity.mIntent = customIntent;}r.lastNonConfigurationInstances = null;checkAndBlockForNetworkAccess();activity.mStartedActivity = false;int theme = r.activityInfo.getThemeResource();if (theme != 0) {activity.setTheme(theme);}activity.mCalled = false;if (r.isPersistable()) {mInstrumentation.callActivityOnCreate(activity, r.state, r.persistentState);} else {mInstrumentation.callActivityOnCreate(activity, r.state);}if (!activity.mCalled) {throw new SuperNotCalledException("Activity " + r.intent.getComponent().toShortString() +" did not call through to super.onCreate()");}r.activity = activity;r.stopped = true;if (!r.activity.mFinished) {activity.performStart();r.stopped = false;}if (!r.activity.mFinished) {if (r.isPersistable()) {if (r.state != null || r.persistentState != null) {mInstrumentation.callActivityOnRestoreInstanceState(activity, r.state,r.persistentState);}} else if (r.state != null) {mInstrumentation.callActivityOnRestoreInstanceState(activity, r.state);}}if (!r.activity.mFinished) {activity.mCalled = false;if (r.isPersistable()) {mInstrumentation.callActivityOnPostCreate(activity, r.state,r.persistentState);} else {mInstrumentation.callActivityOnPostCreate(activity, r.state);}if (!activity.mCalled) {throw new SuperNotCalledException("Activity " + r.intent.getComponent().toShortString() +" did not call through to super.onPostCreate()");}}}r.paused = true;mActivities.put(r.token, r);} catch (SuperNotCalledException e) {throw e;} catch (Exception e) {if (!mInstrumentation.onException(activity, e)) {throw new RuntimeException("Unable to start activity " + component+ ": " + e.toString(), e);}}return activity;}// ★ 创建 Service 组件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();LoadedApk packageInfo = getPackageInfoNoCheck(data.info.applicationInfo, data.compatInfo);Service service = null;try {java.lang.ClassLoader cl = packageInfo.getClassLoader();// ★ 创建 Service service = (Service) cl.loadClass(data.info.name).newInstance();} catch (Exception e) {if (!mInstrumentation.onException(service, e)) {throw new RuntimeException("Unable to instantiate service " + data.info.name+ ": " + e.toString(), e);}}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);// ★ 调用了 Service 的 attach 方法 service.attach(context, this, data.info.name, data.token, app,ActivityManager.getService());service.onCreate();mServices.put(data.token, service);try {ActivityManager.getService().serviceDoneExecuting(data.token, SERVICE_DONE_EXECUTING_ANON, 0, 0);} catch (RemoteException e) {throw e.rethrowFromSystemServer();}} catch (Exception e) {if (!mInstrumentation.onException(service, e)) {throw new RuntimeException("Unable to create service " + data.info.name+ ": " + e.toString(), e);}}}private void handleReceiver(ReceiverData data) {// If we are getting ready to gc after going to the background, well// we are back active so skip it.unscheduleGcIdler();String component = data.intent.getComponent().getClassName();LoadedApk packageInfo = getPackageInfoNoCheck(data.info.applicationInfo, data.compatInfo);IActivityManager mgr = ActivityManager.getService();Application app;// ★ 声明 BroadcastReceiverBroadcastReceiver receiver;ContextImpl context;try {app = packageInfo.makeApplication(false, mInstrumentation);context = (ContextImpl) app.getBaseContext();if (data.info.splitName != null) {context = (ContextImpl) context.createContextForSplit(data.info.splitName);}java.lang.ClassLoader cl = context.getClassLoader();data.intent.setExtrasClassLoader(cl);data.intent.prepareToEnterProcess();data.setExtrasClassLoader(cl);// ★ 创建 BroadcastReceiver 对象receiver = (BroadcastReceiver)cl.loadClass(component).newInstance();} catch (Exception e) {if (DEBUG_BROADCAST) Slog.i(TAG,"Finishing failed broadcast to " + data.intent.getComponent());data.sendFinished(mgr);throw new RuntimeException("Unable to instantiate receiver " + component+ ": " + e.toString(), e);}try {if (localLOGV) Slog.v(TAG, "Performing receive of " + data.intent+ ": app=" + app+ ", appName=" + app.getPackageName()+ ", pkg=" + packageInfo.getPackageName()+ ", comp=" + data.intent.getComponent().toShortString()+ ", dir=" + packageInfo.getAppDir());sCurrentBroadcastIntent.set(data.intent);receiver.setPendingResult(data);// ★ 调用 BroadcastReceiver 广播接收者的 onReceive 方法// 这里注意传入的参数就是 context.getReceiverRestrictedContext()receiver.onReceive(context.getReceiverRestrictedContext(),data.intent);} catch (Exception e) {if (DEBUG_BROADCAST) Slog.i(TAG,"Finishing failed broadcast to " + data.intent.getComponent());data.sendFinished(mgr);if (!mInstrumentation.onException(receiver, e)) {throw new RuntimeException("Unable to start receiver " + component+ ": " + e.toString(), e);}} finally {sCurrentBroadcastIntent.set(null);}if (receiver.getPendingResult() != null) {data.finish();}}private void handleBindApplication(AppBindData data) {// Register the UI Thread as a sensitive thread to the runtime.VMRuntime.registerSensitiveThread();if (data.trackAllocation) {DdmVmInternal.enableRecentAllocations(true);}// Note when this process has started.Process.setStartTimes(SystemClock.elapsedRealtime(), SystemClock.uptimeMillis());mBoundApplication = data;mConfiguration = new Configuration(data.config);mCompatConfiguration = new Configuration(data.config);mProfiler = new Profiler();if (data.initProfilerInfo != null) {mProfiler.profileFile = data.initProfilerInfo.profileFile;mProfiler.profileFd = data.initProfilerInfo.profileFd;mProfiler.samplingInterval = data.initProfilerInfo.samplingInterval;mProfiler.autoStopProfiler = data.initProfilerInfo.autoStopProfiler;mProfiler.streamingOutput = data.initProfilerInfo.streamingOutput;}// send up app name; do this *before* waiting for debuggerProcess.setArgV0(data.processName);android.ddm.DdmHandleAppName.setAppName(data.processName,UserHandle.myUserId());if (data.persistent) {// Persistent processes on low-memory devices do not get to// use hardware accelerated drawing, since this can add too much// overhead to the process.if (!ActivityManager.isHighEndGfx()) {ThreadedRenderer.disable(false);}}if (mProfiler.profileFd != null) {mProfiler.startProfiling();}// If the app is Honeycomb MR1 or earlier, switch its AsyncTask// implementation to use the pool executor. Normally, we use the// serialized executor as the default. This has to happen in the// main thread so the main looper is set right.if (data.appInfo.targetSdkVersion <= android.os.Build.VERSION_CODES.HONEYCOMB_MR1) {AsyncTask.setDefaultExecutor(AsyncTask.THREAD_POOL_EXECUTOR);}Message.updateCheckRecycle(data.appInfo.targetSdkVersion);/** Before spawning a new process, reset the time zone to be the system time zone.* This needs to be done because the system time zone could have changed after the* the spawning of this process. Without doing this this process would have the incorrect* system time zone.*/TimeZone.setDefault(null);/** Set the LocaleList. This may change once we create the App Context.*/LocaleList.setDefault(data.config.getLocales());synchronized (mResourcesManager) {/** Update the system configuration since its preloaded and might not* reflect configuration changes. The configuration object passed* in AppBindData can be safely assumed to be up to date*/mResourcesManager.applyConfigurationToResourcesLocked(data.config, data.compatInfo);mCurDefaultDisplayDpi = data.config.densityDpi;// This calls mResourcesManager so keep it within the synchronized block.applyCompatConfiguration(mCurDefaultDisplayDpi);}data.info = getPackageInfoNoCheck(data.appInfo, data.compatInfo);/*** Switch this process to density compatibility mode if needed.*/if ((data.appInfo.flags&ApplicationInfo.FLAG_SUPPORTS_SCREEN_DENSITIES)== 0) {mDensityCompatMode = true;Bitmap.setDefaultDensity(DisplayMetrics.DENSITY_DEFAULT);}updateDefaultDensity();final String use24HourSetting = mCoreSettings.getString(Settings.System.TIME_12_24);Boolean is24Hr = null;if (use24HourSetting != null) {is24Hr = "24".equals(use24HourSetting) ? Boolean.TRUE : Boolean.FALSE;}// null : use locale default for 12/24 hour formatting,// false : use 12 hour format,// true : use 24 hour format.DateFormat.set24HourTimePref(is24Hr);View.mDebugViewAttributes =mCoreSettings.getInt(Settings.Global.DEBUG_VIEW_ATTRIBUTES, 0) != 0;/*** For system applications on userdebug/eng builds, log stack* traces of disk and network access to dropbox for analysis.*/if ((data.appInfo.flags &(ApplicationInfo.FLAG_SYSTEM |ApplicationInfo.FLAG_UPDATED_SYSTEM_APP)) != 0) {StrictMode.conditionallyEnableDebugLogging();}/*** For apps targetting Honeycomb or later, we don't allow network usage* on the main event loop / UI thread. This is what ultimately throws* {@link NetworkOnMainThreadException}.*/if (data.appInfo.targetSdkVersion >= Build.VERSION_CODES.HONEYCOMB) {StrictMode.enableDeathOnNetwork();}/*** For apps targetting N or later, we don't allow file:// Uri exposure.* This is what ultimately throws {@link FileUriExposedException}.*/if (data.appInfo.targetSdkVersion >= Build.VERSION_CODES.N) {StrictMode.enableDeathOnFileUriExposure();}// We deprecated Build.SERIAL and only apps that target pre NMR1// SDK can see it. Since access to the serial is now behind a// permission we push down the value and here we fix it up// before any app code has been loaded.try {Field field = Build.class.getDeclaredField("SERIAL");field.setAccessible(true);field.set(Build.class, data.buildSerial);} catch (NoSuchFieldException | IllegalAccessException e) {/* ignore */}if (data.debugMode != ApplicationThreadConstants.DEBUG_OFF) {// XXX should have option to change the port.Debug.changeDebugPort(8100);if (data.debugMode == ApplicationThreadConstants.DEBUG_WAIT) {Slog.w(TAG, "Application " + data.info.getPackageName()+ " is waiting for the debugger on port 8100...");IActivityManager mgr = ActivityManager.getService();try {mgr.showWaitingForDebugger(mAppThread, true);} catch (RemoteException ex) {throw ex.rethrowFromSystemServer();}Debug.waitForDebugger();try {mgr.showWaitingForDebugger(mAppThread, false);} catch (RemoteException ex) {throw ex.rethrowFromSystemServer();}} else {Slog.w(TAG, "Application " + data.info.getPackageName()+ " can be debugged on port 8100...");}}// Allow application-generated systrace messages if we're debuggable.boolean isAppDebuggable = (data.appInfo.flags & ApplicationInfo.FLAG_DEBUGGABLE) != 0;Trace.setAppTracingAllowed(isAppDebuggable);if (isAppDebuggable && data.enableBinderTracking) {Binder.enableTracing();}/*** Initialize the default http proxy in this process for the reasons we set the time zone.*/Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "Setup proxies");final IBinder b = ServiceManager.getService(Context.CONNECTIVITY_SERVICE);if (b != null) {// In pre-boot mode (doing initial launch to collect password), not// all system is up. This includes the connectivity service, so don't// crash if we can't get it.final IConnectivityManager service = IConnectivityManager.Stub.asInterface(b);try {final ProxyInfo proxyInfo = service.getProxyForNetwork(null);Proxy.setHttpProxySystemProperty(proxyInfo);} catch (RemoteException e) {Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);throw e.rethrowFromSystemServer();}}Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);// Instrumentation info affects the class loader, so load it before// setting up the app context.final InstrumentationInfo ii;if (data.instrumentationName != null) {try {ii = new ApplicationPackageManager(null, getPackageManager()).getInstrumentationInfo(data.instrumentationName, 0);} catch (PackageManager.NameNotFoundException e) {throw new RuntimeException("Unable to find instrumentation info for: " + data.instrumentationName);}mInstrumentationPackageName = ii.packageName;mInstrumentationAppDir = ii.sourceDir;mInstrumentationSplitAppDirs = ii.splitSourceDirs;mInstrumentationLibDir = getInstrumentationLibrary(data.appInfo, ii);mInstrumentedAppDir = data.info.getAppDir();mInstrumentedSplitAppDirs = data.info.getSplitAppDirs();mInstrumentedLibDir = data.info.getLibDir();} else {ii = null;}final ContextImpl appContext = ContextImpl.createAppContext(this, data.info);updateLocaleListFromAppContext(appContext,mResourcesManager.getConfiguration().getLocales());if (!Process.isIsolated() && !"android".equals(appContext.getPackageName())) {// This cache location probably points at credential-encrypted// storage which may not be accessible yet; assign it anyway instead// of pointing at device-encrypted storage.final File cacheDir = appContext.getCacheDir();if (cacheDir != null) {// Provide a usable directory for temporary filesSystem.setProperty("java.io.tmpdir", cacheDir.getAbsolutePath());} else {Log.v(TAG, "Unable to initialize \"java.io.tmpdir\" property "+ "due to missing cache directory");}// Setup a location to store generated/compiled graphics code.final Context deviceContext = appContext.createDeviceProtectedStorageContext();final File codeCacheDir = deviceContext.getCodeCacheDir();if (codeCacheDir != null) {setupGraphicsSupport(appContext, codeCacheDir);} else {Log.e(TAG, "Unable to setupGraphicsSupport due to missing code-cache directory");}}// If we use profiles, setup the dex reporter to notify package manager// of any relevant dex loads. The idle maintenance job will use the information// reported to optimize the loaded dex files.// Note that we only need one global reporter per app.// Make sure we do this before calling onCreate so that we can capture the// complete application startup.if (SystemProperties.getBoolean("dalvik.vm.usejitprofiles", false)) {BaseDexClassLoader.setReporter(DexLoadReporter.getInstance());}// Install the Network Security Config Provider. This must happen before the application// code is loaded to prevent issues with instances of TLS objects being created before// the provider is installed.Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "NetworkSecurityConfigProvider.install");NetworkSecurityConfigProvider.install(appContext);Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);// Continue loading instrumentation.if (ii != null) {final ApplicationInfo instrApp = new ApplicationInfo();ii.copyTo(instrApp);instrApp.initForUser(UserHandle.myUserId());final LoadedApk pi = getPackageInfo(instrApp, data.compatInfo,appContext.getClassLoader(), false, true, false);final ContextImpl instrContext = ContextImpl.createAppContext(this, pi);try {final ClassLoader cl = instrContext.getClassLoader();mInstrumentation = (Instrumentation)cl.loadClass(data.instrumentationName.getClassName()).newInstance();} catch (Exception e) {throw new RuntimeException("Unable to instantiate instrumentation "+ data.instrumentationName + ": " + e.toString(), e);}final ComponentName component = new ComponentName(ii.packageName, ii.name);mInstrumentation.init(this, instrContext, appContext, component,data.instrumentationWatcher, data.instrumentationUiAutomationConnection);if (mProfiler.profileFile != null && !ii.handleProfiling&& mProfiler.profileFd == null) {mProfiler.handlingProfiling = true;final File file = new File(mProfiler.profileFile);file.getParentFile().mkdirs();Debug.startMethodTracing(file.toString(), 8 * 1024 * 1024);}} else {mInstrumentation = new Instrumentation();}if ((data.appInfo.flags&ApplicationInfo.FLAG_LARGE_HEAP) != 0) {dalvik.system.VMRuntime.getRuntime().clearGrowthLimit();} else {// Small heap, clamp to the current growth limit and let the heap release// pages after the growth limit to the non growth limit capacity. b/18387825dalvik.system.VMRuntime.getRuntime().clampGrowthLimit();}// Allow disk access during application and provider setup. This could// block processing ordered broadcasts, but later processing would// probably end up doing the same disk access.final StrictMode.ThreadPolicy savedPolicy = StrictMode.allowThreadDiskWrites();try {// If the app is being launched for full backup or restore, bring it up in// a restricted environment with the base application class.// ★ 创建 Application // ★ 此时调用 Application 的 attachBaseContext 方法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// ★ 在此处创建 ContentProvider if (!data.restrictedBackupMode) {if (!ArrayUtils.isEmpty(data.providers)) {// ★ 安装 ContentProviderinstallContentProviders(app, data.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);}}// Do this after providers, since instrumentation tests generally start their// test thread at this point, and we don't want that racing.try {// ★ 此处调用 Application 的 onCreate 方法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);}// Preload fonts resourcesFontsContract.setApplicationContextForResources(appContext);try {final ApplicationInfo info =getPackageManager().getApplicationInfo(data.appInfo.packageName,PackageManager.GET_META_DATA /*flags*/,UserHandle.myUserId());if (info.metaData != null) {final int preloadedFontsResource = info.metaData.getInt(ApplicationInfo.METADATA_PRELOADED_FONTS, 0);if (preloadedFontsResource != 0) {data.info.mResources.preloadFonts(preloadedFontsResource);}}} catch (RemoteException e) {throw e.rethrowFromSystemServer();}}// ★ 传入两个参数 , // ★ Context context : 之前创建的 Application 上下文对象 , // 这个 Application 对象是替换前的 代理 Application 对象 , // 是在 AndroidManifest.xml 中的 application 节点信息 , // ★ List<ProviderInfo> providers , 这里的 ProviderInfo 集合 // ★ 是为生成多个 ContentProvider 准备的 // ★ ProviderInfo 与 ApplicationInfo 是相同的// ★ ApplicationInfo 是 AndroidManifest.xml 中的 application 节点信息 // ★ ProviderInfo 是 AndroidManifest.xml 中的 provider 节点信息 private void installContentProviders(Context context, List<ProviderInfo> providers) {// ★ 存放创建的多个 ContentProvider final ArrayList<ContentProviderHolder> results = new ArrayList<>();// ★ 创建多个 ContentProvider for (ProviderInfo cpi : providers) {if (DEBUG_PROVIDER) {StringBuilder buf = new StringBuilder(128);buf.append("Pub ");buf.append(cpi.authority);buf.append(": ");buf.append(cpi.name);Log.i(TAG, buf.toString());}// ★ 注意这里 installProvider 的第一个参数是 ProxyApplication 类型的ContentProviderHolder cph = installProvider(context, null, cpi,false /*noisy*/, true /*noReleaseNeeded*/, true /*stable*/);if (cph != null) {cph.noReleaseNeeded = true;results.add(cph);}}try {ActivityManager.getService().publishContentProviders(getApplicationThread(), results);} catch (RemoteException ex) {throw ex.rethrowFromSystemServer();}}/*** Installs the provider.** Providers that are local to the process or that come from the system server* may be installed permanently which is indicated by setting noReleaseNeeded to true.* Other remote providers are reference counted. The initial reference count* for all reference counted providers is one. Providers that are not reference* counted do not have a reference count (at all).** This method detects when a provider has already been installed. When this happens,* it increments the reference count of the existing provider (if appropriate)* and returns the existing provider. This can happen due to concurrent* attempts to acquire the same provider.*/private ContentProviderHolder installProvider(Context context,ContentProviderHolder holder, ProviderInfo info,boolean noisy, boolean noReleaseNeeded, boolean stable) {// ★ 声明 ContentProvider ContentProvider localProvider = null;IContentProvider provider;if (holder == null || holder.provider == null) {if (DEBUG_PROVIDER || noisy) {Slog.d(TAG, "Loading provider " + info.authority + ": "+ info.name);}Context c = null;ApplicationInfo ai = info.applicationInfo;if (context.getPackageName().equals(ai.packageName)) {c = context;} else if (mInitialApplication != null &&mInitialApplication.getPackageName().equals(ai.packageName)) {c = mInitialApplication;} else {try {c = context.createPackageContext(ai.packageName,Context.CONTEXT_INCLUDE_CODE);} catch (PackageManager.NameNotFoundException e) {// Ignore}}if (c == null) {Slog.w(TAG, "Unable to get context for package " +ai.packageName +" while loading content provider " +info.name);return null;}if (info.splitName != null) {try {c = c.createContextForSplit(info.splitName);} catch (NameNotFoundException e) {throw new RuntimeException(e);}}try {final java.lang.ClassLoader cl = c.getClassLoader();// ★ 反射创建 ContentProvider 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.// ★ 创建 ContentProvider 之后 , 调用了 attachInfo 函数 // 注意此处与 Activity , Service , BrocastReceiver 不同 , // 这三个组件创建后调用的是 attach 函数localProvider.attachInfo(c, info);} catch (java.lang.Exception e) {if (!mInstrumentation.onException(null, e)) {throw new RuntimeException("Unable to get provider " + info.name+ ": " + e.toString(), e);}return null;}} else {provider = holder.provider;if (DEBUG_PROVIDER) Slog.v(TAG, "Installing external provider " + info.authority + ": "+ info.name);}ContentProviderHolder retHolder;synchronized (mProviderMap) {if (DEBUG_PROVIDER) Slog.v(TAG, "Checking to add " + provider+ " / " + info.name);IBinder jBinder = provider.asBinder();if (localProvider != null) {ComponentName cname = new ComponentName(info.packageName, info.name);ProviderClientRecord pr = mLocalProvidersByName.get(cname);if (pr != null) {if (DEBUG_PROVIDER) {Slog.v(TAG, "installProvider: lost the race, "+ "using existing local provider");}provider = pr.mProvider;} else {holder = new ContentProviderHolder(info);holder.provider = provider;holder.noReleaseNeeded = true;pr = installProviderAuthoritiesLocked(provider, localProvider, holder);mLocalProviders.put(jBinder, pr);mLocalProvidersByName.put(cname, pr);}retHolder = pr.mHolder;} else {ProviderRefCount prc = mProviderRefCountMap.get(jBinder);if (prc != null) {if (DEBUG_PROVIDER) {Slog.v(TAG, "installProvider: lost the race, updating ref count");}// We need to transfer our new reference to the existing// ref count, releasing the old one... but only if// release is needed (that is, it is not running in the// system process).if (!noReleaseNeeded) {incProviderRefLocked(prc, stable);try {ActivityManager.getService().removeContentProvider(holder.connection, stable);} catch (RemoteException e) {//do nothing content provider object is dead any way}}} else {ProviderClientRecord client = installProviderAuthoritiesLocked(provider, localProvider, holder);if (noReleaseNeeded) {prc = new ProviderRefCount(holder, client, 1000, 1000);} else {prc = stable? new ProviderRefCount(holder, client, 1, 0): new ProviderRefCount(holder, client, 0, 1);}mProviderRefCountMap.put(jBinder, prc);}retHolder = prc.holder;}}return retHolder;}}

参考路径 : frameworks/base/core/java/android/app/ActivityThread.java

八、 Instrumentation 涉及源码

---

Instrumentation 中创建 Activity 的 newActivity 方法 ;

public class Instrumentation {/*** Perform instantiation of an {@link Activity} object. This method is intended for use with* unit tests, such as android.test.ActivityUnitTestCase. The activity will be useable* locally but will be missing some of the linkages necessary for use within the system.* * @param clazz The Class of the desired Activity* @param context The base context for the activity to use* @param token The token for this activity to communicate with* @param application The application object (if any)* @param intent The intent that started this Activity* @param info ActivityInfo from the manifest* @param title The title, typically retrieved from the ActivityInfo record* @param parent The parent Activity (if any)* @param id The embedded Id (if any)* @param lastNonConfigurationInstance Arbitrary object that will be* available via {@link Activity#getLastNonConfigurationInstance()* Activity.getLastNonConfigurationInstance()}.* @return Returns the instantiated activity* @throws InstantiationException* @throws IllegalAccessException*/public Activity newActivity(Class<?> clazz, Context context, IBinder token, Application application, Intent intent, ActivityInfo info, CharSequence title, Activity parent, String id,Object lastNonConfigurationInstance) throws InstantiationException, IllegalAccessException {Activity activity = (Activity)clazz.newInstance();ActivityThread aThread = null;activity.attach(context, aThread, this, token, 0 /* ident */, application, intent,info, title, parent, id,(Activity.NonConfigurationInstances)lastNonConfigurationInstance,new Configuration(), null /* referrer */, null /* voiceInteractor */,null /* window */, null /* activityConfigCallback */);return activity;}}

参考路径 : frameworks/base/core/java/android/app/Instrumentation.java

九、 LoadedApk 涉及源码

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LoadedApk 中相关源码 :

public final class LoadedApk {public Application makeApplication(boolean forceDefaultAppClass,Instrumentation instrumentation) {// ★ 如果之前创建过 Application , 就直接使用 if (mApplication != null) {return mApplication;}Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "makeApplication");Application app = null;String appClass = mApplicationInfo.className;if (forceDefaultAppClass || (appClass == null)) {appClass = "android.app.Application";}try {java.lang.ClassLoader cl = getClassLoader();if (!mPackageName.equals("android")) {Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER,"initializeJavaContextClassLoader");initializeJavaContextClassLoader();Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);}ContextImpl appContext = ContextImpl.createAppContext(mActivityThread, this);app = mActivityThread.mInstrumentation.newApplication(cl, appClass, appContext);appContext.setOuterContext(app);} catch (Exception e) {if (!mActivityThread.mInstrumentation.onException(app, e)) {Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);throw new RuntimeException("Unable to instantiate application " + appClass+ ": " + e.toString(), e);}}mActivityThread.mAllApplications.add(app);mApplication = app;if (instrumentation != null) {try {instrumentation.callApplicationOnCreate(app);} catch (Exception e) {if (!instrumentation.onException(app, e)) {Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);throw new RuntimeException("Unable to create application " + app.getClass().getName()+ ": " + e.toString(), e);}}}// Rewrite the R 'constants' for all library apks.SparseArray<String> packageIdentifiers = getAssets().getAssignedPackageIdentifiers();final int N = packageIdentifiers.size();for (int i = 0; i < N; i++) {final int id = packageIdentifiers.keyAt(i);if (id == 0x01 || id == 0x7f) {continue;}rewriteRValues(getClassLoader(), packageIdentifiers.valueAt(i), id);}Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);return app;}}

参考路径 : frameworks/base/core/java/android/app/LoadedApk.java

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