| /* |
| * Copyright (C) 2013 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.server; |
| |
| import android.content.Context; |
| import android.os.IBinder; |
| import android.os.ServiceManager; |
| |
| /** |
| * The base class for services running in the system process. Override and implement |
| * the lifecycle event callback methods as needed. |
| * <p> |
| * The lifecycle of a SystemService: |
| * </p><ul> |
| * <li>The constructor is called and provided with the system {@link Context} |
| * to initialize the system service. |
| * <li>{@link #onStart()} is called to get the service running. The service should |
| * publish its binder interface at this point using |
| * {@link #publishBinderService(String, IBinder)}. It may also publish additional |
| * local interfaces that other services within the system server may use to access |
| * privileged internal functions. |
| * <li>Then {@link #onBootPhase(int)} is called as many times as there are boot phases |
| * until {@link #PHASE_BOOT_COMPLETE} is sent, which is the last boot phase. Each phase |
| * is an opportunity to do special work, like acquiring optional service dependencies, |
| * waiting to see if SafeMode is enabled, or registering with a service that gets |
| * started after this one. |
| * </ul><p> |
| * NOTE: All lifecycle methods are called from the system server's main looper thread. |
| * </p> |
| * |
| * {@hide} |
| */ |
| public abstract class SystemService { |
| /* |
| * Boot Phases |
| */ |
| public static final int PHASE_WAIT_FOR_DEFAULT_DISPLAY = 100; // maybe should be a dependency? |
| |
| /** |
| * After receiving this boot phase, services can obtain lock settings data. |
| */ |
| public static final int PHASE_LOCK_SETTINGS_READY = 480; |
| |
| /** |
| * After receiving this boot phase, services can safely call into core system services |
| * such as the PowerManager or PackageManager. |
| */ |
| public static final int PHASE_SYSTEM_SERVICES_READY = 500; |
| |
| /** |
| * After receiving this boot phase, services can broadcast Intents. |
| */ |
| public static final int PHASE_ACTIVITY_MANAGER_READY = 550; |
| |
| /** |
| * After receiving this boot phase, services can start/bind to third party apps. |
| * Apps will be able to make Binder calls into services at this point. |
| */ |
| public static final int PHASE_THIRD_PARTY_APPS_CAN_START = 600; |
| |
| /** |
| * After receiving this boot phase, services can allow user interaction with the device. |
| * This phase occurs when boot has completed and the home application has started. |
| * System services may prefer to listen to this phase rather than registering a |
| * broadcast receiver for ACTION_BOOT_COMPLETED to reduce overall latency. |
| */ |
| public static final int PHASE_BOOT_COMPLETED = 1000; |
| |
| private final Context mContext; |
| |
| /** |
| * Initializes the system service. |
| * <p> |
| * Subclasses must define a single argument constructor that accepts the context |
| * and passes it to super. |
| * </p> |
| * |
| * @param context The system server context. |
| */ |
| public SystemService(Context context) { |
| mContext = context; |
| } |
| |
| /** |
| * Gets the system context. |
| */ |
| public final Context getContext() { |
| return mContext; |
| } |
| |
| /** |
| * Returns true if the system is running in safe mode. |
| * TODO: we should define in which phase this becomes valid |
| */ |
| public final boolean isSafeMode() { |
| return getManager().isSafeMode(); |
| } |
| |
| /** |
| * Called when the dependencies listed in the @Service class-annotation are available |
| * and after the chosen start phase. |
| * When this method returns, the service should be published. |
| */ |
| public abstract void onStart(); |
| |
| /** |
| * Called on each phase of the boot process. Phases before the service's start phase |
| * (as defined in the @Service annotation) are never received. |
| * |
| * @param phase The current boot phase. |
| */ |
| public void onBootPhase(int phase) {} |
| |
| /** |
| * Called when a new user is starting, for system services to initialize any per-user |
| * state they maintain for running users. |
| * @param userHandle The identifier of the user. |
| */ |
| public void onStartUser(int userHandle) {} |
| |
| /** |
| * Called when switching to a different foreground user, for system services that have |
| * special behavior for whichever user is currently in the foreground. This is called |
| * before any application processes are aware of the new user. |
| * @param userHandle The identifier of the user. |
| */ |
| public void onSwitchUser(int userHandle) {} |
| |
| /** |
| * Called when an existing user is stopping, for system services to finalize any per-user |
| * state they maintain for running users. This is called prior to sending the SHUTDOWN |
| * broadcast to the user; it is a good place to stop making use of any resources of that |
| * user (such as binding to a service running in the user). |
| * @param userHandle The identifier of the user. |
| */ |
| public void onStopUser(int userHandle) {} |
| |
| /** |
| * Called when an existing user is stopping, for system services to finalize any per-user |
| * state they maintain for running users. This is called after all application process |
| * teardown of the user is complete. |
| * @param userHandle The identifier of the user. |
| */ |
| public void onCleanupUser(int userHandle) {} |
| |
| /** |
| * Publish the service so it is accessible to other services and apps. |
| */ |
| protected final void publishBinderService(String name, IBinder service) { |
| publishBinderService(name, service, false); |
| } |
| |
| /** |
| * Publish the service so it is accessible to other services and apps. |
| */ |
| protected final void publishBinderService(String name, IBinder service, |
| boolean allowIsolated) { |
| ServiceManager.addService(name, service, allowIsolated); |
| } |
| |
| /** |
| * Get a binder service by its name. |
| */ |
| protected final IBinder getBinderService(String name) { |
| return ServiceManager.getService(name); |
| } |
| |
| /** |
| * Publish the service so it is only accessible to the system process. |
| */ |
| protected final <T> void publishLocalService(Class<T> type, T service) { |
| LocalServices.addService(type, service); |
| } |
| |
| /** |
| * Get a local service by interface. |
| */ |
| protected final <T> T getLocalService(Class<T> type) { |
| return LocalServices.getService(type); |
| } |
| |
| private SystemServiceManager getManager() { |
| return LocalServices.getService(SystemServiceManager.class); |
| } |
| } |