contexthub: [android.hardware.location.IContextHubService]
这里系统服务指继承于SystemService的service.这里服务没有显示调用ServiceManager.addService
而是通过publishBinderService。
traceBeginAndSlog("StartContextHubSystemService");
mSystemServiceManager.startService(ContextHubSystemService.class);
traceEnd();
这里先不关心注册的事，先看下mSystemServiceManager.startService
frameworks/base/services/core/java/com/android/server/SystemServiceManager.java
/**
* Creates and starts a system service. The class must be a subclass of
* {@link com.android.server.SystemService}.
*
* @param serviceClass A Java class that implements the SystemService interface.
* @return The service instance, never null.
* @throws RuntimeException if the service fails to start.
*/
@SuppressWarnings("unchecked")
public <T extends SystemService> T startService(Class<T> serviceClass) {
try {
final String name = serviceClass.getName();
Slog.i(TAG, "Starting " + name);
Trace.traceBegin(Trace.TRACE_TAG_SYSTEM_SERVER, "StartService " + name);
// Create the service.
if (!SystemService.class.isAssignableFrom(serviceClass)) {
throw new RuntimeException("Failed to create " + name
+ ": service must extend " + SystemService.class.getName());
}
final T service;
try {
Constructor<T> constructor = serviceClass.getConstructor(Context.class);
service = constructor.newInstance(mContext);
}
startService(service);
return service;
}
}
public void startService(@NonNull final SystemService service) {
// Register it.
mServices.add(service);
// Start it.
try {
service.onStart();
}
}
最终调用到service的onStart
系统服务都继承基类
frameworks/base/services/core/java/com/android/server/SystemService.java
/**
* The base class for services running in the system process. Override and implement
* the lifecycle event callback methods as needed.
*
* The lifecycle of a SystemService:
*
* The constructor is called and provided with the system {@link Context}
* to initialize the system service.
* {onStart()} is called to get the service running. The service should
* publish its binder interface at this point using
* {publishBinderService(String, IBinder)}. It may also publish additional
* local interfaces that other services within the system server may use to access
* privileged internal functions.
* Then {onBootPhase(int)} is called as many times as there are boot phases
* until {PHASE_BOOT_COMPLETED} 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.
*/
ContextHubService看上去怪怪的，看下dropbox的：
public final class DropBoxManagerService extends SystemService {
@Override
public void onStart() {/service的名字是这里传入的
publishBinderService(Context.DROPBOX_SERVICE, mStub);
}
}
SystemSeriveManager: ServiceManager的区别
SystemSeriveManager用于管理继承于SystemService的service
SystemService通过函数基类函数 publishBinderService ->调用
ServiceManager.addService(name, service, allowIsolated);
和ServiceManager发生关联。
ServiceManager 是servicemanager的一个封装通过publict static函数调用addService
这样service list可以看到service.