android----ServiceManager
serviceManager
在c++层如何使用serviceManager
frameworks\base\services\camera\tests\CameraServiceTest,示例代码如下：
sp<ICameraService>getCameraService(){
//取得serviceManager
sp<IServiceManager>sm=defaultServiceManager();
ASSERT(sm!=0);
sp<IBinder>binder=sm->getService(String16("media.camera"));
ASSERT(binder!=0);
sp<ICameraService>cs=interface_cast<ICameraService>(binder);
ASSERT(cs!=0);
returncs;
}
\frameworks\base\services\java\com\android\server\am
在java层使用serviceManager
\frameworks\base\services\java\com\android\server\am\
AtcitiveyManagerService.java示例代码：
publicstaticvoidsetSystemProcess(){
try{
//以下语句相当于上面c++层的，
//defaultServiceManager()->addService()
ActivityManagerServicem=mSelf;
ServiceManager.addService("activity",m);
ServiceManager.addService("meminfo",newMemBinder(m));
if(MONITOR_CPU_USAGE){
ServiceManager.addService("cpuinfo",newCpuBinder
(m));
}
ServiceManager.addService("activity.broadcasts",new
BroadcastsBinder(m));
ServiceManager.addService("activity.services",new
ServicesBinder(m));
ServiceManager.addService("activity.senders",new
SendersBinder(m));
ServiceManager.addService("activity.providers",
newProvidersBinder(m));
ServiceManager.addService("permission",
newPermissionController(m));
ApplicationInfoinfo=
mSelf.mContext.getPackageManager
().getApplicationInfo(
"android",
PackageManager.GET_SHARED_LIBRARY_FILES);
synchronized(mSelf){
ProcessRecordapp=mSelf.newProcessRecordLocked(
mSystemThread.getApplicationThread(),
info,
info.processName);
app.persistent=true;
app.pid=Process.myPid();
app.maxAdj=SYSTEM_ADJ;
mSelf.mProcessNames.put(app.processName,
app.info.uid,app);
synchronized(mSelf.mPidsSelfLocked){
mSelf.mPidsSelfLocked.put(app.pid,app);
}
mSelf.updateLRUListLocked(app,true);
}
}catch(PackageManager.NameNotFoundExceptione){
thrownewRuntimeException("Unabletofindandroidsystem
package",e);
}
}
serviceManager在c++层
\frameworks\base\libs\binder
IServiceManager.cpp文件部分代码如下：
sp<IServiceManager>defaultServiceManager()
{
if(gDefaultServiceManager!=NULL)returngDefaultServiceManager;
{
AutoMutex_l(gDefaultServiceManagerLock);
if(gDefaultServiceManager==NULL){
gDefaultServiceManager=interface_cast<IServiceManager>(
//产生一个bpServicManager对象，提代iServiceManager接口,让
defaultServiceManager来回调这个接口
ProcessState::self()->getContextObject(NULL));
}
}
returngDefaultServiceManager;
}
serviceManager在java层
\frameworks\base\core\java\android\os
publicfinalclassServiceManager{
.....
privatestaticIServiceManagergetIServiceManager(){
if(sServiceManager!=null){
returnsServiceManager;
}
//Findtheservicemanager
//产生一个serviceManagerProxy,提供IServiceManager接口，
getiServiceManager回调IServiceManager接口
sServiceManager=ServiceManagerNative.asInterface
(BinderInternal.getContextObject());
returnsServiceManager;
}
publicstaticIBindergetService(Stringname){
try{
IBinderservice=sCache.get(name);
if(service!=null){
returnservice;
}else{
//调用底层serviceManager
returngetIServiceManager().getService(name);
}
}catch(RemoteExceptione){
Log.e(TAG,"erroringetService",e);}
returnnull;
}
publicstaticvoidaddService(Stringname,IBinderservice){
try{
//调用底层serviceManager
getIServiceManager().addService(name,service);
}catch(RemoteExceptione){
Log.e(TAG,"errorinaddService",e);
}
}
.....
}