/** Returns the singleton, or throws if NFC is not available. */
static synchronized NfcAdapter getSingleton() {
if (!sIsInitialized) {
sIsInitialized = true;
/* is this device meant to have NFC */
if (!hasNfcFeature()) {
Log.v(TAG, "this device does not have NFC support");
throw new UnsupportedOperationException();
}
sService = getServiceInterface();
if (sService == null) {
Log.e(TAG, "could not retrieve NFC service");
throw new UnsupportedOperationException();
}
try {
sTagService = sService.getNfcTagInterface();
} catch (RemoteException e) {
Log.e(TAG, "could not retrieve NFC Tag service");
throw new UnsupportedOperationException();
}
sSingleton = new NfcAdapter();
}
if (sSingleton == null) {
throw new UnsupportedOperationException();
}
return sSingleton;
}
/**
* NFC service dead - attempt best effort recovery
*
* @hide
*/
public void attemptDeadServiceRecovery(Exception e) {
Log.e(TAG, "NFC service dead - attempting to recover", e);
INfcAdapter service = getServiceInterface();
if (service == null) {
Log.e(TAG, "could not retrieve NFC service during service recovery");
// nothing more can be done now, sService is still stale, we'll hit
// this recovery path again later
return;
}
// assigning to sService is not thread-safe, but this is best-effort code
// and on a well-behaved system should never happen
sService = service;
try {
sTagService = service.getNfcTagInterface();
} catch (RemoteException ee) {
Log.e(TAG, "could not retrieve NFC tag service during service recovery");
// nothing more can be done now, sService is still stale, we'll hit
// this recovery path again later
}
return;
}
