/* * Copyright (C) 2011 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.nfc_extras; import java.util.HashMap; import android.content.Context; import android.nfc.INfcAdapterExtras; import android.nfc.NfcAdapter; import android.os.RemoteException; import android.util.Log; /** * Provides additional methods on an {@link NfcAdapter} for Card Emulation * and management of {@link NfcExecutionEnvironment}'s. * * There is a 1-1 relationship between an {@link NfcAdapterExtras} object and * a {@link NfcAdapter} object. */ public final class NfcAdapterExtras { private static final String TAG = "NfcAdapterExtras"; /** * Broadcast Action: an RF field ON has been detected. * *

This is an unreliable signal, and will be removed. *

* Requires the {@link android.Manifest.permission#WRITE_SECURE_SETTINGS} permission * to receive. */ public static final String ACTION_RF_FIELD_ON_DETECTED = "com.android.nfc_extras.action.RF_FIELD_ON_DETECTED"; /** * Broadcast Action: an RF field OFF has been detected. * *

This is an unreliable signal, and will be removed. *

* Requires the {@link android.Manifest.permission#WRITE_SECURE_SETTINGS} permission * to receive. */ public static final String ACTION_RF_FIELD_OFF_DETECTED = "com.android.nfc_extras.action.RF_FIELD_OFF_DETECTED"; // protected by NfcAdapterExtras.class, and final after first construction, // except for attemptDeadServiceRecovery() when NFC crashes - we accept a // best effort recovery private static INfcAdapterExtras sService; private static final CardEmulationRoute ROUTE_OFF = new CardEmulationRoute(CardEmulationRoute.ROUTE_OFF, null); // contents protected by NfcAdapterExtras.class private static final HashMap sNfcExtras = new HashMap(); private final NfcExecutionEnvironment mEmbeddedEe; private final CardEmulationRoute mRouteOnWhenScreenOn; private final NfcAdapter mAdapter; final String mPackageName; /** get service handles */ private static void initService(NfcAdapter adapter) { final INfcAdapterExtras service = adapter.getNfcAdapterExtrasInterface(); if (service != null) { // Leave stale rather than receive a null value. sService = service; } } /** * Get the {@link NfcAdapterExtras} for the given {@link NfcAdapter}. * *

* Requires the {@link android.Manifest.permission#WRITE_SECURE_SETTINGS} permission. * * @param adapter a {@link NfcAdapter}, must not be null * @return the {@link NfcAdapterExtras} object for the given {@link NfcAdapter} */ public static NfcAdapterExtras get(NfcAdapter adapter) { Context context = adapter.getContext(); if (context == null) { throw new UnsupportedOperationException( "You must pass a context to your NfcAdapter to use the NFC extras APIs"); } synchronized (NfcAdapterExtras.class) { if (sService == null) { initService(adapter); } NfcAdapterExtras extras = sNfcExtras.get(adapter); if (extras == null) { extras = new NfcAdapterExtras(adapter); sNfcExtras.put(adapter, extras); } return extras; } } private NfcAdapterExtras(NfcAdapter adapter) { mAdapter = adapter; mPackageName = adapter.getContext().getPackageName(); mEmbeddedEe = new NfcExecutionEnvironment(this); mRouteOnWhenScreenOn = new CardEmulationRoute(CardEmulationRoute.ROUTE_ON_WHEN_SCREEN_ON, mEmbeddedEe); } /** * Immutable data class that describes a card emulation route. */ public final static class CardEmulationRoute { /** * Card Emulation is turned off on this NfcAdapter. *

This is the default routing state after boot. */ public static final int ROUTE_OFF = 1; /** * Card Emulation is routed to {@link #nfcEe} only when the screen is on, * otherwise it is turned off. */ public static final int ROUTE_ON_WHEN_SCREEN_ON = 2; /** * A route such as {@link #ROUTE_OFF} or {@link #ROUTE_ON_WHEN_SCREEN_ON}. */ public final int route; /** * The {@link NFcExecutionEnvironment} that is Card Emulation is routed to. *

null if {@link #route} is {@link #ROUTE_OFF}, otherwise not null. */ public final NfcExecutionEnvironment nfcEe; public CardEmulationRoute(int route, NfcExecutionEnvironment nfcEe) { if (route == ROUTE_OFF && nfcEe != null) { throw new IllegalArgumentException("must not specifiy a NFC-EE with ROUTE_OFF"); } else if (route != ROUTE_OFF && nfcEe == null) { throw new IllegalArgumentException("must specifiy a NFC-EE for this route"); } this.route = route; this.nfcEe = nfcEe; } } /** * NFC service dead - attempt best effort recovery */ void attemptDeadServiceRecovery(Exception e) { Log.e(TAG, "NFC Adapter Extras dead - attempting to recover"); mAdapter.attemptDeadServiceRecovery(e); initService(mAdapter); } INfcAdapterExtras getService() { return sService; } /** * Get the routing state of this NFC EE. * *

* Requires the {@link android.Manifest.permission#WRITE_SECURE_SETTINGS} permission. */ public CardEmulationRoute getCardEmulationRoute() { try { int route = sService.getCardEmulationRoute(mPackageName); return route == CardEmulationRoute.ROUTE_OFF ? ROUTE_OFF : mRouteOnWhenScreenOn; } catch (RemoteException e) { attemptDeadServiceRecovery(e); return ROUTE_OFF; } } /** * Set the routing state of this NFC EE. * *

This routing state is not persisted across reboot. * *

* Requires the {@link android.Manifest.permission#WRITE_SECURE_SETTINGS} permission. * * @param route a {@link CardEmulationRoute} */ public void setCardEmulationRoute(CardEmulationRoute route) { try { sService.setCardEmulationRoute(mPackageName, route.route); } catch (RemoteException e) { attemptDeadServiceRecovery(e); } } /** * Get the {@link NfcExecutionEnvironment} that is embedded with the * {@link NfcAdapter}. * *

* Requires the {@link android.Manifest.permission#WRITE_SECURE_SETTINGS} permission. * * @return a {@link NfcExecutionEnvironment}, or null if there is no embedded NFC-EE */ public NfcExecutionEnvironment getEmbeddedExecutionEnvironment() { return mEmbeddedEe; } /** * Authenticate the client application. * * Some implementations of NFC Adapter Extras may require applications * to authenticate with a token, before using other methods. * * @param token a implementation specific token * @throws java.lang.SecurityException if authentication failed */ public void authenticate(byte[] token) { try { sService.authenticate(mPackageName, token); } catch (RemoteException e) { attemptDeadServiceRecovery(e); } } }