nfc-extras/java/com/android/nfc_extras/NfcAdapterExtras.java - platform/frameworks/base - Git at Google

 /*
  * 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.
      *
      * <p class="note">This is an unreliable signal, and will be removed.
      * <p class="note">
      * 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.
      *
      * <p class="note">This is an unreliable signal, and will be removed.
      * <p class="note">
      * 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<NfcAdapter, NfcAdapterExtras> 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}.
      *
      * <p class="note">
      * 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.
          * <p>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.
          * <p>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.
      *
      * <p class="note">
      * 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.
      *
      * <p>This routing state is not persisted across reboot.
      *
      * <p class="note">
      * 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}.
      *
      * <p class="note">
      * 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);
         }
     }

     /**
      * Returns the name of this adapter's driver.
      *
      * <p>Different NFC adapters may use different drivers.  This value is
      * informational and should not be parsed.
      *
      * @return the driver name, or empty string if unknown
      */
     public String getDriverName() {
         try {
             return sService.getDriverName(mPackageName);
         } catch (RemoteException e) {
             attemptDeadServiceRecovery(e);
             return "";
         }
     }
 }
	/*
	* 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.
	*
	* <p class="note">This is an unreliable signal, and will be removed.
	* <p class="note">
	* 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.
	*
	* <p class="note">This is an unreliable signal, and will be removed.
	* <p class="note">
	* 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<NfcAdapter, NfcAdapterExtras> 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}.
	*
	* <p class="note">
	* 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.
	* <p>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.
	* <p>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.
	*
	* <p class="note">
	* 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.
	*
	* <p>This routing state is not persisted across reboot.
	*
	* <p class="note">
	* 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}.
	*
	* <p class="note">
	* 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);
	}
	}

	/**
	* Returns the name of this adapter's driver.
	*
	* <p>Different NFC adapters may use different drivers. This value is
	* informational and should not be parsed.
	*
	* @return the driver name, or empty string if unknown
	*/
	public String getDriverName() {
	try {
	return sService.getDriverName(mPackageName);
	} catch (RemoteException e) {
	attemptDeadServiceRecovery(e);
	return "";
	}
	}
	}