app/src/main/java/de/dhbwloe/campusapp/nfcreader/cardreader/Readers.java

   1 /*
   2  * Readers.java
   3  *
   4  * Copyright (C) 2014 Jakob Wenzel
   5  *
   6  * Authors:
   7  * Jakob Wenzel <jakobwenzel92@gmail.com>
   8  *
   9  * This program is free software: you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation, either version 3 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21  */
  22
  23 package de.dhbwloe.campusapp.nfcreader.cardreader;
  24
  25 import android.nfc.Tag;
  26 import android.nfc.tech.IsoDep;
  27 import android.util.Log;
  28
  29 import com.codebutler.farebot.card.desfire.DesfireException;
  30 import com.codebutler.farebot.card.desfire.DesfireProtocol;
  31
  32 import java.io.IOException;
  33
  34 public class Readers implements ICardReader {
  35         private static final String TAG = Readers.class.getName();
  36         private static Readers instance;
  37         private ICardReader[] readers = new ICardReader[]{
  38                         new MagnaCartaReader(),
  39                         new IntercardReader()};
  40
  41
  42         @Override
  43         public NfcCardData readCard(DesfireProtocol card) throws DesfireException {
  44                 Log.i(TAG, "Trying all readers");
  45                 for (ICardReader reader : readers) {
  46                         Log.i(TAG, "Trying " + reader.getClass().getSimpleName());
  47                         NfcCardData val = reader.readCard(card);
  48                         if (val!=null)
  49                                 return val;
  50                 }
  51                 return null;
  52         }
  53
  54
  55         public NfcCardData readTag(Tag tag) throws DesfireException {
  56                 Log.i(TAG, "Loading tag");
  57                 IsoDep tech = IsoDep.get(tag);
  58
  59                 try {
  60                         tech.connect();
  61                 } catch (IOException e) {
  62                         //Tag was removed. We fail silently.
  63                         e.printStackTrace();
  64                         return null;
  65                 }
  66
  67                 try {
  68                         DesfireProtocol desfireTag = new DesfireProtocol(tech);
  69
  70
  71                         //Android has a Bug on Devices using a Broadcom NFC chip. See
  72                         // http://code.google.com/p/android/issues/detail?id=58773
  73                         //A Workaround is to connected to the tag, issue a dummy operation and then reconnect...
  74                         try {
  75                                 desfireTag.selectApp(0);
  76                         }catch (ArrayIndexOutOfBoundsException e) {
  77                                 //Exception occurs because the actual response is shorter than the error response
  78                                 Log.i(TAG, "Broadcom workaround was needed");
  79                         }
  80
  81                         tech.close();
  82                         tech.connect();
  83
  84                         NfcCardData val = Readers.getInstance().readCard(desfireTag);
  85                         return val;
  86                 } catch (IOException e) {
  87                         //This can only happen on tag close. we ignore this.
  88                         e.printStackTrace();
  89                         return null;
  90                 } finally {
  91                         if (tech.isConnected())
  92                                 try {
  93                                         tech.close();
  94                                 } catch (IOException e) {
  95                                         e.printStackTrace();
  96                                 }
  97                 }
  98
  99         }
 100
 101         public static Readers getInstance() {
 102                 if (instance == null)
 103                         instance = new Readers();
 104                 return instance;
 105         }
 106 }