NdefFormatable.java revision 4e21e1d21a877cce4db5ec8c5786604cc10f2d7e 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.nfc.tech;
18
19import android.nfc.ErrorCodes;
20import android.nfc.FormatException;
21import android.nfc.INfcTag;
22import android.nfc.NdefMessage;
23import android.nfc.NfcAdapter;
24import android.nfc.Tag;
25import android.os.RemoteException;
26import android.util.Log;
27
28import java.io.IOException;
29
30/**
31 * An interface to a {@link Tag} allowing to format the tag as NDEF.
32 *
33 * <p>You can acquire this kind of connection with {@link #get}.
34 *
35 * <p class="note"><strong>Note:</strong>
36 * Use of this class requires the {@link android.Manifest.permission#NFC}
37 * permission.
38 */
39public final class NdefFormatable extends BasicTagTechnology {
40    private static final String TAG = "NFC";
41
42    /**
43     * Returns an instance of this tech for the given tag. If the tag doesn't support
44     * this tech type null is returned.
45     *
46     * @param tag The tag to get the tech from
47     */
48    public static NdefFormatable get(Tag tag) {
49        if (!tag.hasTech(TagTechnology.NDEF_FORMATABLE)) return null;
50        try {
51            return new NdefFormatable(tag);
52        } catch (RemoteException e) {
53            return null;
54        }
55    }
56
57    /**
58     * Internal constructor, to be used by NfcAdapter
59     * @hide
60     */
61    public NdefFormatable(Tag tag) throws RemoteException {
62        super(tag, TagTechnology.NDEF_FORMATABLE);
63    }
64
65    /**
66     * Formats a tag as NDEF, if possible. You may supply a first
67     * NdefMessage to be written on the tag.
68     */
69    public void format(NdefMessage firstMessage) throws IOException, FormatException {
70        checkConnected();
71
72        try {
73            int serviceHandle = mTag.getServiceHandle();
74            INfcTag tagService = mTag.getTagService();
75            int errorCode = tagService.formatNdef(serviceHandle, MifareClassic.KEY_DEFAULT);
76            switch (errorCode) {
77                case ErrorCodes.SUCCESS:
78                    break;
79                case ErrorCodes.ERROR_IO:
80                    throw new IOException();
81                case ErrorCodes.ERROR_INVALID_PARAM:
82                    throw new FormatException();
83                default:
84                    // Should not happen
85                    throw new IOException();
86            }
87            // Now check and see if the format worked
88            if (tagService.isNdef(serviceHandle)) {
89                errorCode = tagService.ndefWrite(serviceHandle, firstMessage);
90                switch (errorCode) {
91                    case ErrorCodes.SUCCESS:
92                        break;
93                    case ErrorCodes.ERROR_IO:
94                        throw new IOException();
95                    case ErrorCodes.ERROR_INVALID_PARAM:
96                        throw new FormatException();
97                    default:
98                        // Should not happen
99                        throw new IOException();
100                }
101            } else {
102                throw new IOException();
103            }
104        } catch (RemoteException e) {
105            Log.e(TAG, "NFC service dead", e);
106        }
107    }
108}
109