1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
|
/*
* Copyright (C) 2010 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 android.nfc;
import android.content.Intent;
import android.net.Uri;
import android.os.Parcel;
import android.os.Parcelable;
import java.nio.BufferUnderflowException;
import java.nio.ByteBuffer;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Locale;
/**
* Represents an immutable NDEF Record.
* <p>
* NDEF (NFC Data Exchange Format) is a light-weight binary format,
* used to encapsulate typed data. It is specified by the NFC Forum,
* for transmission and storage with NFC, however it is transport agnostic.
* <p>
* NDEF defines messages and records. An NDEF Record contains
* typed data, such as MIME-type media, a URI, or a custom
* application payload. An NDEF Message is a container for
* one or more NDEF Records.
* <p>
* This class represents logical (complete) NDEF Records, and can not be
* used to represent chunked (partial) NDEF Records. However
* {@link NdefMessage#NdefMessage(byte[])} can be used to parse a message
* containing chunked records, and will return a message with unchunked
* (complete) records.
* <p>
* A logical NDEF Record always contains a 3-bit TNF (Type Name Field)
* that provides high level typing for the rest of the record. The
* remaining fields are variable length and not always present:
* <ul>
* <li><em>type</em>: detailed typing for the payload</li>
* <li><em>id</em>: identifier meta-data, not commonly used</li>
* <li><em>payload</em>: the actual payload</li>
* </ul>
* <p>
* Helpers such as {@link NdefRecord#createUri}, {@link NdefRecord#createMime}
* and {@link NdefRecord#createExternal} are included to create well-formatted
* NDEF Records with correctly set tnf, type, id and payload fields, please
* use these helpers whenever possible.
* <p>
* Use the constructor {@link #NdefRecord(short, byte[], byte[], byte[])}
* if you know what you are doing and what to set the fields individually.
* Only basic validation is performed with this constructor, so it is possible
* to create records that do not confirm to the strict NFC Forum
* specifications.
* <p>
* The binary representation of an NDEF Record includes additional flags to
* indicate location with an NDEF message, provide support for chunking of
* NDEF records, and to pack optional fields. This class does not expose
* those details. To write an NDEF Record as binary you must first put it
* into an {@link NdefMessage}, then call {@link NdefMessage#toByteArray()}.
* <p class="note">
* {@link NdefMessage} and {@link NdefRecord} implementations are
* always available, even on Android devices that do not have NFC hardware.
* <p class="note">
* {@link NdefRecord}s are intended to be immutable (and thread-safe),
* however they may contain mutable fields. So take care not to modify
* mutable fields passed into constructors, or modify mutable fields
* obtained by getter methods, unless such modification is explicitly
* marked as safe.
*
* @see NfcAdapter#ACTION_NDEF_DISCOVERED
* @see NdefMessage
*/
public final class NdefRecord implements Parcelable {
/**
* Indicates the record is empty.<p>
* Type, id and payload fields are empty in a {@literal TNF_EMPTY} record.
*/
public static final short TNF_EMPTY = 0x00;
/**
* Indicates the type field contains a well-known RTD type name.<p>
* Use this tnf with RTD types such as {@link #RTD_TEXT}, {@link #RTD_URI}.
* <p>
* The RTD type name format is specified in NFCForum-TS-RTD_1.0.
*
* @see #RTD_URI
* @see #RTD_TEXT
* @see #RTD_SMART_POSTER
* @see #createUri
*/
public static final short TNF_WELL_KNOWN = 0x01;
/**
* Indicates the type field contains a media-type BNF
* construct, defined by RFC 2046.<p>
* Use this with MIME type names such as {@literal "image/jpeg"}, or
* using the helper {@link #createMime}.
*
* @see #createMime
*/
public static final short TNF_MIME_MEDIA = 0x02;
/**
* Indicates the type field contains an absolute-URI
* BNF construct defined by RFC 3986.<p>
* When creating new records prefer {@link #createUri},
* since it offers more compact URI encoding
* ({@literal #RTD_URI} allows compression of common URI prefixes).
*
* @see #createUri
*/
public static final short TNF_ABSOLUTE_URI = 0x03;
/**
* Indicates the type field contains an external type name.<p>
* Used to encode custom payloads. When creating new records
* use the helper {@link #createExternal}.<p>
* The external-type RTD format is specified in NFCForum-TS-RTD_1.0.<p>
* <p>
* Note this TNF should not be used with RTD_TEXT or RTD_URI constants.
* Those are well known RTD constants, not external RTD constants.
*
* @see #createExternal
*/
public static final short TNF_EXTERNAL_TYPE = 0x04;
/**
* Indicates the payload type is unknown.<p>
* NFC Forum explains this should be treated similarly to the
* "application/octet-stream" MIME type. The payload
* type is not explicitly encoded within the record.
* <p>
* The type field is empty in an {@literal TNF_UNKNOWN} record.
*/
public static final short TNF_UNKNOWN = 0x05;
/**
* Indicates the payload is an intermediate or final chunk of a chunked
* NDEF Record.<p>
* {@literal TNF_UNCHANGED} can not be used with this class
* since all {@link NdefRecord}s are already unchunked, however they
* may appear in the binary format.
*/
public static final short TNF_UNCHANGED = 0x06;
/**
* Reserved TNF type.
* <p>
* The NFC Forum NDEF Specification v1.0 suggests for NDEF parsers to treat this
* value like TNF_UNKNOWN.
* @hide
*/
public static final short TNF_RESERVED = 0x07;
/**
* RTD Text type. For use with {@literal TNF_WELL_KNOWN}.
* @see #TNF_WELL_KNOWN
*/
public static final byte[] RTD_TEXT = {0x54}; // "T"
/**
* RTD URI type. For use with {@literal TNF_WELL_KNOWN}.
* @see #TNF_WELL_KNOWN
*/
public static final byte[] RTD_URI = {0x55}; // "U"
/**
* RTD Smart Poster type. For use with {@literal TNF_WELL_KNOWN}.
* @see #TNF_WELL_KNOWN
*/
public static final byte[] RTD_SMART_POSTER = {0x53, 0x70}; // "Sp"
/**
* RTD Alternative Carrier type. For use with {@literal TNF_WELL_KNOWN}.
* @see #TNF_WELL_KNOWN
*/
public static final byte[] RTD_ALTERNATIVE_CARRIER = {0x61, 0x63}; // "ac"
/**
* RTD Handover Carrier type. For use with {@literal TNF_WELL_KNOWN}.
* @see #TNF_WELL_KNOWN
*/
public static final byte[] RTD_HANDOVER_CARRIER = {0x48, 0x63}; // "Hc"
/**
* RTD Handover Request type. For use with {@literal TNF_WELL_KNOWN}.
* @see #TNF_WELL_KNOWN
*/
public static final byte[] RTD_HANDOVER_REQUEST = {0x48, 0x72}; // "Hr"
/**
* RTD Handover Select type. For use with {@literal TNF_WELL_KNOWN}.
* @see #TNF_WELL_KNOWN
*/
public static final byte[] RTD_HANDOVER_SELECT = {0x48, 0x73}; // "Hs"
/**
* RTD Android app type. For use with {@literal TNF_EXTERNAL}.
* <p>
* The payload of a record with type RTD_ANDROID_APP
* should be the package name identifying an application.
* Multiple RTD_ANDROID_APP records may be included
* in a single {@link NdefMessage}.
* <p>
* Use {@link #createApplicationRecord(String)} to create
* RTD_ANDROID_APP records.
* @hide
*/
public static final byte[] RTD_ANDROID_APP = "android.com:pkg".getBytes();
private static final byte FLAG_MB = (byte) 0x80;
private static final byte FLAG_ME = (byte) 0x40;
private static final byte FLAG_CF = (byte) 0x20;
private static final byte FLAG_SR = (byte) 0x10;
private static final byte FLAG_IL = (byte) 0x08;
/**
* NFC Forum "URI Record Type Definition"<p>
* This is a mapping of "URI Identifier Codes" to URI string prefixes,
* per section 3.2.2 of the NFC Forum URI Record Type Definition document.
*/
private static final String[] URI_PREFIX_MAP = new String[] {
"", // 0x00
"http://www.", // 0x01
"https://www.", // 0x02
"http://", // 0x03
"https://", // 0x04
"tel:", // 0x05
"mailto:", // 0x06
"ftp://anonymous:anonymous@", // 0x07
"ftp://ftp.", // 0x08
"ftps://", // 0x09
"sftp://", // 0x0A
"smb://", // 0x0B
"nfs://", // 0x0C
"ftp://", // 0x0D
"dav://", // 0x0E
"news:", // 0x0F
"telnet://", // 0x10
"imap:", // 0x11
"rtsp://", // 0x12
"urn:", // 0x13
"pop:", // 0x14
"sip:", // 0x15
"sips:", // 0x16
"tftp:", // 0x17
"btspp://", // 0x18
"btl2cap://", // 0x19
"btgoep://", // 0x1A
"tcpobex://", // 0x1B
"irdaobex://", // 0x1C
"file://", // 0x1D
"urn:epc:id:", // 0x1E
"urn:epc:tag:", // 0x1F
"urn:epc:pat:", // 0x20
"urn:epc:raw:", // 0x21
"urn:epc:", // 0x22
};
private static final int MAX_PAYLOAD_SIZE = 10 * (1 << 20); // 10 MB payload limit
private static final byte[] EMPTY_BYTE_ARRAY = new byte[0];
private final short mTnf;
private final byte[] mType;
private final byte[] mId;
private final byte[] mPayload;
/**
* Create a new Android Application Record (AAR).
* <p>
* This record indicates to other Android devices the package
* that should be used to handle the entire NDEF message.
* You can embed this record anywhere into your message
* to ensure that the intended package receives the message.
* <p>
* When an Android device dispatches an {@link NdefMessage}
* containing one or more Android application records,
* the applications contained in those records will be the
* preferred target for the {@link NfcAdapter#ACTION_NDEF_DISCOVERED}
* intent, in the order in which they appear in the message.
* This dispatch behavior was first added to Android in
* Ice Cream Sandwich.
* <p>
* If none of the applications have a are installed on the device,
* a Market link will be opened to the first application.
* <p>
* Note that Android application records do not overrule
* applications that have called
* {@link NfcAdapter#enableForegroundDispatch}.
*
* @param packageName Android package name
* @return Android application NDEF record
*/
public static NdefRecord createApplicationRecord(String packageName) {
if (packageName == null) throw new NullPointerException("packageName is null");
if (packageName.length() == 0) throw new IllegalArgumentException("packageName is empty");
return new NdefRecord(TNF_EXTERNAL_TYPE, RTD_ANDROID_APP, null,
packageName.getBytes(StandardCharsets.UTF_8));
}
/**
* Create a new NDEF Record containing a URI.<p>
* Use this method to encode a URI (or URL) into an NDEF Record.<p>
* Uses the well known URI type representation: {@link #TNF_WELL_KNOWN}
* and {@link #RTD_URI}. This is the most efficient encoding
* of a URI into NDEF.<p>
* The uri parameter will be normalized with
* {@link Uri#normalizeScheme} to set the scheme to lower case to
* follow Android best practices for intent filtering.
* However the unchecked exception
* {@link IllegalArgumentException} may be thrown if the uri
* parameter has serious problems, for example if it is empty, so always
* catch this exception if you are passing user-generated data into this
* method.<p>
*
* Reference specification: NFCForum-TS-RTD_URI_1.0
*
* @param uri URI to encode.
* @return an NDEF Record containing the URI
* @throws IllegalArugmentException if the uri is empty or invalid
*/
public static NdefRecord createUri(Uri uri) {
if (uri == null) throw new NullPointerException("uri is null");
uri = uri.normalizeScheme();
String uriString = uri.toString();
if (uriString.length() == 0) throw new IllegalArgumentException("uri is empty");
byte prefix = 0;
for (int i = 1; i < URI_PREFIX_MAP.length; i++) {
if (uriString.startsWith(URI_PREFIX_MAP[i])) {
prefix = (byte) i;
uriString = uriString.substring(URI_PREFIX_MAP[i].length());
break;
}
}
byte[] uriBytes = uriString.getBytes(StandardCharsets.UTF_8);
byte[] recordBytes = new byte[uriBytes.length + 1];
recordBytes[0] = prefix;
System.arraycopy(uriBytes, 0, recordBytes, 1, uriBytes.length);
return new NdefRecord(TNF_WELL_KNOWN, RTD_URI, null, recordBytes);
}
/**
* Create a new NDEF Record containing a URI.<p>
* Use this method to encode a URI (or URL) into an NDEF Record.<p>
* Uses the well known URI type representation: {@link #TNF_WELL_KNOWN}
* and {@link #RTD_URI}. This is the most efficient encoding
* of a URI into NDEF.<p>
* The uriString parameter will be normalized with
* {@link Uri#normalizeScheme} to set the scheme to lower case to
* follow Android best practices for intent filtering.
* However the unchecked exception
* {@link IllegalArgumentException} may be thrown if the uriString
* parameter has serious problems, for example if it is empty, so always
* catch this exception if you are passing user-generated data into this
* method.<p>
*
* Reference specification: NFCForum-TS-RTD_URI_1.0
*
* @param uriString string URI to encode.
* @return an NDEF Record containing the URI
* @throws IllegalArugmentException if the uriString is empty or invalid
*/
public static NdefRecord createUri(String uriString) {
return createUri(Uri.parse(uriString));
}
/**
* Create a new NDEF Record containing MIME data.<p>
* Use this method to encode MIME-typed data into an NDEF Record,
* such as "text/plain", or "image/jpeg".<p>
* The mimeType parameter will be normalized with
* {@link Intent#normalizeMimeType} to follow Android best
* practices for intent filtering, for example to force lower-case.
* However the unchecked exception
* {@link IllegalArgumentException} may be thrown
* if the mimeType parameter has serious problems,
* for example if it is empty, so always catch this
* exception if you are passing user-generated data into this method.
* <p>
* For efficiency, This method might not make an internal copy of the
* mimeData byte array, so take care not
* to modify the mimeData byte array while still using the returned
* NdefRecord.
*
* @param mimeType a valid MIME type
* @param mimeData MIME data as bytes
* @return an NDEF Record containing the MIME-typed data
* @throws IllegalArugmentException if the mimeType is empty or invalid
*
*/
public static NdefRecord createMime(String mimeType, byte[] mimeData) {
if (mimeType == null) throw new NullPointerException("mimeType is null");
// We only do basic MIME type validation: trying to follow the
// RFCs strictly only ends in tears, since there are lots of MIME
// types in common use that are not strictly valid as per RFC rules
mimeType = Intent.normalizeMimeType(mimeType);
if (mimeType.length() == 0) throw new IllegalArgumentException("mimeType is empty");
int slashIndex = mimeType.indexOf('/');
if (slashIndex == 0) throw new IllegalArgumentException("mimeType must have major type");
if (slashIndex == mimeType.length() - 1) {
throw new IllegalArgumentException("mimeType must have minor type");
}
// missing '/' is allowed
// MIME RFCs suggest ASCII encoding for content-type
byte[] typeBytes = mimeType.getBytes(StandardCharsets.US_ASCII);
return new NdefRecord(TNF_MIME_MEDIA, typeBytes, null, mimeData);
}
/**
* Create a new NDEF Record containing external (application-specific) data.<p>
* Use this method to encode application specific data into an NDEF Record.
* The data is typed by a domain name (usually your Android package name) and
* a domain-specific type. This data is packaged into a "NFC Forum External
* Type" NDEF Record.<p>
* NFC Forum requires that the domain and type used in an external record
* are treated as case insensitive, however Android intent filtering is
* always case sensitive. So this method will force the domain and type to
* lower-case before creating the NDEF Record.<p>
* The unchecked exception {@link IllegalArgumentException} will be thrown
* if the domain and type have serious problems, for example if either field
* is empty, so always catch this
* exception if you are passing user-generated data into this method.<p>
* There are no such restrictions on the payload data.<p>
* For efficiency, This method might not make an internal copy of the
* data byte array, so take care not
* to modify the data byte array while still using the returned
* NdefRecord.
*
* Reference specification: NFCForum-TS-RTD_1.0
* @param domain domain-name of issuing organization
* @param type domain-specific type of data
* @param data payload as bytes
* @throws IllegalArugmentException if either domain or type are empty or invalid
*/
public static NdefRecord createExternal(String domain, String type, byte[] data) {
if (domain == null) throw new NullPointerException("domain is null");
if (type == null) throw new NullPointerException("type is null");
domain = domain.trim().toLowerCase(Locale.ROOT);
type = type.trim().toLowerCase(Locale.ROOT);
if (domain.length() == 0) throw new IllegalArgumentException("domain is empty");
if (type.length() == 0) throw new IllegalArgumentException("type is empty");
byte[] byteDomain = domain.getBytes(StandardCharsets.UTF_8);
byte[] byteType = type.getBytes(StandardCharsets.UTF_8);
byte[] b = new byte[byteDomain.length + 1 + byteType.length];
System.arraycopy(byteDomain, 0, b, 0, byteDomain.length);
b[byteDomain.length] = ':';
System.arraycopy(byteType, 0, b, byteDomain.length + 1, byteType.length);
return new NdefRecord(TNF_EXTERNAL_TYPE, b, null, data);
}
/**
* Construct an NDEF Record from its component fields.<p>
* Recommend to use helpers such as {#createUri} or
* {{@link #createExternal} where possible, since they perform
* stricter validation that the record is correctly formatted
* as per NDEF specifications. However if you know what you are
* doing then this constructor offers the most flexibility.<p>
* An {@link NdefRecord} represents a logical (complete)
* record, and cannot represent NDEF Record chunks.<p>
* Basic validation of the tnf, type, id and payload is performed
* as per the following rules:
* <ul>
* <li>The tnf paramter must be a 3-bit value.</li>
* <li>Records with a tnf of {@link #TNF_EMPTY} cannot have a type,
* id or payload.</li>
* <li>Records with a tnf of {@link #TNF_UNKNOWN} or {@literal 0x07}
* cannot have a type.</li>
* <li>Records with a tnf of {@link #TNF_UNCHANGED} are not allowed
* since this class only represents complete (unchunked) records.</li>
* </ul>
* This minimal validation is specified by
* NFCForum-TS-NDEF_1.0 section 3.2.6 (Type Name Format).<p>
* If any of the above validation
* steps fail then {@link IllegalArgumentException} is thrown.<p>
* Deep inspection of the type, id and payload fields is not
* performed, so it is possible to create NDEF Records
* that conform to section 3.2.6
* but fail other more strict NDEF specification requirements. For
* example, the payload may be invalid given the tnf and type.
* <p>
* To omit a type, id or payload field, set the parameter to an
* empty byte array or null.
*
* @param tnf a 3-bit TNF constant
* @param type byte array, containing zero to 255 bytes, or null
* @param id byte array, containing zero to 255 bytes, or null
* @param payload byte array, containing zero to (2 ** 32 - 1) bytes,
* or null
* @throws IllegalArugmentException if a valid record cannot be created
*/
public NdefRecord(short tnf, byte[] type, byte[] id, byte[] payload) {
/* convert nulls */
if (type == null) type = EMPTY_BYTE_ARRAY;
if (id == null) id = EMPTY_BYTE_ARRAY;
if (payload == null) payload = EMPTY_BYTE_ARRAY;
String message = validateTnf(tnf, type, id, payload);
if (message != null) {
throw new IllegalArgumentException(message);
}
mTnf = tnf;
mType = type;
mId = id;
mPayload = payload;
}
/**
* Construct an NDEF Record from raw bytes.<p>
* This method is deprecated, use {@link NdefMessage#NdefMessage(byte[])}
* instead. This is because it does not make sense to parse a record:
* the NDEF binary format is only defined for a message, and the
* record flags MB and ME do not make sense outside of the context of
* an entire message.<p>
* This implementation will attempt to parse a single record by ignoring
* the MB and ME flags, and otherwise following the rules of
* {@link NdefMessage#NdefMessage(byte[])}.<p>
*
* @param data raw bytes to parse
* @throws FormatException if the data cannot be parsed into a valid record
* @deprecated use {@link NdefMessage#NdefMessage(byte[])} instead.
*/
@Deprecated
public NdefRecord(byte[] data) throws FormatException {
ByteBuffer buffer = ByteBuffer.wrap(data);
NdefRecord[] rs = parse(buffer, true);
if (buffer.remaining() > 0) {
throw new FormatException("data too long");
}
mTnf = rs[0].mTnf;
mType = rs[0].mType;
mId = rs[0].mId;
mPayload = rs[0].mPayload;
}
/**
* Returns the 3-bit TNF.
* <p>
* TNF is the top-level type.
*/
public short getTnf() {
return mTnf;
}
/**
* Returns the variable length Type field.
* <p>
* This should be used in conjunction with the TNF field to determine the
* payload format.
* <p>
* Returns an empty byte array if this record
* does not have a type field.
*/
public byte[] getType() {
return mType.clone();
}
/**
* Returns the variable length ID.
* <p>
* Returns an empty byte array if this record
* does not have an id field.
*/
public byte[] getId() {
return mId.clone();
}
/**
* Returns the variable length payload.
* <p>
* Returns an empty byte array if this record
* does not have a payload field.
*/
public byte[] getPayload() {
return mPayload.clone();
}
/**
* Return this NDEF Record as a byte array.<p>
* This method is deprecated, use {@link NdefMessage#toByteArray}
* instead. This is because the NDEF binary format is not defined for
* a record outside of the context of a message: the MB and ME flags
* cannot be set without knowing the location inside a message.<p>
* This implementation will attempt to serialize a single record by
* always setting the MB and ME flags (in other words, assume this
* is a single-record NDEF Message).<p>
*
* @deprecated use {@link NdefMessage#toByteArray()} instead
*/
@Deprecated
public byte[] toByteArray() {
ByteBuffer buffer = ByteBuffer.allocate(getByteLength());
writeToByteBuffer(buffer, true, true);
return buffer.array();
}
/**
* Map this record to a MIME type, or return null if it cannot be mapped.<p>
* Currently this method considers all {@link #TNF_MIME_MEDIA} records to
* be MIME records, as well as some {@link #TNF_WELL_KNOWN} records such as
* {@link #RTD_TEXT}. If this is a MIME record then the MIME type as string
* is returned, otherwise null is returned.<p>
* This method does not perform validation that the MIME type is
* actually valid. It always attempts to
* return a string containing the type if this is a MIME record.<p>
* The returned MIME type will by normalized to lower-case using
* {@link Intent#normalizeMimeType}.<p>
* The MIME payload can be obtained using {@link #getPayload}.
*
* @return MIME type as a string, or null if this is not a MIME record
*/
public String toMimeType() {
switch (mTnf) {
case NdefRecord.TNF_WELL_KNOWN:
if (Arrays.equals(mType, NdefRecord.RTD_TEXT)) {
return "text/plain";
}
break;
case NdefRecord.TNF_MIME_MEDIA:
String mimeType = new String(mType, StandardCharsets.US_ASCII);
return Intent.normalizeMimeType(mimeType);
}
return null;
}
/**
* Map this record to a URI, or return null if it cannot be mapped.<p>
* Currently this method considers the following to be URI records:
* <ul>
* <li>{@link #TNF_ABSOLUTE_URI} records.</li>
* <li>{@link #TNF_WELL_KNOWN} with a type of {@link #RTD_URI}.</li>
* <li>{@link #TNF_WELL_KNOWN} with a type of {@link #RTD_SMART_POSTER}
* and containing a URI record in the NDEF message nested in the payload.
* </li>
* <li>{@link #TNF_EXTERNAL_TYPE} records.</li>
* </ul>
* If this is not a URI record by the above rules, then null is returned.<p>
* This method does not perform validation that the URI is
* actually valid: it always attempts to create and return a URI if
* this record appears to be a URI record by the above rules.<p>
* The returned URI will be normalized to have a lower case scheme
* using {@link Uri#normalizeScheme}.<p>
*
* @return URI, or null if this is not a URI record
*/
public Uri toUri() {
return toUri(false);
}
private Uri toUri(boolean inSmartPoster) {
switch (mTnf) {
case TNF_WELL_KNOWN:
if (Arrays.equals(mType, RTD_SMART_POSTER) && !inSmartPoster) {
try {
// check payload for a nested NDEF Message containing a URI
NdefMessage nestedMessage = new NdefMessage(mPayload);
for (NdefRecord nestedRecord : nestedMessage.getRecords()) {
Uri uri = nestedRecord.toUri(true);
if (uri != null) {
return uri;
}
}
} catch (FormatException e) { }
} else if (Arrays.equals(mType, RTD_URI)) {
Uri wktUri = parseWktUri();
return (wktUri != null ? wktUri.normalizeScheme() : null);
}
break;
case TNF_ABSOLUTE_URI:
Uri uri = Uri.parse(new String(mType, StandardCharsets.UTF_8));
return uri.normalizeScheme();
case TNF_EXTERNAL_TYPE:
if (inSmartPoster) {
break;
}
return Uri.parse("vnd.android.nfc://ext/" + new String(mType, StandardCharsets.US_ASCII));
}
return null;
}
/**
* Return complete URI of {@link #TNF_WELL_KNOWN}, {@link #RTD_URI} records.
* @return complete URI, or null if invalid
*/
private Uri parseWktUri() {
if (mPayload.length < 2) {
return null;
}
// payload[0] contains the URI Identifier Code, as per
// NFC Forum "URI Record Type Definition" section 3.2.2.
int prefixIndex = (mPayload[0] & (byte)0xFF);
if (prefixIndex < 0 || prefixIndex >= URI_PREFIX_MAP.length) {
return null;
}
String prefix = URI_PREFIX_MAP[prefixIndex];
String suffix = new String(Arrays.copyOfRange(mPayload, 1, mPayload.length),
StandardCharsets.UTF_8);
return Uri.parse(prefix + suffix);
}
/**
* Main record parsing method.<p>
* Expects NdefMessage to begin immediately, allows trailing data.<p>
* Currently has strict validation of all fields as per NDEF 1.0
* specification section 2.5. We will attempt to keep this as strict as
* possible to encourage well-formatted NDEF.<p>
* Always returns 1 or more NdefRecord's, or throws FormatException.
*
* @param buffer ByteBuffer to read from
* @param ignoreMbMe ignore MB and ME flags, and read only 1 complete record
* @return one or more records
* @throws FormatException on any parsing error
*/
static NdefRecord[] parse(ByteBuffer buffer, boolean ignoreMbMe) throws FormatException {
List<NdefRecord> records = new ArrayList<NdefRecord>();
try {
byte[] type = null;
byte[] id = null;
byte[] payload = null;
ArrayList<byte[]> chunks = new ArrayList<byte[]>();
boolean inChunk = false;
short chunkTnf = -1;
boolean me = false;
while (!me) {
byte flag = buffer.get();
boolean mb = (flag & NdefRecord.FLAG_MB) != 0;
me = (flag & NdefRecord.FLAG_ME) != 0;
boolean cf = (flag & NdefRecord.FLAG_CF) != 0;
boolean sr = (flag & NdefRecord.FLAG_SR) != 0;
boolean il = (flag & NdefRecord.FLAG_IL) != 0;
short tnf = (short)(flag & 0x07);
if (!mb && records.size() == 0 && !inChunk && !ignoreMbMe) {
throw new FormatException("expected MB flag");
} else if (mb && records.size() != 0 && !ignoreMbMe) {
throw new FormatException("unexpected MB flag");
} else if (inChunk && il) {
throw new FormatException("unexpected IL flag in non-leading chunk");
} else if (cf && me) {
throw new FormatException("unexpected ME flag in non-trailing chunk");
} else if (inChunk && tnf != NdefRecord.TNF_UNCHANGED) {
throw new FormatException("expected TNF_UNCHANGED in non-leading chunk");
} else if (!inChunk && tnf == NdefRecord.TNF_UNCHANGED) {
throw new FormatException("" +
"unexpected TNF_UNCHANGED in first chunk or unchunked record");
}
int typeLength = buffer.get() & 0xFF;
long payloadLength = sr ? (buffer.get() & 0xFF) : (buffer.getInt() & 0xFFFFFFFFL);
int idLength = il ? (buffer.get() & 0xFF) : 0;
if (inChunk && typeLength != 0) {
throw new FormatException("expected zero-length type in non-leading chunk");
}
if (!inChunk) {
type = (typeLength > 0 ? new byte[typeLength] : EMPTY_BYTE_ARRAY);
id = (idLength > 0 ? new byte[idLength] : EMPTY_BYTE_ARRAY);
buffer.get(type);
buffer.get(id);
}
ensureSanePayloadSize(payloadLength);
payload = (payloadLength > 0 ? new byte[(int)payloadLength] : EMPTY_BYTE_ARRAY);
buffer.get(payload);
if (cf && !inChunk) {
// first chunk
chunks.clear();
chunkTnf = tnf;
}
if (cf || inChunk) {
// any chunk
chunks.add(payload);
}
if (!cf && inChunk) {
// last chunk, flatten the payload
payloadLength = 0;
for (byte[] p : chunks) {
payloadLength += p.length;
}
ensureSanePayloadSize(payloadLength);
payload = new byte[(int)payloadLength];
int i = 0;
for (byte[] p : chunks) {
System.arraycopy(p, 0, payload, i, p.length);
i += p.length;
}
tnf = chunkTnf;
}
if (cf) {
// more chunks to come
inChunk = true;
continue;
} else {
inChunk = false;
}
String error = validateTnf(tnf, type, id, payload);
if (error != null) {
throw new FormatException(error);
}
records.add(new NdefRecord(tnf, type, id, payload));
if (ignoreMbMe) { // for parsing a single NdefRecord
break;
}
}
} catch (BufferUnderflowException e) {
throw new FormatException("expected more data", e);
}
return records.toArray(new NdefRecord[records.size()]);
}
private static void ensureSanePayloadSize(long size) throws FormatException {
if (size > MAX_PAYLOAD_SIZE) {
throw new FormatException(
"payload above max limit: " + size + " > " + MAX_PAYLOAD_SIZE);
}
}
/**
* Perform simple validation that the tnf is valid.<p>
* Validates the requirements of NFCForum-TS-NDEF_1.0 section
* 3.2.6 (Type Name Format). This just validates that the tnf
* is valid, and that the relevant type, id and payload
* fields are present (or empty) for this tnf. It does not
* perform any deep inspection of the type, id and payload fields.<p>
* Also does not allow TNF_UNCHANGED since this class is only used
* to present logical (unchunked) records.
*
* @return null if valid, or a string error if invalid.
*/
static String validateTnf(short tnf, byte[] type, byte[] id, byte[] payload) {
switch (tnf) {
case TNF_EMPTY:
if (type.length != 0 || id.length != 0 || payload.length != 0) {
return "unexpected data in TNF_EMPTY record";
}
return null;
case TNF_WELL_KNOWN:
case TNF_MIME_MEDIA:
case TNF_ABSOLUTE_URI:
case TNF_EXTERNAL_TYPE:
return null;
case TNF_UNKNOWN:
case TNF_RESERVED:
if (type.length != 0) {
return "unexpected type field in TNF_UNKNOWN or TNF_RESERVEd record";
}
return null;
case TNF_UNCHANGED:
return "unexpected TNF_UNCHANGED in first chunk or logical record";
default:
return String.format("unexpected tnf value: 0x%02x", tnf);
}
}
/**
* Serialize record for network transmission.<p>
* Uses specified MB and ME flags.<p>
* Does not chunk records.
*/
void writeToByteBuffer(ByteBuffer buffer, boolean mb, boolean me) {
boolean sr = mPayload.length < 256;
boolean il = mId.length > 0;
byte flags = (byte)((mb ? FLAG_MB : 0) | (me ? FLAG_ME : 0) |
(sr ? FLAG_SR : 0) | (il ? FLAG_IL : 0) | mTnf);
buffer.put(flags);
buffer.put((byte)mType.length);
if (sr) {
buffer.put((byte)mPayload.length);
} else {
buffer.putInt(mPayload.length);
}
if (il) {
buffer.put((byte)mId.length);
}
buffer.put(mType);
buffer.put(mId);
buffer.put(mPayload);
}
/**
* Get byte length of serialized record.
*/
int getByteLength() {
int length = 3 + mType.length + mId.length + mPayload.length;
boolean sr = mPayload.length < 256;
boolean il = mId.length > 0;
if (!sr) length += 3;
if (il) length += 1;
return length;
}
@Override
public int describeContents() {
return 0;
}
@Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeInt(mTnf);
dest.writeInt(mType.length);
dest.writeByteArray(mType);
dest.writeInt(mId.length);
dest.writeByteArray(mId);
dest.writeInt(mPayload.length);
dest.writeByteArray(mPayload);
}
public static final Parcelable.Creator<NdefRecord> CREATOR =
new Parcelable.Creator<NdefRecord>() {
@Override
public NdefRecord createFromParcel(Parcel in) {
short tnf = (short)in.readInt();
int typeLength = in.readInt();
byte[] type = new byte[typeLength];
in.readByteArray(type);
int idLength = in.readInt();
byte[] id = new byte[idLength];
in.readByteArray(id);
int payloadLength = in.readInt();
byte[] payload = new byte[payloadLength];
in.readByteArray(payload);
return new NdefRecord(tnf, type, id, payload);
}
@Override
public NdefRecord[] newArray(int size) {
return new NdefRecord[size];
}
};
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + Arrays.hashCode(mId);
result = prime * result + Arrays.hashCode(mPayload);
result = prime * result + mTnf;
result = prime * result + Arrays.hashCode(mType);
return result;
}
/**
* Returns true if the specified NDEF Record contains
* identical tnf, type, id and payload fields.
*/
@Override
public boolean equals(Object obj) {
if (this == obj) return true;
if (obj == null) return false;
if (getClass() != obj.getClass()) return false;
NdefRecord other = (NdefRecord) obj;
if (!Arrays.equals(mId, other.mId)) return false;
if (!Arrays.equals(mPayload, other.mPayload)) return false;
if (mTnf != other.mTnf) return false;
return Arrays.equals(mType, other.mType);
}
@Override
public String toString() {
StringBuilder b = new StringBuilder(String.format("NdefRecord tnf=%X", mTnf));
if (mType.length > 0) b.append(" type=").append(bytesToString(mType));
if (mId.length > 0) b.append(" id=").append(bytesToString(mId));
if (mPayload.length > 0) b.append(" payload=").append(bytesToString(mPayload));
return b.toString();
}
private static StringBuilder bytesToString(byte[] bs) {
StringBuilder s = new StringBuilder();
for (byte b : bs) {
s.append(String.format("%02X", b));
}
return s;
}
}
|