summaryrefslogtreecommitdiffstats
path: root/core/java/android/app/DownloadManager.java
blob: 12c851b38fe55b4a74f64085a9892210a9d3df2b (plain)
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
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
/*
 * 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.app;

import android.annotation.SdkConstant;
import android.annotation.SdkConstant.SdkConstantType;
import android.content.ContentResolver;
import android.content.ContentUris;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.CursorWrapper;
import android.net.ConnectivityManager;
import android.net.NetworkPolicyManager;
import android.net.Uri;
import android.os.Environment;
import android.os.ParcelFileDescriptor;
import android.provider.Downloads;
import android.provider.Settings;
import android.provider.Settings.SettingNotFoundException;
import android.text.TextUtils;
import android.util.Pair;

import java.io.File;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.List;

/**
 * The download manager is a system service that handles long-running HTTP downloads. Clients may
 * request that a URI be downloaded to a particular destination file. The download manager will
 * conduct the download in the background, taking care of HTTP interactions and retrying downloads
 * after failures or across connectivity changes and system reboots.
 *
 * Instances of this class should be obtained through
 * {@link android.content.Context#getSystemService(String)} by passing
 * {@link android.content.Context#DOWNLOAD_SERVICE}.
 *
 * Apps that request downloads through this API should register a broadcast receiver for
 * {@link #ACTION_NOTIFICATION_CLICKED} to appropriately handle when the user clicks on a running
 * download in a notification or from the downloads UI.
 *
 * Note that the application must have the {@link android.Manifest.permission#INTERNET}
 * permission to use this class.
 */
public class DownloadManager {

    /**
     * An identifier for a particular download, unique across the system.  Clients use this ID to
     * make subsequent calls related to the download.
     */
    public final static String COLUMN_ID = Downloads.Impl._ID;

    /**
     * The client-supplied title for this download.  This will be displayed in system notifications.
     * Defaults to the empty string.
     */
    public final static String COLUMN_TITLE = Downloads.Impl.COLUMN_TITLE;

    /**
     * The client-supplied description of this download.  This will be displayed in system
     * notifications.  Defaults to the empty string.
     */
    public final static String COLUMN_DESCRIPTION = Downloads.Impl.COLUMN_DESCRIPTION;

    /**
     * URI to be downloaded.
     */
    public final static String COLUMN_URI = Downloads.Impl.COLUMN_URI;

    /**
     * Internet Media Type of the downloaded file.  If no value is provided upon creation, this will
     * initially be null and will be filled in based on the server's response once the download has
     * started.
     *
     * @see <a href="http://www.ietf.org/rfc/rfc1590.txt">RFC 1590, defining Media Types</a>
     */
    public final static String COLUMN_MEDIA_TYPE = "media_type";

    /**
     * Total size of the download in bytes.  This will initially be -1 and will be filled in once
     * the download starts.
     */
    public final static String COLUMN_TOTAL_SIZE_BYTES = "total_size";

    /**
     * Uri where downloaded file will be stored.  If a destination is supplied by client, that URI
     * will be used here.  Otherwise, the value will initially be null and will be filled in with a
     * generated URI once the download has started.
     */
    public final static String COLUMN_LOCAL_URI = "local_uri";

    /**
     * The pathname of the file where the download is stored.
     */
    public final static String COLUMN_LOCAL_FILENAME = "local_filename";

    /**
     * Current status of the download, as one of the STATUS_* constants.
     */
    public final static String COLUMN_STATUS = Downloads.Impl.COLUMN_STATUS;

    /**
     * Provides more detail on the status of the download.  Its meaning depends on the value of
     * {@link #COLUMN_STATUS}.
     *
     * When {@link #COLUMN_STATUS} is {@link #STATUS_FAILED}, this indicates the type of error that
     * occurred.  If an HTTP error occurred, this will hold the HTTP status code as defined in RFC
     * 2616.  Otherwise, it will hold one of the ERROR_* constants.
     *
     * When {@link #COLUMN_STATUS} is {@link #STATUS_PAUSED}, this indicates why the download is
     * paused.  It will hold one of the PAUSED_* constants.
     *
     * If {@link #COLUMN_STATUS} is neither {@link #STATUS_FAILED} nor {@link #STATUS_PAUSED}, this
     * column's value is undefined.
     *
     * @see <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec6.html#sec6.1.1">RFC 2616
     * status codes</a>
     */
    public final static String COLUMN_REASON = "reason";

    /**
     * Number of bytes download so far.
     */
    public final static String COLUMN_BYTES_DOWNLOADED_SO_FAR = "bytes_so_far";

    /**
     * Timestamp when the download was last modified, in {@link System#currentTimeMillis
     * System.currentTimeMillis()} (wall clock time in UTC).
     */
    public final static String COLUMN_LAST_MODIFIED_TIMESTAMP = "last_modified_timestamp";

    /**
     * The URI to the corresponding entry in MediaProvider for this downloaded entry. It is
     * used to delete the entries from MediaProvider database when it is deleted from the
     * downloaded list.
     */
    public static final String COLUMN_MEDIAPROVIDER_URI = Downloads.Impl.COLUMN_MEDIAPROVIDER_URI;

    /**
     * @hide
     */
    public final static String COLUMN_ALLOW_WRITE = Downloads.Impl.COLUMN_ALLOW_WRITE;

    /**
     * Value of {@link #COLUMN_STATUS} when the download is waiting to start.
     */
    public final static int STATUS_PENDING = 1 << 0;

    /**
     * Value of {@link #COLUMN_STATUS} when the download is currently running.
     */
    public final static int STATUS_RUNNING = 1 << 1;

    /**
     * Value of {@link #COLUMN_STATUS} when the download is waiting to retry or resume.
     */
    public final static int STATUS_PAUSED = 1 << 2;

    /**
     * Value of {@link #COLUMN_STATUS} when the download has successfully completed.
     */
    public final static int STATUS_SUCCESSFUL = 1 << 3;

    /**
     * Value of {@link #COLUMN_STATUS} when the download has failed (and will not be retried).
     */
    public final static int STATUS_FAILED = 1 << 4;

    /**
     * Value of COLUMN_ERROR_CODE when the download has completed with an error that doesn't fit
     * under any other error code.
     */
    public final static int ERROR_UNKNOWN = 1000;

    /**
     * Value of {@link #COLUMN_REASON} when a storage issue arises which doesn't fit under any
     * other error code. Use the more specific {@link #ERROR_INSUFFICIENT_SPACE} and
     * {@link #ERROR_DEVICE_NOT_FOUND} when appropriate.
     */
    public final static int ERROR_FILE_ERROR = 1001;

    /**
     * Value of {@link #COLUMN_REASON} when an HTTP code was received that download manager
     * can't handle.
     */
    public final static int ERROR_UNHANDLED_HTTP_CODE = 1002;

    /**
     * Value of {@link #COLUMN_REASON} when an error receiving or processing data occurred at
     * the HTTP level.
     */
    public final static int ERROR_HTTP_DATA_ERROR = 1004;

    /**
     * Value of {@link #COLUMN_REASON} when there were too many redirects.
     */
    public final static int ERROR_TOO_MANY_REDIRECTS = 1005;

    /**
     * Value of {@link #COLUMN_REASON} when there was insufficient storage space. Typically,
     * this is because the SD card is full.
     */
    public final static int ERROR_INSUFFICIENT_SPACE = 1006;

    /**
     * Value of {@link #COLUMN_REASON} when no external storage device was found. Typically,
     * this is because the SD card is not mounted.
     */
    public final static int ERROR_DEVICE_NOT_FOUND = 1007;

    /**
     * Value of {@link #COLUMN_REASON} when some possibly transient error occurred but we can't
     * resume the download.
     */
    public final static int ERROR_CANNOT_RESUME = 1008;

    /**
     * Value of {@link #COLUMN_REASON} when the requested destination file already exists (the
     * download manager will not overwrite an existing file).
     */
    public final static int ERROR_FILE_ALREADY_EXISTS = 1009;

    /**
     * Value of {@link #COLUMN_REASON} when the download has failed because of
     * {@link NetworkPolicyManager} controls on the requesting application.
     *
     * @hide
     */
    public final static int ERROR_BLOCKED = 1010;

    /**
     * Value of {@link #COLUMN_REASON} when the download is paused because some network error
     * occurred and the download manager is waiting before retrying the request.
     */
    public final static int PAUSED_WAITING_TO_RETRY = 1;

    /**
     * Value of {@link #COLUMN_REASON} when the download is waiting for network connectivity to
     * proceed.
     */
    public final static int PAUSED_WAITING_FOR_NETWORK = 2;

    /**
     * Value of {@link #COLUMN_REASON} when the download exceeds a size limit for downloads over
     * the mobile network and the download manager is waiting for a Wi-Fi connection to proceed.
     */
    public final static int PAUSED_QUEUED_FOR_WIFI = 3;

    /**
     * Value of {@link #COLUMN_REASON} when the download is paused for some other reason.
     */
    public final static int PAUSED_UNKNOWN = 4;

    /**
     * Broadcast intent action sent by the download manager when a download completes.
     */
    @SdkConstant(SdkConstantType.BROADCAST_INTENT_ACTION)
    public final static String ACTION_DOWNLOAD_COMPLETE = "android.intent.action.DOWNLOAD_COMPLETE";

    /**
     * Broadcast intent action sent by the download manager when the user clicks on a running
     * download, either from a system notification or from the downloads UI.
     */
    @SdkConstant(SdkConstantType.BROADCAST_INTENT_ACTION)
    public final static String ACTION_NOTIFICATION_CLICKED =
            "android.intent.action.DOWNLOAD_NOTIFICATION_CLICKED";

    /**
     * Intent action to launch an activity to display all downloads.
     */
    @SdkConstant(SdkConstantType.ACTIVITY_INTENT_ACTION)
    public final static String ACTION_VIEW_DOWNLOADS = "android.intent.action.VIEW_DOWNLOADS";

    /**
     * Intent extra included with {@link #ACTION_VIEW_DOWNLOADS} to start DownloadApp in
     * sort-by-size mode.
     */
    public final static String INTENT_EXTRAS_SORT_BY_SIZE =
            "android.app.DownloadManager.extra_sortBySize";

    /**
     * Intent extra included with {@link #ACTION_DOWNLOAD_COMPLETE} intents, indicating the ID (as a
     * long) of the download that just completed.
     */
    public static final String EXTRA_DOWNLOAD_ID = "extra_download_id";

    /**
     * When clicks on multiple notifications are received, the following
     * provides an array of download ids corresponding to the download notification that was
     * clicked. It can be retrieved by the receiver of this
     * Intent using {@link android.content.Intent#getLongArrayExtra(String)}.
     */
    public static final String EXTRA_NOTIFICATION_CLICK_DOWNLOAD_IDS = "extra_click_download_ids";

    /**
     * columns to request from DownloadProvider.
     * @hide
     */
    public static final String[] UNDERLYING_COLUMNS = new String[] {
        Downloads.Impl._ID,
        Downloads.Impl._DATA + " AS " + COLUMN_LOCAL_FILENAME,
        Downloads.Impl.COLUMN_MEDIAPROVIDER_URI,
        Downloads.Impl.COLUMN_DESTINATION,
        Downloads.Impl.COLUMN_TITLE,
        Downloads.Impl.COLUMN_DESCRIPTION,
        Downloads.Impl.COLUMN_URI,
        Downloads.Impl.COLUMN_STATUS,
        Downloads.Impl.COLUMN_FILE_NAME_HINT,
        Downloads.Impl.COLUMN_MIME_TYPE + " AS " + COLUMN_MEDIA_TYPE,
        Downloads.Impl.COLUMN_TOTAL_BYTES + " AS " + COLUMN_TOTAL_SIZE_BYTES,
        Downloads.Impl.COLUMN_LAST_MODIFICATION + " AS " + COLUMN_LAST_MODIFIED_TIMESTAMP,
        Downloads.Impl.COLUMN_CURRENT_BYTES + " AS " + COLUMN_BYTES_DOWNLOADED_SO_FAR,
        Downloads.Impl.COLUMN_ALLOW_WRITE,
        /* add the following 'computed' columns to the cursor.
         * they are not 'returned' by the database, but their inclusion
         * eliminates need to have lot of methods in CursorTranslator
         */
        "'placeholder' AS " + COLUMN_LOCAL_URI,
        "'placeholder' AS " + COLUMN_REASON
    };

    /**
     * This class contains all the information necessary to request a new download. The URI is the
     * only required parameter.
     *
     * Note that the default download destination is a shared volume where the system might delete
     * your file if it needs to reclaim space for system use. If this is a problem, use a location
     * on external storage (see {@link #setDestinationUri(Uri)}.
     */
    public static class Request {
        /**
         * Bit flag for {@link #setAllowedNetworkTypes} corresponding to
         * {@link ConnectivityManager#TYPE_MOBILE}.
         */
        public static final int NETWORK_MOBILE = 1 << 0;

        /**
         * Bit flag for {@link #setAllowedNetworkTypes} corresponding to
         * {@link ConnectivityManager#TYPE_WIFI}.
         */
        public static final int NETWORK_WIFI = 1 << 1;

        /**
         * Bit flag for {@link #setAllowedNetworkTypes} corresponding to
         * {@link ConnectivityManager#TYPE_BLUETOOTH}.
         * @hide
         */
        public static final int NETWORK_BLUETOOTH = 1 << 2;

        private Uri mUri;
        private Uri mDestinationUri;
        private List<Pair<String, String>> mRequestHeaders = new ArrayList<Pair<String, String>>();
        private CharSequence mTitle;
        private CharSequence mDescription;
        private String mMimeType;
        private int mAllowedNetworkTypes = ~0; // default to all network types allowed
        private boolean mRoamingAllowed = true;
        private boolean mMeteredAllowed = true;
        private boolean mIsVisibleInDownloadsUi = true;
        private boolean mScannable = false;
        private boolean mUseSystemCache = false;
        /** if a file is designated as a MediaScanner scannable file, the following value is
         * stored in the database column {@link Downloads.Impl#COLUMN_MEDIA_SCANNED}.
         */
        private static final int SCANNABLE_VALUE_YES = 0;
        // value of 1 is stored in the above column by DownloadProvider after it is scanned by
        // MediaScanner
        /** if a file is designated as a file that should not be scanned by MediaScanner,
         * the following value is stored in the database column
         * {@link Downloads.Impl#COLUMN_MEDIA_SCANNED}.
         */
        private static final int SCANNABLE_VALUE_NO = 2;

        /**
         * This download is visible but only shows in the notifications
         * while it's in progress.
         */
        public static final int VISIBILITY_VISIBLE = 0;

        /**
         * This download is visible and shows in the notifications while
         * in progress and after completion.
         */
        public static final int VISIBILITY_VISIBLE_NOTIFY_COMPLETED = 1;

        /**
         * This download doesn't show in the UI or in the notifications.
         */
        public static final int VISIBILITY_HIDDEN = 2;

        /**
         * This download shows in the notifications after completion ONLY.
         * It is usuable only with
         * {@link DownloadManager#addCompletedDownload(String, String,
         * boolean, String, String, long, boolean)}.
         */
        public static final int VISIBILITY_VISIBLE_NOTIFY_ONLY_COMPLETION = 3;

        /** can take any of the following values: {@link #VISIBILITY_HIDDEN}
         * {@link #VISIBILITY_VISIBLE_NOTIFY_COMPLETED}, {@link #VISIBILITY_VISIBLE},
         * {@link #VISIBILITY_VISIBLE_NOTIFY_ONLY_COMPLETION}
         */
        private int mNotificationVisibility = VISIBILITY_VISIBLE;

        /**
         * @param uri the HTTP or HTTPS URI to download.
         */
        public Request(Uri uri) {
            if (uri == null) {
                throw new NullPointerException();
            }
            String scheme = uri.getScheme();
            if (scheme == null || (!scheme.equals("http") && !scheme.equals("https"))) {
                throw new IllegalArgumentException("Can only download HTTP/HTTPS URIs: " + uri);
            }
            mUri = uri;
        }

        Request(String uriString) {
            mUri = Uri.parse(uriString);
        }

        /**
         * Set the local destination for the downloaded file. Must be a file URI to a path on
         * external storage, and the calling application must have the WRITE_EXTERNAL_STORAGE
         * permission.
         * <p>
         * The downloaded file is not scanned by MediaScanner.
         * But it can be made scannable by calling {@link #allowScanningByMediaScanner()}.
         * <p>
         * By default, downloads are saved to a generated filename in the shared download cache and
         * may be deleted by the system at any time to reclaim space.
         *
         * @return this object
         */
        public Request setDestinationUri(Uri uri) {
            mDestinationUri = uri;
            return this;
        }

        /**
         * Set the local destination for the downloaded file to the system cache dir (/cache).
         * This is only available to System apps with the permission
         * {@link android.Manifest.permission#ACCESS_CACHE_FILESYSTEM}.
         * <p>
         * The downloaded file is not scanned by MediaScanner.
         * But it can be made scannable by calling {@link #allowScanningByMediaScanner()}.
         * <p>
         * Files downloaded to /cache may be deleted by the system at any time to reclaim space.
         *
         * @return this object
         * @hide
         */
        public Request setDestinationToSystemCache() {
            mUseSystemCache = true;
            return this;
        }

        /**
         * Set the local destination for the downloaded file to a path within
         * the application's external files directory (as returned by
         * {@link Context#getExternalFilesDir(String)}.
         * <p>
         * The downloaded file is not scanned by MediaScanner. But it can be
         * made scannable by calling {@link #allowScanningByMediaScanner()}.
         *
         * @param context the {@link Context} to use in determining the external
         *            files directory
         * @param dirType the directory type to pass to
         *            {@link Context#getExternalFilesDir(String)}
         * @param subPath the path within the external directory, including the
         *            destination filename
         * @return this object
         * @throws IllegalStateException If the external storage directory
         *             cannot be found or created.
         */
        public Request setDestinationInExternalFilesDir(Context context, String dirType,
                String subPath) {
            final File file = context.getExternalFilesDir(dirType);
            if (file == null) {
                throw new IllegalStateException("Failed to get external storage files directory");
            } else if (file.exists()) {
                if (!file.isDirectory()) {
                    throw new IllegalStateException(file.getAbsolutePath() +
                            " already exists and is not a directory");
                }
            } else {
                if (!file.mkdirs()) {
                    throw new IllegalStateException("Unable to create directory: "+
                            file.getAbsolutePath());
                }
            }
            setDestinationFromBase(file, subPath);
            return this;
        }

        /**
         * Set the local destination for the downloaded file to a path within
         * the public external storage directory (as returned by
         * {@link Environment#getExternalStoragePublicDirectory(String)}).
         * <p>
         * The downloaded file is not scanned by MediaScanner. But it can be
         * made scannable by calling {@link #allowScanningByMediaScanner()}.
         *
         * @param dirType the directory type to pass to {@link Environment#getExternalStoragePublicDirectory(String)}
         * @param subPath the path within the external directory, including the
         *            destination filename
         * @return this object
         * @throws IllegalStateException If the external storage directory
         *             cannot be found or created.
         */
        public Request setDestinationInExternalPublicDir(String dirType, String subPath) {
            File file = Environment.getExternalStoragePublicDirectory(dirType);
            if (file == null) {
                throw new IllegalStateException("Failed to get external storage public directory");
            } else if (file.exists()) {
                if (!file.isDirectory()) {
                    throw new IllegalStateException(file.getAbsolutePath() +
                            " already exists and is not a directory");
                }
            } else {
                if (!file.mkdirs()) {
                    throw new IllegalStateException("Unable to create directory: "+
                            file.getAbsolutePath());
                }
            }
            setDestinationFromBase(file, subPath);
            return this;
        }

        private void setDestinationFromBase(File base, String subPath) {
            if (subPath == null) {
                throw new NullPointerException("subPath cannot be null");
            }
            mDestinationUri = Uri.withAppendedPath(Uri.fromFile(base), subPath);
        }

        /**
         * If the file to be downloaded is to be scanned by MediaScanner, this method
         * should be called before {@link DownloadManager#enqueue(Request)} is called.
         */
        public void allowScanningByMediaScanner() {
            mScannable = true;
        }

        /**
         * Add an HTTP header to be included with the download request.  The header will be added to
         * the end of the list.
         * @param header HTTP header name
         * @param value header value
         * @return this object
         * @see <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2">HTTP/1.1
         *      Message Headers</a>
         */
        public Request addRequestHeader(String header, String value) {
            if (header == null) {
                throw new NullPointerException("header cannot be null");
            }
            if (header.contains(":")) {
                throw new IllegalArgumentException("header may not contain ':'");
            }
            if (value == null) {
                value = "";
            }
            mRequestHeaders.add(Pair.create(header, value));
            return this;
        }

        /**
         * Set the title of this download, to be displayed in notifications (if enabled).  If no
         * title is given, a default one will be assigned based on the download filename, once the
         * download starts.
         * @return this object
         */
        public Request setTitle(CharSequence title) {
            mTitle = title;
            return this;
        }

        /**
         * Set a description of this download, to be displayed in notifications (if enabled)
         * @return this object
         */
        public Request setDescription(CharSequence description) {
            mDescription = description;
            return this;
        }

        /**
         * Set the MIME content type of this download.  This will override the content type declared
         * in the server's response.
         * @see <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.7">HTTP/1.1
         *      Media Types</a>
         * @return this object
         */
        public Request setMimeType(String mimeType) {
            mMimeType = mimeType;
            return this;
        }

        /**
         * Control whether a system notification is posted by the download manager while this
         * download is running. If enabled, the download manager posts notifications about downloads
         * through the system {@link android.app.NotificationManager}. By default, a notification is
         * shown.
         *
         * If set to false, this requires the permission
         * android.permission.DOWNLOAD_WITHOUT_NOTIFICATION.
         *
         * @param show whether the download manager should show a notification for this download.
         * @return this object
         * @deprecated use {@link #setNotificationVisibility(int)}
         */
        @Deprecated
        public Request setShowRunningNotification(boolean show) {
            return (show) ? setNotificationVisibility(VISIBILITY_VISIBLE) :
                    setNotificationVisibility(VISIBILITY_HIDDEN);
        }

        /**
         * Control whether a system notification is posted by the download manager while this
         * download is running or when it is completed.
         * If enabled, the download manager posts notifications about downloads
         * through the system {@link android.app.NotificationManager}.
         * By default, a notification is shown only when the download is in progress.
         *<p>
         * It can take the following values: {@link #VISIBILITY_HIDDEN},
         * {@link #VISIBILITY_VISIBLE},
         * {@link #VISIBILITY_VISIBLE_NOTIFY_COMPLETED}.
         *<p>
         * If set to {@link #VISIBILITY_HIDDEN}, this requires the permission
         * android.permission.DOWNLOAD_WITHOUT_NOTIFICATION.
         *
         * @param visibility the visibility setting value
         * @return this object
         */
        public Request setNotificationVisibility(int visibility) {
            mNotificationVisibility = visibility;
            return this;
        }

        /**
         * Restrict the types of networks over which this download may proceed.
         * By default, all network types are allowed. Consider using
         * {@link #setAllowedOverMetered(boolean)} instead, since it's more
         * flexible.
         *
         * @param flags any combination of the NETWORK_* bit flags.
         * @return this object
         */
        public Request setAllowedNetworkTypes(int flags) {
            mAllowedNetworkTypes = flags;
            return this;
        }

        /**
         * Set whether this download may proceed over a roaming connection.  By default, roaming is
         * allowed.
         * @param allowed whether to allow a roaming connection to be used
         * @return this object
         */
        public Request setAllowedOverRoaming(boolean allowed) {
            mRoamingAllowed = allowed;
            return this;
        }

        /**
         * Set whether this download may proceed over a metered network
         * connection. By default, metered networks are allowed.
         *
         * @see ConnectivityManager#isActiveNetworkMetered()
         */
        public Request setAllowedOverMetered(boolean allow) {
            mMeteredAllowed = allow;
            return this;
        }

        /**
         * Set whether this download should be displayed in the system's Downloads UI. True by
         * default.
         * @param isVisible whether to display this download in the Downloads UI
         * @return this object
         */
        public Request setVisibleInDownloadsUi(boolean isVisible) {
            mIsVisibleInDownloadsUi = isVisible;
            return this;
        }

        /**
         * @return ContentValues to be passed to DownloadProvider.insert()
         */
        ContentValues toContentValues(String packageName) {
            ContentValues values = new ContentValues();
            assert mUri != null;
            values.put(Downloads.Impl.COLUMN_URI, mUri.toString());
            values.put(Downloads.Impl.COLUMN_IS_PUBLIC_API, true);
            values.put(Downloads.Impl.COLUMN_NOTIFICATION_PACKAGE, packageName);

            if (mDestinationUri != null) {
                values.put(Downloads.Impl.COLUMN_DESTINATION, Downloads.Impl.DESTINATION_FILE_URI);
                values.put(Downloads.Impl.COLUMN_FILE_NAME_HINT, mDestinationUri.toString());
            } else {
                values.put(Downloads.Impl.COLUMN_DESTINATION,
                           (this.mUseSystemCache) ?
                                   Downloads.Impl.DESTINATION_SYSTEMCACHE_PARTITION :
                                   Downloads.Impl.DESTINATION_CACHE_PARTITION_PURGEABLE);
            }
            // is the file supposed to be media-scannable?
            values.put(Downloads.Impl.COLUMN_MEDIA_SCANNED, (mScannable) ? SCANNABLE_VALUE_YES :
                    SCANNABLE_VALUE_NO);

            if (!mRequestHeaders.isEmpty()) {
                encodeHttpHeaders(values);
            }

            putIfNonNull(values, Downloads.Impl.COLUMN_TITLE, mTitle);
            putIfNonNull(values, Downloads.Impl.COLUMN_DESCRIPTION, mDescription);
            putIfNonNull(values, Downloads.Impl.COLUMN_MIME_TYPE, mMimeType);

            values.put(Downloads.Impl.COLUMN_VISIBILITY, mNotificationVisibility);
            values.put(Downloads.Impl.COLUMN_ALLOWED_NETWORK_TYPES, mAllowedNetworkTypes);
            values.put(Downloads.Impl.COLUMN_ALLOW_ROAMING, mRoamingAllowed);
            values.put(Downloads.Impl.COLUMN_ALLOW_METERED, mMeteredAllowed);
            values.put(Downloads.Impl.COLUMN_IS_VISIBLE_IN_DOWNLOADS_UI, mIsVisibleInDownloadsUi);

            return values;
        }

        private void encodeHttpHeaders(ContentValues values) {
            int index = 0;
            for (Pair<String, String> header : mRequestHeaders) {
                String headerString = header.first + ": " + header.second;
                values.put(Downloads.Impl.RequestHeaders.INSERT_KEY_PREFIX + index, headerString);
                index++;
            }
        }

        private void putIfNonNull(ContentValues contentValues, String key, Object value) {
            if (value != null) {
                contentValues.put(key, value.toString());
            }
        }
    }

    /**
     * This class may be used to filter download manager queries.
     */
    public static class Query {
        /**
         * Constant for use with {@link #orderBy}
         * @hide
         */
        public static final int ORDER_ASCENDING = 1;

        /**
         * Constant for use with {@link #orderBy}
         * @hide
         */
        public static final int ORDER_DESCENDING = 2;

        private long[] mIds = null;
        private Integer mStatusFlags = null;
        private String mOrderByColumn = Downloads.Impl.COLUMN_LAST_MODIFICATION;
        private int mOrderDirection = ORDER_DESCENDING;
        private boolean mOnlyIncludeVisibleInDownloadsUi = false;

        /**
         * Include only the downloads with the given IDs.
         * @return this object
         */
        public Query setFilterById(long... ids) {
            mIds = ids;
            return this;
        }

        /**
         * Include only downloads with status matching any the given status flags.
         * @param flags any combination of the STATUS_* bit flags
         * @return this object
         */
        public Query setFilterByStatus(int flags) {
            mStatusFlags = flags;
            return this;
        }

        /**
         * Controls whether this query includes downloads not visible in the system's Downloads UI.
         * @param value if true, this query will only include downloads that should be displayed in
         *            the system's Downloads UI; if false (the default), this query will include
         *            both visible and invisible downloads.
         * @return this object
         * @hide
         */
        public Query setOnlyIncludeVisibleInDownloadsUi(boolean value) {
            mOnlyIncludeVisibleInDownloadsUi = value;
            return this;
        }

        /**
         * Change the sort order of the returned Cursor.
         *
         * @param column one of the COLUMN_* constants; currently, only
         *         {@link #COLUMN_LAST_MODIFIED_TIMESTAMP} and {@link #COLUMN_TOTAL_SIZE_BYTES} are
         *         supported.
         * @param direction either {@link #ORDER_ASCENDING} or {@link #ORDER_DESCENDING}
         * @return this object
         * @hide
         */
        public Query orderBy(String column, int direction) {
            if (direction != ORDER_ASCENDING && direction != ORDER_DESCENDING) {
                throw new IllegalArgumentException("Invalid direction: " + direction);
            }

            if (column.equals(COLUMN_LAST_MODIFIED_TIMESTAMP)) {
                mOrderByColumn = Downloads.Impl.COLUMN_LAST_MODIFICATION;
            } else if (column.equals(COLUMN_TOTAL_SIZE_BYTES)) {
                mOrderByColumn = Downloads.Impl.COLUMN_TOTAL_BYTES;
            } else {
                throw new IllegalArgumentException("Cannot order by " + column);
            }
            mOrderDirection = direction;
            return this;
        }

        /**
         * Run this query using the given ContentResolver.
         * @param projection the projection to pass to ContentResolver.query()
         * @return the Cursor returned by ContentResolver.query()
         */
        Cursor runQuery(ContentResolver resolver, String[] projection, Uri baseUri) {
            Uri uri = baseUri;
            List<String> selectionParts = new ArrayList<String>();
            String[] selectionArgs = null;

            if (mIds != null) {
                selectionParts.add(getWhereClauseForIds(mIds));
                selectionArgs = getWhereArgsForIds(mIds);
            }

            if (mStatusFlags != null) {
                List<String> parts = new ArrayList<String>();
                if ((mStatusFlags & STATUS_PENDING) != 0) {
                    parts.add(statusClause("=", Downloads.Impl.STATUS_PENDING));
                }
                if ((mStatusFlags & STATUS_RUNNING) != 0) {
                    parts.add(statusClause("=", Downloads.Impl.STATUS_RUNNING));
                }
                if ((mStatusFlags & STATUS_PAUSED) != 0) {
                    parts.add(statusClause("=", Downloads.Impl.STATUS_PAUSED_BY_APP));
                    parts.add(statusClause("=", Downloads.Impl.STATUS_WAITING_TO_RETRY));
                    parts.add(statusClause("=", Downloads.Impl.STATUS_WAITING_FOR_NETWORK));
                    parts.add(statusClause("=", Downloads.Impl.STATUS_QUEUED_FOR_WIFI));
                }
                if ((mStatusFlags & STATUS_SUCCESSFUL) != 0) {
                    parts.add(statusClause("=", Downloads.Impl.STATUS_SUCCESS));
                }
                if ((mStatusFlags & STATUS_FAILED) != 0) {
                    parts.add("(" + statusClause(">=", 400)
                              + " AND " + statusClause("<", 600) + ")");
                }
                selectionParts.add(joinStrings(" OR ", parts));
            }

            if (mOnlyIncludeVisibleInDownloadsUi) {
                selectionParts.add(Downloads.Impl.COLUMN_IS_VISIBLE_IN_DOWNLOADS_UI + " != '0'");
            }

            // only return rows which are not marked 'deleted = 1'
            selectionParts.add(Downloads.Impl.COLUMN_DELETED + " != '1'");

            String selection = joinStrings(" AND ", selectionParts);
            String orderDirection = (mOrderDirection == ORDER_ASCENDING ? "ASC" : "DESC");
            String orderBy = mOrderByColumn + " " + orderDirection;

            return resolver.query(uri, projection, selection, selectionArgs, orderBy);
        }

        private String joinStrings(String joiner, Iterable<String> parts) {
            StringBuilder builder = new StringBuilder();
            boolean first = true;
            for (String part : parts) {
                if (!first) {
                    builder.append(joiner);
                }
                builder.append(part);
                first = false;
            }
            return builder.toString();
        }

        private String statusClause(String operator, int value) {
            return Downloads.Impl.COLUMN_STATUS + operator + "'" + value + "'";
        }
    }

    private ContentResolver mResolver;
    private String mPackageName;
    private Uri mBaseUri = Downloads.Impl.CONTENT_URI;

    /**
     * @hide
     */
    public DownloadManager(ContentResolver resolver, String packageName) {
        mResolver = resolver;
        mPackageName = packageName;
    }

    /**
     * Makes this object access the download provider through /all_downloads URIs rather than
     * /my_downloads URIs, for clients that have permission to do so.
     * @hide
     */
    public void setAccessAllDownloads(boolean accessAllDownloads) {
        if (accessAllDownloads) {
            mBaseUri = Downloads.Impl.ALL_DOWNLOADS_CONTENT_URI;
        } else {
            mBaseUri = Downloads.Impl.CONTENT_URI;
        }
    }

    /**
     * Enqueue a new download.  The download will start automatically once the download manager is
     * ready to execute it and connectivity is available.
     *
     * @param request the parameters specifying this download
     * @return an ID for the download, unique across the system.  This ID is used to make future
     * calls related to this download.
     */
    public long enqueue(Request request) {
        ContentValues values = request.toContentValues(mPackageName);
        Uri downloadUri = mResolver.insert(Downloads.Impl.CONTENT_URI, values);
        long id = Long.parseLong(downloadUri.getLastPathSegment());
        return id;
    }

    /**
     * Marks the specified download as 'to be deleted'. This is done when a completed download
     * is to be removed but the row was stored without enough info to delete the corresponding
     * metadata from Mediaprovider database. Actual cleanup of this row is done in DownloadService.
     *
     * @param ids the IDs of the downloads to be marked 'deleted'
     * @return the number of downloads actually updated
     * @hide
     */
    public int markRowDeleted(long... ids) {
        if (ids == null || ids.length == 0) {
            // called with nothing to remove!
            throw new IllegalArgumentException("input param 'ids' can't be null");
        }
        ContentValues values = new ContentValues();
        values.put(Downloads.Impl.COLUMN_DELETED, 1);
        // if only one id is passed in, then include it in the uri itself.
        // this will eliminate a full database scan in the download service.
        if (ids.length == 1) {
            return mResolver.update(ContentUris.withAppendedId(mBaseUri, ids[0]), values,
                    null, null);
        } 
        return mResolver.update(mBaseUri, values, getWhereClauseForIds(ids),
                getWhereArgsForIds(ids));
    }

    /**
     * Cancel downloads and remove them from the download manager.  Each download will be stopped if
     * it was running, and it will no longer be accessible through the download manager.
     * If there is a downloaded file, partial or complete, it is deleted.
     *
     * @param ids the IDs of the downloads to remove
     * @return the number of downloads actually removed
     */
    public int remove(long... ids) {
        return markRowDeleted(ids);
    }

    /**
     * Query the download manager about downloads that have been requested.
     * @param query parameters specifying filters for this query
     * @return a Cursor over the result set of downloads, with columns consisting of all the
     * COLUMN_* constants.
     */
    public Cursor query(Query query) {
        Cursor underlyingCursor = query.runQuery(mResolver, UNDERLYING_COLUMNS, mBaseUri);
        if (underlyingCursor == null) {
            return null;
        }
        return new CursorTranslator(underlyingCursor, mBaseUri);
    }

    /**
     * Open a downloaded file for reading.  The download must have completed.
     * @param id the ID of the download
     * @return a read-only {@link ParcelFileDescriptor}
     * @throws FileNotFoundException if the destination file does not already exist
     */
    public ParcelFileDescriptor openDownloadedFile(long id) throws FileNotFoundException {
        return mResolver.openFileDescriptor(getDownloadUri(id), "r");
    }

    /**
     * Returns the {@link Uri} of the given downloaded file id, if the file is
     * downloaded successfully. Otherwise, null is returned.
     *
     * @param id the id of the downloaded file.
     * @return the {@link Uri} of the given downloaded file id, if download was
     *         successful. null otherwise.
     */
    public Uri getUriForDownloadedFile(long id) {
        // to check if the file is in cache, get its destination from the database
        Query query = new Query().setFilterById(id);
        Cursor cursor = null;
        try {
            cursor = query(query);
            if (cursor == null) {
                return null;
            }
            if (cursor.moveToFirst()) {
                int status = cursor.getInt(cursor.getColumnIndexOrThrow(COLUMN_STATUS));
                if (DownloadManager.STATUS_SUCCESSFUL == status) {
                    return ContentUris.withAppendedId(Downloads.Impl.ALL_DOWNLOADS_CONTENT_URI, id);
                }
            }
        } finally {
            if (cursor != null) {
                cursor.close();
            }
        }
        // downloaded file not found or its status is not 'successfully completed'
        return null;
    }

    /**
     * Returns the media type of the given downloaded file id, if the file was
     * downloaded successfully. Otherwise, null is returned.
     *
     * @param id the id of the downloaded file.
     * @return the media type of the given downloaded file id, if download was successful. null
     * otherwise.
     */
    public String getMimeTypeForDownloadedFile(long id) {
        Query query = new Query().setFilterById(id);
        Cursor cursor = null;
        try {
            cursor = query(query);
            if (cursor == null) {
                return null;
            }
            while (cursor.moveToFirst()) {
                return cursor.getString(cursor.getColumnIndexOrThrow(COLUMN_MEDIA_TYPE));
            }
        } finally {
            if (cursor != null) {
                cursor.close();
            }
        }
        // downloaded file not found or its status is not 'successfully completed'
        return null;
    }

    /**
     * Restart the given downloads, which must have already completed (successfully or not).  This
     * method will only work when called from within the download manager's process.
     * @param ids the IDs of the downloads
     * @hide
     */
    public void restartDownload(long... ids) {
        Cursor cursor = query(new Query().setFilterById(ids));
        try {
            for (cursor.moveToFirst(); !cursor.isAfterLast(); cursor.moveToNext()) {
                int status = cursor.getInt(cursor.getColumnIndex(COLUMN_STATUS));
                if (status != STATUS_SUCCESSFUL && status != STATUS_FAILED) {
                    throw new IllegalArgumentException("Cannot restart incomplete download: "
                            + cursor.getLong(cursor.getColumnIndex(COLUMN_ID)));
                }
            }
        } finally {
            cursor.close();
        }

        ContentValues values = new ContentValues();
        values.put(Downloads.Impl.COLUMN_CURRENT_BYTES, 0);
        values.put(Downloads.Impl.COLUMN_TOTAL_BYTES, -1);
        values.putNull(Downloads.Impl._DATA);
        values.put(Downloads.Impl.COLUMN_STATUS, Downloads.Impl.STATUS_PENDING);
        values.put(Downloads.Impl.COLUMN_FAILED_CONNECTIONS, 0);
        mResolver.update(mBaseUri, values, getWhereClauseForIds(ids), getWhereArgsForIds(ids));
    }

    /**
     * Returns maximum size, in bytes, of downloads that may go over a mobile connection; or null if
     * there's no limit
     *
     * @param context the {@link Context} to use for accessing the {@link ContentResolver}
     * @return maximum size, in bytes, of downloads that may go over a mobile connection; or null if
     * there's no limit
     */
    public static Long getMaxBytesOverMobile(Context context) {
        try {
            return Settings.Global.getLong(context.getContentResolver(),
                    Settings.Global.DOWNLOAD_MAX_BYTES_OVER_MOBILE);
        } catch (SettingNotFoundException exc) {
            return null;
        }
    }

    /**
     * Returns recommended maximum size, in bytes, of downloads that may go over a mobile
     * connection; or null if there's no recommended limit.  The user will have the option to bypass
     * this limit.
     *
     * @param context the {@link Context} to use for accessing the {@link ContentResolver}
     * @return recommended maximum size, in bytes, of downloads that may go over a mobile
     * connection; or null if there's no recommended limit.
     */
    public static Long getRecommendedMaxBytesOverMobile(Context context) {
        try {
            return Settings.Global.getLong(context.getContentResolver(),
                    Settings.Global.DOWNLOAD_RECOMMENDED_MAX_BYTES_OVER_MOBILE);
        } catch (SettingNotFoundException exc) {
            return null;
        }
    }

    /** {@hide} */
    public static boolean isActiveNetworkExpensive(Context context) {
        // TODO: connect to NetworkPolicyManager
        return false;
    }

    /** {@hide} */
    public static long getActiveNetworkWarningBytes(Context context) {
        // TODO: connect to NetworkPolicyManager
        return -1;
    }

    /**
     * Adds a file to the downloads database system, so it could appear in Downloads App
     * (and thus become eligible for management by the Downloads App).
     * <p>
     * It is helpful to make the file scannable by MediaScanner by setting the param
     * isMediaScannerScannable to true. It makes the file visible in media managing
     * applications such as Gallery App, which could be a useful purpose of using this API.
     *
     * @param title the title that would appear for this file in Downloads App.
     * @param description the description that would appear for this file in Downloads App.
     * @param isMediaScannerScannable true if the file is to be scanned by MediaScanner. Files
     * scanned by MediaScanner appear in the applications used to view media (for example,
     * Gallery app).
     * @param mimeType mimetype of the file.
     * @param path absolute pathname to the file. The file should be world-readable, so that it can
     * be managed by the Downloads App and any other app that is used to read it (for example,
     * Gallery app to display the file, if the file contents represent a video/image).
     * @param length length of the downloaded file
     * @param showNotification true if a notification is to be sent, false otherwise
     * @return  an ID for the download entry added to the downloads app, unique across the system
     * This ID is used to make future calls related to this download.
     */
    public long addCompletedDownload(String title, String description,
            boolean isMediaScannerScannable, String mimeType, String path, long length,
            boolean showNotification) {
        return addCompletedDownload(title, description, isMediaScannerScannable, mimeType, path,
                length, showNotification, false);
    }

    /** {@hide} */
    public long addCompletedDownload(String title, String description,
            boolean isMediaScannerScannable, String mimeType, String path, long length,
            boolean showNotification, boolean allowWrite) {
        // make sure the input args are non-null/non-zero
        validateArgumentIsNonEmpty("title", title);
        validateArgumentIsNonEmpty("description", description);
        validateArgumentIsNonEmpty("path", path);
        validateArgumentIsNonEmpty("mimeType", mimeType);
        if (length < 0) {
            throw new IllegalArgumentException(" invalid value for param: totalBytes");
        }

        // if there is already an entry with the given path name in downloads.db, return its id
        Request request = new Request(NON_DOWNLOADMANAGER_DOWNLOAD)
                .setTitle(title)
                .setDescription(description)
                .setMimeType(mimeType);
        ContentValues values = request.toContentValues(null);
        values.put(Downloads.Impl.COLUMN_DESTINATION,
                Downloads.Impl.DESTINATION_NON_DOWNLOADMANAGER_DOWNLOAD);
        values.put(Downloads.Impl._DATA, path);
        values.put(Downloads.Impl.COLUMN_STATUS, Downloads.Impl.STATUS_SUCCESS);
        values.put(Downloads.Impl.COLUMN_TOTAL_BYTES, length);
        values.put(Downloads.Impl.COLUMN_MEDIA_SCANNED,
                (isMediaScannerScannable) ? Request.SCANNABLE_VALUE_YES :
                        Request.SCANNABLE_VALUE_NO);
        values.put(Downloads.Impl.COLUMN_VISIBILITY, (showNotification) ?
                Request.VISIBILITY_VISIBLE_NOTIFY_ONLY_COMPLETION : Request.VISIBILITY_HIDDEN);
        values.put(Downloads.Impl.COLUMN_ALLOW_WRITE, allowWrite ? 1 : 0);
        Uri downloadUri = mResolver.insert(Downloads.Impl.CONTENT_URI, values);
        if (downloadUri == null) {
            return -1;
        }
        return Long.parseLong(downloadUri.getLastPathSegment());
    }

    private static final String NON_DOWNLOADMANAGER_DOWNLOAD =
            "non-dwnldmngr-download-dont-retry2download";

    private static void validateArgumentIsNonEmpty(String paramName, String val) {
        if (TextUtils.isEmpty(val)) {
            throw new IllegalArgumentException(paramName + " can't be null");
        }
    }

    /**
     * Get the DownloadProvider URI for the download with the given ID.
     *
     * @hide
     */
    public Uri getDownloadUri(long id) {
        return ContentUris.withAppendedId(Downloads.Impl.ALL_DOWNLOADS_CONTENT_URI, id);
    }

    /**
     * Get a parameterized SQL WHERE clause to select a bunch of IDs.
     */
    static String getWhereClauseForIds(long[] ids) {
        StringBuilder whereClause = new StringBuilder();
        whereClause.append("(");
        for (int i = 0; i < ids.length; i++) {
            if (i > 0) {
                whereClause.append("OR ");
            }
            whereClause.append(Downloads.Impl._ID);
            whereClause.append(" = ? ");
        }
        whereClause.append(")");
        return whereClause.toString();
    }

    /**
     * Get the selection args for a clause returned by {@link #getWhereClauseForIds(long[])}.
     */
    static String[] getWhereArgsForIds(long[] ids) {
        String[] whereArgs = new String[ids.length];
        for (int i = 0; i < ids.length; i++) {
            whereArgs[i] = Long.toString(ids[i]);
        }
        return whereArgs;
    }

    /**
     * This class wraps a cursor returned by DownloadProvider -- the "underlying cursor" -- and
     * presents a different set of columns, those defined in the DownloadManager.COLUMN_* constants.
     * Some columns correspond directly to underlying values while others are computed from
     * underlying data.
     */
    private static class CursorTranslator extends CursorWrapper {
        private Uri mBaseUri;

        public CursorTranslator(Cursor cursor, Uri baseUri) {
            super(cursor);
            mBaseUri = baseUri;
        }

        @Override
        public int getInt(int columnIndex) {
            return (int) getLong(columnIndex);
        }

        @Override
        public long getLong(int columnIndex) {
            if (getColumnName(columnIndex).equals(COLUMN_REASON)) {
                return getReason(super.getInt(getColumnIndex(Downloads.Impl.COLUMN_STATUS)));
            } else if (getColumnName(columnIndex).equals(COLUMN_STATUS)) {
                return translateStatus(super.getInt(getColumnIndex(Downloads.Impl.COLUMN_STATUS)));
            } else {
                return super.getLong(columnIndex);
            }
        }

        @Override
        public String getString(int columnIndex) {
            return (getColumnName(columnIndex).equals(COLUMN_LOCAL_URI)) ? getLocalUri() :
                    super.getString(columnIndex);
        }

        private String getLocalUri() {
            long destinationType = getLong(getColumnIndex(Downloads.Impl.COLUMN_DESTINATION));
            if (destinationType == Downloads.Impl.DESTINATION_FILE_URI ||
                    destinationType == Downloads.Impl.DESTINATION_EXTERNAL ||
                    destinationType == Downloads.Impl.DESTINATION_NON_DOWNLOADMANAGER_DOWNLOAD) {
                String localPath = getString(getColumnIndex(COLUMN_LOCAL_FILENAME));
                if (localPath == null) {
                    return null;
                }
                return Uri.fromFile(new File(localPath)).toString();
            }

            // return content URI for cache download
            long downloadId = getLong(getColumnIndex(Downloads.Impl._ID));
            return ContentUris.withAppendedId(Downloads.Impl.ALL_DOWNLOADS_CONTENT_URI, downloadId).toString();
        }

        private long getReason(int status) {
            switch (translateStatus(status)) {
                case STATUS_FAILED:
                    return getErrorCode(status);

                case STATUS_PAUSED:
                    return getPausedReason(status);

                default:
                    return 0; // arbitrary value when status is not an error
            }
        }

        private long getPausedReason(int status) {
            switch (status) {
                case Downloads.Impl.STATUS_WAITING_TO_RETRY:
                    return PAUSED_WAITING_TO_RETRY;

                case Downloads.Impl.STATUS_WAITING_FOR_NETWORK:
                    return PAUSED_WAITING_FOR_NETWORK;

                case Downloads.Impl.STATUS_QUEUED_FOR_WIFI:
                    return PAUSED_QUEUED_FOR_WIFI;

                default:
                    return PAUSED_UNKNOWN;
            }
        }

        private long getErrorCode(int status) {
            if ((400 <= status && status < Downloads.Impl.MIN_ARTIFICIAL_ERROR_STATUS)
                    || (500 <= status && status < 600)) {
                // HTTP status code
                return status;
            }

            switch (status) {
                case Downloads.Impl.STATUS_FILE_ERROR:
                    return ERROR_FILE_ERROR;

                case Downloads.Impl.STATUS_UNHANDLED_HTTP_CODE:
                case Downloads.Impl.STATUS_UNHANDLED_REDIRECT:
                    return ERROR_UNHANDLED_HTTP_CODE;

                case Downloads.Impl.STATUS_HTTP_DATA_ERROR:
                    return ERROR_HTTP_DATA_ERROR;

                case Downloads.Impl.STATUS_TOO_MANY_REDIRECTS:
                    return ERROR_TOO_MANY_REDIRECTS;

                case Downloads.Impl.STATUS_INSUFFICIENT_SPACE_ERROR:
                    return ERROR_INSUFFICIENT_SPACE;

                case Downloads.Impl.STATUS_DEVICE_NOT_FOUND_ERROR:
                    return ERROR_DEVICE_NOT_FOUND;

                case Downloads.Impl.STATUS_CANNOT_RESUME:
                    return ERROR_CANNOT_RESUME;

                case Downloads.Impl.STATUS_FILE_ALREADY_EXISTS_ERROR:
                    return ERROR_FILE_ALREADY_EXISTS;

                default:
                    return ERROR_UNKNOWN;
            }
        }

        private int translateStatus(int status) {
            switch (status) {
                case Downloads.Impl.STATUS_PENDING:
                    return STATUS_PENDING;

                case Downloads.Impl.STATUS_RUNNING:
                    return STATUS_RUNNING;

                case Downloads.Impl.STATUS_PAUSED_BY_APP:
                case Downloads.Impl.STATUS_WAITING_TO_RETRY:
                case Downloads.Impl.STATUS_WAITING_FOR_NETWORK:
                case Downloads.Impl.STATUS_QUEUED_FOR_WIFI:
                    return STATUS_PAUSED;

                case Downloads.Impl.STATUS_SUCCESS:
                    return STATUS_SUCCESSFUL;

                default:
                    assert Downloads.Impl.isStatusError(status);
                    return STATUS_FAILED;
            }
        }
    }
}