ConversationCursor.java revision 2cdaa04b0ef7faf02a47ed25215c5b20fa5b219d
1/******************************************************************************* 2 * Copyright (C) 2012 Google Inc. 3 * Licensed to The Android Open Source Project. 4 * 5 * Licensed under the Apache License, Version 2.0 (the "License"); 6 * you may not use this file except in compliance with the License. 7 * You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 *******************************************************************************/ 17 18package com.android.mail.browse; 19 20import android.app.Activity; 21import android.content.ContentProvider; 22import android.content.ContentProviderOperation; 23import android.content.ContentResolver; 24import android.content.ContentValues; 25import android.content.OperationApplicationException; 26import android.database.CharArrayBuffer; 27import android.database.ContentObserver; 28import android.database.Cursor; 29import android.database.DataSetObserver; 30import android.net.Uri; 31import android.os.Bundle; 32import android.os.Looper; 33import android.os.RemoteException; 34import android.util.Log; 35 36import com.android.mail.providers.Conversation; 37import com.android.mail.providers.UIProvider; 38import com.android.mail.providers.UIProvider.ConversationOperations; 39import com.android.mail.utils.LogUtils; 40import com.google.common.annotations.VisibleForTesting; 41 42import java.util.ArrayList; 43import java.util.HashMap; 44import java.util.Iterator; 45import java.util.List; 46 47/** 48 * ConversationCursor is a wrapper around a conversation list cursor that provides update/delete 49 * caching for quick UI response. This is effectively a singleton class, as the cache is 50 * implemented as a static HashMap. 51 */ 52public final class ConversationCursor implements Cursor { 53 private static final String TAG = "ConversationCursor"; 54 private static final boolean DEBUG = true; // STOPSHIP Set to false before shipping 55 56 // The cursor instantiator's activity 57 private static Activity sActivity; 58 // The cursor underlying the caching cursor 59 @VisibleForTesting 60 static Cursor sUnderlyingCursor; 61 // The new cursor obtained via a requery 62 private static Cursor sRequeryCursor; 63 // A mapping from Uri to updated ContentValues 64 private static HashMap<String, ContentValues> sCacheMap = new HashMap<String, ContentValues>(); 65 // Cache map lock (will be used only very briefly - few ms at most) 66 private static Object sCacheMapLock = new Object(); 67 // A deleted row is indicated by the presence of DELETED_COLUMN in the cache map 68 private static final String DELETED_COLUMN = "__deleted__"; 69 // An row cached during a requery is indicated by the presence of REQUERY_COLUMN in the map 70 private static final String REQUERY_COLUMN = "__requery__"; 71 // A sentinel value for the "index" of the deleted column; it's an int that is otherwise invalid 72 private static final int DELETED_COLUMN_INDEX = -1; 73 // Empty deletion list 74 private static final ArrayList<Integer> EMPTY_DELETION_LIST = new ArrayList<Integer>(); 75 // The current conversation cursor 76 private static ConversationCursor sConversationCursor; 77 // The index of the Uri whose data is reflected in the cached row 78 // Updates/Deletes to this Uri are cached 79 private static int sUriColumnIndex; 80 // The listeners registered for this cursor 81 private static ArrayList<ConversationListener> sListeners = 82 new ArrayList<ConversationListener>(); 83 // The ConversationProvider instance 84 @VisibleForTesting 85 static ConversationProvider sProvider; 86 // Set when we're in the middle of a refresh of the underlying cursor 87 private static boolean sRefreshInProgress = false; 88 // Set when we've sent refreshReady() to listeners 89 private static boolean sRefreshReady = false; 90 // Set when we've sent refreshRequired() to listeners 91 private static boolean sRefreshRequired = false; 92 // Our sequence count (for changes sent to underlying provider) 93 private static int sSequence = 0; 94 95 // Column names for this cursor 96 private final String[] mColumnNames; 97 // The resolver for the cursor instantiator's context 98 private static ContentResolver mResolver; 99 // An observer on the underlying cursor (so we can detect changes from outside the UI) 100 private final CursorObserver mCursorObserver; 101 // Whether our observer is currently registered with the underlying cursor 102 private boolean mCursorObserverRegistered = false; 103 104 // The current position of the cursor 105 private int mPosition = -1; 106 // The number of cached deletions from this cursor (used to quickly generate an accurate count) 107 private static int sDeletedCount = 0; 108 109 // Parameters passed to the underlying query 110 private static Uri qUri; 111 private static String[] qProjection; 112 113 private ConversationCursor(Cursor cursor, Activity activity, String messageListColumn) { 114 sConversationCursor = this; 115 // If we have an existing underlying cursor, make sure it's closed 116 if (sUnderlyingCursor != null) { 117 sUnderlyingCursor.close(); 118 } 119 sUnderlyingCursor = cursor; 120 sListeners.clear(); 121 sRefreshRequired = false; 122 sRefreshReady = false; 123 sRefreshInProgress = false; 124 mCursorObserver = new CursorObserver(); 125 resetCursor(null); 126 mColumnNames = cursor.getColumnNames(); 127 sUriColumnIndex = cursor.getColumnIndex(messageListColumn); 128 if (sUriColumnIndex < 0) { 129 throw new IllegalArgumentException("Cursor must include a message list column"); 130 } 131 } 132 133 /** 134 * Create a ConversationCursor; this should be called by the ListActivity using that cursor 135 * @param activity the activity creating the cursor 136 * @param messageListColumn the column used for individual cursor items 137 * @param uri the query uri 138 * @param projection the query projecion 139 * @param selection the query selection 140 * @param selectionArgs the query selection args 141 * @param sortOrder the query sort order 142 * @return a ConversationCursor 143 */ 144 public static ConversationCursor create(Activity activity, String messageListColumn, Uri uri, 145 String[] projection, String selection, String[] selectionArgs, String sortOrder) { 146 sActivity = activity; 147 mResolver = activity.getContentResolver(); 148 if (selection != null || sortOrder != null) { 149 throw new IllegalArgumentException( 150 "Selection and sort order aren't allowed in ConversationCursors"); 151 } 152 synchronized (sCacheMapLock) { 153 // First, let's see if we already have a cursor 154 if (sConversationCursor != null) { 155 // If it's the same, just clean up 156 if (qUri.equals(uri) && !sRefreshRequired && !sRefreshInProgress) { 157 if (sRefreshReady) { 158 // If we already have a refresh ready, just sync() it 159 LogUtils.i(TAG, "Create: refreshed cursor ready, sync"); 160 } else { 161 // Position the cursor before the first item (as it would be if new), reset 162 // the cache, and return as new 163 LogUtils.i(TAG, "Create: cursor good, reset position and clear map"); 164 sConversationCursor.moveToPosition(-1); 165 sConversationCursor.mPosition = -1; 166 synchronized (sCacheMapLock) { 167 sCacheMap.clear(); 168 } 169 } 170 } else { 171 // Set qUri/qProjection these in case they changed 172 LogUtils.i(TAG, "Create: new query or refresh needed, query/sync"); 173 sRequeryCursor = doQuery(uri, projection); 174 sRefreshReady = true; 175 } 176 return sConversationCursor; 177 } 178 // Create new ConversationCursor 179 LogUtils.i(TAG, "Create: initial creation"); 180 return new ConversationCursor(doQuery(uri, projection), activity, messageListColumn); 181 } 182 } 183 184 private static Cursor doQuery(Uri uri, String[] projection) { 185 qUri = uri; 186 qProjection = projection; 187 if (mResolver == null) { 188 mResolver = sActivity.getContentResolver(); 189 } 190 return mResolver.query(qUri, qProjection, null, null, null); 191 } 192 193 /** 194 * Return whether the uri string (message list uri) is in the underlying cursor 195 * @param uriString the uri string we're looking for 196 * @return true if the uri string is in the cursor; false otherwise 197 */ 198 private boolean isInUnderlyingCursor(String uriString) { 199 sUnderlyingCursor.moveToPosition(-1); 200 while (sUnderlyingCursor.moveToNext()) { 201 if (uriString.equals(sUnderlyingCursor.getString(sUriColumnIndex))) { 202 return true; 203 } 204 } 205 return false; 206 } 207 208 /** 209 * Reset the cursor; this involves clearing out our cache map and resetting our various counts 210 * The cursor should be reset whenever we get fresh data from the underlying cursor. The cache 211 * is locked during the reset, which will block the UI, but for only a very short time 212 * (estimated at a few ms, but we can profile this; remember that the cache will usually 213 * be empty or have a few entries) 214 */ 215 private void resetCursor(Cursor newCursor) { 216 // Temporary, log time for reset 217 long startTime = System.currentTimeMillis(); 218 if (DEBUG) { 219 LogUtils.i(TAG, "[--resetCursor--]"); 220 } 221 synchronized (sCacheMapLock) { 222 // Walk through the cache. Here are the cases: 223 // 1) The entry isn't marked with REQUERY - remove it from the cache. If DELETED is 224 // set, decrement the deleted count 225 // 2) The REQUERY entry is still in the UP 226 // 2a) The REQUERY entry isn't DELETED; we're good, and the client change will remain 227 // (i.e. client wins, it's on its way to the UP) 228 // 2b) The REQUERY entry is DELETED; we're good (client change remains, it's on 229 // its way to the UP) 230 // 3) the REQUERY was deleted on the server (sheesh; this would be bizarre timing!) - 231 // we need to throw the item out of the cache 232 // So ... the only interesting case is #3, we need to look for remaining deleted items 233 // and see if they're still in the UP 234 Iterator<HashMap.Entry<String, ContentValues>> iter = sCacheMap.entrySet().iterator(); 235 while (iter.hasNext()) { 236 HashMap.Entry<String, ContentValues> entry = iter.next(); 237 ContentValues values = entry.getValue(); 238 if (values.containsKey(REQUERY_COLUMN) && isInUnderlyingCursor(entry.getKey())) { 239 // If we're in a requery and we're still around, remove the requery key 240 // We're good here, the cached change (delete/update) is on its way to UP 241 values.remove(REQUERY_COLUMN); 242 } else { 243 // Keep the deleted count up-to-date; remove the cache entry 244 if (values.containsKey(DELETED_COLUMN)) { 245 sDeletedCount--; 246 } 247 // Remove the entry 248 iter.remove(); 249 } 250 } 251 252 // Swap cursor 253 if (newCursor != null) { 254 close(); 255 sUnderlyingCursor = newCursor; 256 } 257 258 mPosition = -1; 259 sUnderlyingCursor.moveToPosition(mPosition); 260 if (!mCursorObserverRegistered) { 261 sUnderlyingCursor.registerContentObserver(mCursorObserver); 262 mCursorObserverRegistered = true; 263 } 264 sRefreshRequired = false; 265 } 266 LogUtils.i(TAG, "resetCache time: " + ((System.currentTimeMillis() - startTime)) + "ms"); 267 } 268 269 /** 270 * Add a listener for this cursor; we'll notify it when our data changes 271 */ 272 public void addListener(ConversationListener listener) { 273 synchronized (sListeners) { 274 if (!sListeners.contains(listener)) { 275 sListeners.add(listener); 276 } else { 277 LogUtils.i(TAG, "Ignoring duplicate add of listener"); 278 } 279 } 280 } 281 282 /** 283 * Remove a listener for this cursor 284 */ 285 public void removeListener(ConversationListener listener) { 286 synchronized(sListeners) { 287 sListeners.remove(listener); 288 } 289 } 290 291 /** 292 * Generate a forwarding Uri to ConversationProvider from an original Uri. We do this by 293 * changing the authority to ours, but otherwise leaving the Uri intact. 294 * NOTE: This won't handle query parameters, so the functionality will need to be added if 295 * parameters are used in the future 296 * @param uri the uri 297 * @return a forwarding uri to ConversationProvider 298 */ 299 private static String uriToCachingUriString (Uri uri) { 300 String provider = uri.getAuthority(); 301 return uri.getScheme() + "://" + ConversationProvider.AUTHORITY 302 + "/" + provider + uri.getPath(); 303 } 304 305 /** 306 * Regenerate the original Uri from a forwarding (ConversationProvider) Uri 307 * NOTE: See note above for uriToCachingUri 308 * @param uri the forwarding Uri 309 * @return the original Uri 310 */ 311 private static Uri uriFromCachingUri(Uri uri) { 312 List<String> path = uri.getPathSegments(); 313 Uri.Builder builder = new Uri.Builder().scheme(uri.getScheme()).authority(path.get(0)); 314 for (int i = 1; i < path.size(); i++) { 315 builder.appendPath(path.get(i)); 316 } 317 return builder.build(); 318 } 319 320 /** 321 * Cache a column name/value pair for a given Uri 322 * @param uriString the Uri for which the column name/value pair applies 323 * @param columnName the column name 324 * @param value the value to be cached 325 */ 326 private static void cacheValue(String uriString, String columnName, Object value) { 327 synchronized (sCacheMapLock) { 328 // Get the map for our uri 329 ContentValues map = sCacheMap.get(uriString); 330 // Create one if necessary 331 if (map == null) { 332 map = new ContentValues(); 333 sCacheMap.put(uriString, map); 334 } 335 // If we're caching a deletion, add to our count 336 if ((columnName == DELETED_COLUMN) && (map.get(columnName) == null)) { 337 sDeletedCount++; 338 if (DEBUG) { 339 LogUtils.i(TAG, "Deleted " + uriString); 340 } 341 } 342 // ContentValues has no generic "put", so we must test. For now, the only classes of 343 // values implemented are Boolean/Integer/String, though others are trivially added 344 if (value instanceof Boolean) { 345 map.put(columnName, ((Boolean) value).booleanValue() ? 1 : 0); 346 } else if (value instanceof Integer) { 347 map.put(columnName, (Integer) value); 348 } else if (value instanceof String) { 349 map.put(columnName, (String) value); 350 } else { 351 String cname = value.getClass().getName(); 352 throw new IllegalArgumentException("Value class not compatible with cache: " 353 + cname); 354 } 355 if (sRefreshInProgress) { 356 map.put(REQUERY_COLUMN, 1); 357 } 358 if (DEBUG && (columnName != DELETED_COLUMN)) { 359 LogUtils.i(TAG, "Caching value for " + uriString + ": " + columnName); 360 } 361 } 362 } 363 364 /** 365 * Get the cached value for the provided column; we special case -1 as the "deleted" column 366 * @param columnIndex the index of the column whose cached value we want to retrieve 367 * @return the cached value for this column, or null if there is none 368 */ 369 private Object getCachedValue(int columnIndex) { 370 String uri = sUnderlyingCursor.getString(sUriColumnIndex); 371 ContentValues uriMap = sCacheMap.get(uri); 372 if (uriMap != null) { 373 String columnName; 374 if (columnIndex == DELETED_COLUMN_INDEX) { 375 columnName = DELETED_COLUMN; 376 } else { 377 columnName = mColumnNames[columnIndex]; 378 } 379 return uriMap.get(columnName); 380 } 381 return null; 382 } 383 384 /** 385 * When the underlying cursor changes, we want to alert the listener 386 */ 387 private void underlyingChanged() { 388 if (mCursorObserverRegistered) { 389 try { 390 sUnderlyingCursor.unregisterContentObserver(mCursorObserver); 391 } catch (IllegalStateException e) { 392 // Maybe the cursor was GC'd? 393 } 394 mCursorObserverRegistered = false; 395 } 396 if (DEBUG) { 397 LogUtils.i(TAG, "[Notify: onRefreshRequired()]"); 398 } 399 synchronized(sListeners) { 400 for (ConversationListener listener: sListeners) { 401 listener.onRefreshRequired(); 402 } 403 } 404 sRefreshRequired = true; 405 } 406 407 /** 408 * Put the refreshed cursor in place (called by the UI) 409 */ 410 // NOTE: We don't like the name (it implies syncing with the server); suggestions gladly 411 // taken - reset? syncToUnderlying? completeRefresh? align? 412 public void sync() { 413 synchronized (sCacheMapLock) { 414 if (DEBUG) { 415 LogUtils.i(TAG, "[sync() called]"); 416 } 417 if (sRequeryCursor == null) { 418 // This can happen during an animated deletion, if the UI isn't keeping track 419 // If we have no new data, this is a noop 420 Log.w(TAG, "UI calling sync() out of sequence"); 421 } 422 resetCursor(sRequeryCursor); 423 sRequeryCursor = null; 424 sRefreshInProgress = false; 425 sRefreshReady = false; 426 } 427 } 428 429 public boolean isRefreshRequired() { 430 return sRefreshRequired; 431 } 432 433 public boolean isRefreshReady() { 434 return sRefreshReady; 435 } 436 437 /** 438 * Cancel a refresh in progress 439 */ 440 public void cancelRefresh() { 441 if (DEBUG) { 442 LogUtils.i(TAG, "[cancelRefresh() called]"); 443 } 444 synchronized(sCacheMapLock) { 445 // Mark the requery closed 446 sRefreshInProgress = false; 447 sRefreshReady = false; 448 // If we have the cursor, close it; otherwise, it will get closed when the query 449 // finishes (it checks sRequeryInProgress) 450 if (sRequeryCursor != null) { 451 sRequeryCursor.close(); 452 sRequeryCursor = null; 453 } 454 } 455 } 456 457 /** 458 * Get a list of deletions from ConversationCursor to the refreshed cursor that hasn't yet 459 * been swapped into place; this allows the UI to animate these away if desired 460 * @return a list of positions deleted in ConversationCursor 461 */ 462 public ArrayList<Integer> getRefreshDeletions () { 463 if (DEBUG) { 464 LogUtils.i(TAG, "[getRefreshDeletions() called]"); 465 } 466 // It's possible that the requery cursor is null in the case that loadInBackground() causes 467 // ConversationCursor.create to do a sync() between the time that refreshReady() is called 468 // and the subsequent call to getRefreshDeletions(). This is harmless, and an empty 469 // result list is correct. 470 if (sRequeryCursor == null) { 471 return EMPTY_DELETION_LIST; 472 } 473 Cursor deviceCursor = sConversationCursor; 474 Cursor serverCursor = sRequeryCursor; 475 ArrayList<Integer> deleteList = new ArrayList<Integer>(); 476 int serverCount = serverCursor.getCount(); 477 int deviceCount = deviceCursor.getCount(); 478 deviceCursor.moveToFirst(); 479 serverCursor.moveToFirst(); 480 while (serverCount > 0 || deviceCount > 0) { 481 if (serverCount == 0) { 482 for (; deviceCount > 0; deviceCount--) 483 deleteList.add(deviceCursor.getPosition()); 484 break; 485 } else if (deviceCount == 0) { 486 break; 487 } 488 long deviceMs = deviceCursor.getLong(UIProvider.CONVERSATION_DATE_RECEIVED_MS_COLUMN); 489 long serverMs = serverCursor.getLong(UIProvider.CONVERSATION_DATE_RECEIVED_MS_COLUMN); 490 String deviceUri = deviceCursor.getString(UIProvider.CONVERSATION_URI_COLUMN); 491 String serverUri = serverCursor.getString(UIProvider.CONVERSATION_URI_COLUMN); 492 deviceCursor.moveToNext(); 493 serverCursor.moveToNext(); 494 serverCount--; 495 deviceCount--; 496 if (serverMs == deviceMs) { 497 // Check for duplicates here; if our identical dates refer to different messages, 498 // we'll just quit here for now (at worst, this will cause a non-animating delete) 499 // My guess is that this happens VERY rarely, if at all 500 if (!deviceUri.equals(serverUri)) { 501 // To do this right, we'd find all of the rows with the same ms (date), etc... 502 //return deleteList; 503 } 504 continue; 505 } else if (deviceMs > serverMs) { 506 deleteList.add(deviceCursor.getPosition() - 1); 507 // Move back because we've already advanced cursor (that's why we subtract 1 above) 508 serverCount++; 509 serverCursor.moveToPrevious(); 510 } else if (serverMs > deviceMs) { 511 // If we wanted to track insertions, we'd so so here 512 // Move back because we've already advanced cursor 513 deviceCount++; 514 deviceCursor.moveToPrevious(); 515 } 516 } 517 LogUtils.i(TAG, "Deletions: " + deleteList); 518 return deleteList; 519 } 520 521 /** 522 * When we get a requery from the UI, we'll do it, but also clear the cache. The listener is 523 * notified when the requery is complete 524 * NOTE: This will have to change, of course, when we start using loaders... 525 */ 526 public boolean refresh() { 527 if (DEBUG) { 528 LogUtils.i(TAG, "[refresh() called]"); 529 } 530 if (sRefreshInProgress) { 531 return false; 532 } 533 // Say we're starting a requery 534 sRefreshInProgress = true; 535 new Thread(new Runnable() { 536 @Override 537 public void run() { 538 // Get new data 539 sRequeryCursor = doQuery(qUri, qProjection); 540 // Make sure window is full 541 synchronized(sCacheMapLock) { 542 if (sRefreshInProgress) { 543 sRequeryCursor.getCount(); 544 sRefreshReady = true; 545 sActivity.runOnUiThread(new Runnable() { 546 @Override 547 public void run() { 548 if (DEBUG) { 549 LogUtils.i(TAG, "[Notify: onRefreshReady()]"); 550 } 551 if (sRequeryCursor != null && !sRequeryCursor.isClosed()) { 552 synchronized (sListeners) { 553 for (ConversationListener listener : sListeners) { 554 listener.onRefreshReady(); 555 } 556 } 557 } 558 }}); 559 } else { 560 cancelRefresh(); 561 } 562 } 563 } 564 }).start(); 565 return true; 566 } 567 568 @Override 569 public void close() { 570 if (!sUnderlyingCursor.isClosed()) { 571 // Unregister our observer on the underlying cursor and close as usual 572 if (mCursorObserverRegistered) { 573 try { 574 sUnderlyingCursor.unregisterContentObserver(mCursorObserver); 575 } catch (IllegalStateException e) { 576 // Maybe the cursor got GC'd? 577 } 578 mCursorObserverRegistered = false; 579 } 580 sUnderlyingCursor.close(); 581 } 582 } 583 584 /** 585 * Move to the next not-deleted item in the conversation 586 */ 587 @Override 588 public boolean moveToNext() { 589 while (true) { 590 boolean ret = sUnderlyingCursor.moveToNext(); 591 if (!ret) return false; 592 if (getCachedValue(DELETED_COLUMN_INDEX) instanceof Integer) continue; 593 mPosition++; 594 return true; 595 } 596 } 597 598 /** 599 * Move to the previous not-deleted item in the conversation 600 */ 601 @Override 602 public boolean moveToPrevious() { 603 while (true) { 604 boolean ret = sUnderlyingCursor.moveToPrevious(); 605 if (!ret) return false; 606 if (getCachedValue(-1) instanceof Integer) continue; 607 mPosition--; 608 return true; 609 } 610 } 611 612 @Override 613 public int getPosition() { 614 return mPosition; 615 } 616 617 /** 618 * The actual cursor's count must be decremented by the number we've deleted from the UI 619 */ 620 @Override 621 public int getCount() { 622 return sUnderlyingCursor.getCount() - sDeletedCount; 623 } 624 625 @Override 626 public boolean moveToFirst() { 627 sUnderlyingCursor.moveToPosition(-1); 628 mPosition = -1; 629 return moveToNext(); 630 } 631 632 @Override 633 public boolean moveToPosition(int pos) { 634 if (pos < -1 || pos >= getCount()) return false; 635 if (pos == mPosition) return true; 636 if (pos > mPosition) { 637 while (pos > mPosition) { 638 if (!moveToNext()) { 639 return false; 640 } 641 } 642 return true; 643 } else if (pos == 0) { 644 return moveToFirst(); 645 } else { 646 while (pos < mPosition) { 647 if (!moveToPrevious()) { 648 return false; 649 } 650 } 651 return true; 652 } 653 } 654 655 @Override 656 public boolean moveToLast() { 657 throw new UnsupportedOperationException("moveToLast unsupported!"); 658 } 659 660 @Override 661 public boolean move(int offset) { 662 throw new UnsupportedOperationException("move unsupported!"); 663 } 664 665 /** 666 * We need to override all of the getters to make sure they look at cached values before using 667 * the values in the underlying cursor 668 */ 669 @Override 670 public double getDouble(int columnIndex) { 671 Object obj = getCachedValue(columnIndex); 672 if (obj != null) return (Double)obj; 673 return sUnderlyingCursor.getDouble(columnIndex); 674 } 675 676 @Override 677 public float getFloat(int columnIndex) { 678 Object obj = getCachedValue(columnIndex); 679 if (obj != null) return (Float)obj; 680 return sUnderlyingCursor.getFloat(columnIndex); 681 } 682 683 @Override 684 public int getInt(int columnIndex) { 685 Object obj = getCachedValue(columnIndex); 686 if (obj != null) return (Integer)obj; 687 return sUnderlyingCursor.getInt(columnIndex); 688 } 689 690 @Override 691 public long getLong(int columnIndex) { 692 Object obj = getCachedValue(columnIndex); 693 if (obj != null) return (Long)obj; 694 return sUnderlyingCursor.getLong(columnIndex); 695 } 696 697 @Override 698 public short getShort(int columnIndex) { 699 Object obj = getCachedValue(columnIndex); 700 if (obj != null) return (Short)obj; 701 return sUnderlyingCursor.getShort(columnIndex); 702 } 703 704 @Override 705 public String getString(int columnIndex) { 706 // If we're asking for the Uri for the conversation list, we return a forwarding URI 707 // so that we can intercept update/delete and handle it ourselves 708 if (columnIndex == sUriColumnIndex) { 709 Uri uri = Uri.parse(sUnderlyingCursor.getString(columnIndex)); 710 return uriToCachingUriString(uri); 711 } 712 Object obj = getCachedValue(columnIndex); 713 if (obj != null) return (String)obj; 714 return sUnderlyingCursor.getString(columnIndex); 715 } 716 717 @Override 718 public byte[] getBlob(int columnIndex) { 719 Object obj = getCachedValue(columnIndex); 720 if (obj != null) return (byte[])obj; 721 return sUnderlyingCursor.getBlob(columnIndex); 722 } 723 724 /** 725 * Observer of changes to underlying data 726 */ 727 private class CursorObserver extends ContentObserver { 728 public CursorObserver() { 729 super(null); 730 } 731 732 @Override 733 public void onChange(boolean selfChange) { 734 // If we're here, then something outside of the UI has changed the data, and we 735 // must query the underlying provider for that data 736 if (DEBUG) { 737 LogUtils.i(TAG, "Underlying conversation cursor changed; requerying"); 738 } 739 // It's not at all obvious to me why we must unregister/re-register after the requery 740 // However, if we don't we'll only get one notification and no more... 741 ConversationCursor.this.underlyingChanged(); 742 } 743 } 744 745 /** 746 * ConversationProvider is the ContentProvider for our forwarding Uri's; it passes queries 747 * and inserts directly, and caches updates/deletes before passing them through. The caching 748 * will cause a redraw of the list with updated values. 749 */ 750 public abstract static class ConversationProvider extends ContentProvider { 751 public static String AUTHORITY; 752 753 /** 754 * Allows the implmenting provider to specify the authority that should be used. 755 */ 756 protected abstract String getAuthority(); 757 758 @Override 759 public boolean onCreate() { 760 sProvider = this; 761 AUTHORITY = getAuthority(); 762 return true; 763 } 764 765 @Override 766 public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, 767 String sortOrder) { 768 return mResolver.query( 769 uriFromCachingUri(uri), projection, selection, selectionArgs, sortOrder); 770 } 771 772 @Override 773 public Uri insert(Uri uri, ContentValues values) { 774 insertLocal(uri, values); 775 return ProviderExecute.opInsert(uri, values); 776 } 777 778 @Override 779 public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) { 780 updateLocal(uri, values); 781 return ProviderExecute.opUpdate(uri, values); 782 } 783 784 @Override 785 public int delete(Uri uri, String selection, String[] selectionArgs) { 786 deleteLocal(uri); 787 return ProviderExecute.opDelete(uri); 788 } 789 790 @Override 791 public String getType(Uri uri) { 792 return null; 793 } 794 795 /** 796 * Quick and dirty class that executes underlying provider CRUD operations on a background 797 * thread. 798 */ 799 static class ProviderExecute implements Runnable { 800 static final int DELETE = 0; 801 static final int INSERT = 1; 802 static final int UPDATE = 2; 803 804 final int mCode; 805 final Uri mUri; 806 final ContentValues mValues; //HEHEH 807 808 ProviderExecute(int code, Uri uri, ContentValues values) { 809 mCode = code; 810 mUri = uriFromCachingUri(uri); 811 mValues = values; 812 } 813 814 ProviderExecute(int code, Uri uri) { 815 this(code, uri, null); 816 } 817 818 static Uri opInsert(Uri uri, ContentValues values) { 819 ProviderExecute e = new ProviderExecute(INSERT, uri, values); 820 if (offUiThread()) return (Uri)e.go(); 821 new Thread(e).start(); 822 return null; 823 } 824 825 static int opDelete(Uri uri) { 826 ProviderExecute e = new ProviderExecute(DELETE, uri); 827 if (offUiThread()) return (Integer)e.go(); 828 new Thread(new ProviderExecute(DELETE, uri)).start(); 829 return 0; 830 } 831 832 static int opUpdate(Uri uri, ContentValues values) { 833 ProviderExecute e = new ProviderExecute(UPDATE, uri, values); 834 if (offUiThread()) return (Integer)e.go(); 835 new Thread(e).start(); 836 return 0; 837 } 838 839 @Override 840 public void run() { 841 go(); 842 } 843 844 public Object go() { 845 switch(mCode) { 846 case DELETE: 847 return mResolver.delete(mUri, null, null); 848 case INSERT: 849 return mResolver.insert(mUri, mValues); 850 case UPDATE: 851 return mResolver.update(mUri, mValues, null, null); 852 default: 853 return null; 854 } 855 } 856 } 857 858 private void insertLocal(Uri uri, ContentValues values) { 859 // Placeholder for now; there's no local insert 860 } 861 862 @VisibleForTesting 863 void deleteLocal(Uri uri) { 864 Uri underlyingUri = uriFromCachingUri(uri); 865 // Remember to decode the underlying Uri as it might be encoded (as w/ Gmail) 866 String uriString = Uri.decode(underlyingUri.toString()); 867 cacheValue(uriString, DELETED_COLUMN, true); 868 } 869 870 @VisibleForTesting 871 void updateLocal(Uri uri, ContentValues values) { 872 if (values == null) { 873 return; 874 } 875 Uri underlyingUri = uriFromCachingUri(uri); 876 // Remember to decode the underlying Uri as it might be encoded (as w/ Gmail) 877 String uriString = Uri.decode(underlyingUri.toString()); 878 for (String columnName: values.keySet()) { 879 cacheValue(uriString, columnName, values.get(columnName)); 880 } 881 } 882 883 static boolean offUiThread() { 884 return Looper.getMainLooper().getThread() != Thread.currentThread(); 885 } 886 887 public int apply(ArrayList<ConversationOperation> ops) { 888 final HashMap<String, ArrayList<ContentProviderOperation>> batchMap = 889 new HashMap<String, ArrayList<ContentProviderOperation>>(); 890 // Increment sequence count 891 sSequence++; 892 // Execute locally and build CPO's for underlying provider 893 for (ConversationOperation op: ops) { 894 Uri underlyingUri = uriFromCachingUri(op.mUri); 895 String authority = underlyingUri.getAuthority(); 896 ArrayList<ContentProviderOperation> authOps = batchMap.get(authority); 897 if (authOps == null) { 898 authOps = new ArrayList<ContentProviderOperation>(); 899 batchMap.put(authority, authOps); 900 } 901 authOps.add(op.execute(underlyingUri)); 902 } 903 904 // Send changes to underlying provider 905 for (String authority: batchMap.keySet()) { 906 try { 907 if (offUiThread()) { 908 mResolver.applyBatch(authority, batchMap.get(authority)); 909 } else { 910 final String auth = authority; 911 new Thread(new Runnable() { 912 @Override 913 public void run() { 914 try { 915 mResolver.applyBatch(auth, batchMap.get(auth)); 916 } catch (RemoteException e) { 917 } catch (OperationApplicationException e) { 918 } 919 } 920 }).start(); 921 } 922 } catch (RemoteException e) { 923 } catch (OperationApplicationException e) { 924 } 925 } 926 return sSequence; 927 } 928 } 929 930 /** 931 * ConversationOperation is the encapsulation of a ContentProvider operation to be performed 932 * atomically as part of a "batch" operation. 933 */ 934 public static class ConversationOperation { 935 public static final int DELETE = 0; 936 public static final int INSERT = 1; 937 public static final int UPDATE = 2; 938 public static final int ARCHIVE = 3; 939 public static final int MUTE = 4; 940 public static final int REPORT_SPAM = 5; 941 942 private final int mType; 943 private final Uri mUri; 944 private final ContentValues mValues; 945 // True if an updated item should be removed locally (from ConversationCursor) 946 // This would be the case for a folder/label change in which the conversation is no longer 947 // in the folder represented by the ConversationCursor 948 private final boolean mLocalDeleteOnUpdate; 949 950 public ConversationOperation(int type, Conversation conv) { 951 this(type, conv, null); 952 } 953 954 public ConversationOperation(int type, Conversation conv, ContentValues values) { 955 mType = type; 956 mUri = conv.uri; 957 mValues = values; 958 mLocalDeleteOnUpdate = conv.localDeleteOnUpdate; 959 } 960 961 private ContentProviderOperation execute(Uri underlyingUri) { 962 Uri uri = underlyingUri.buildUpon() 963 .appendQueryParameter(UIProvider.SEQUENCE_QUERY_PARAMETER, 964 Integer.toString(sSequence)) 965 .build(); 966 switch(mType) { 967 case DELETE: 968 sProvider.deleteLocal(mUri); 969 return ContentProviderOperation.newDelete(uri).build(); 970 case UPDATE: 971 if (mLocalDeleteOnUpdate) { 972 sProvider.deleteLocal(mUri); 973 } else { 974 sProvider.updateLocal(mUri, mValues); 975 } 976 return ContentProviderOperation.newUpdate(uri) 977 .withValues(mValues) 978 .build(); 979 case INSERT: 980 sProvider.insertLocal(mUri, mValues); 981 return ContentProviderOperation.newInsert(uri) 982 .withValues(mValues).build(); 983 case ARCHIVE: 984 sProvider.deleteLocal(mUri); 985 986 // Create an update operation that represents archive 987 return ContentProviderOperation.newUpdate(uri).withValue( 988 ConversationOperations.OPERATION_KEY, ConversationOperations.ARCHIVE) 989 .build(); 990 case MUTE: 991 if (mLocalDeleteOnUpdate) { 992 sProvider.deleteLocal(mUri); 993 } 994 995 // Create an update operation that represents mute 996 return ContentProviderOperation.newUpdate(uri).withValue( 997 ConversationOperations.OPERATION_KEY, ConversationOperations.MUTE) 998 .build(); 999 case REPORT_SPAM: 1000 sProvider.deleteLocal(mUri); 1001 1002 // Create an update operation that represents report spam 1003 return ContentProviderOperation.newUpdate(uri).withValue( 1004 ConversationOperations.OPERATION_KEY, 1005 ConversationOperations.REPORT_SPAM).build(); 1006 default: 1007 throw new UnsupportedOperationException( 1008 "No such ConversationOperation type: " + mType); 1009 } 1010 } 1011 } 1012 1013 /** 1014 * For now, a single listener can be associated with the cursor, and for now we'll just 1015 * notify on deletions 1016 */ 1017 public interface ConversationListener { 1018 // Data in the underlying provider has changed; a refresh is required to sync up 1019 public void onRefreshRequired(); 1020 // We've completed a requested refresh of the underlying cursor 1021 public void onRefreshReady(); 1022 } 1023 1024 @Override 1025 public boolean isFirst() { 1026 throw new UnsupportedOperationException(); 1027 } 1028 1029 @Override 1030 public boolean isLast() { 1031 throw new UnsupportedOperationException(); 1032 } 1033 1034 @Override 1035 public boolean isBeforeFirst() { 1036 throw new UnsupportedOperationException(); 1037 } 1038 1039 @Override 1040 public boolean isAfterLast() { 1041 throw new UnsupportedOperationException(); 1042 } 1043 1044 @Override 1045 public int getColumnIndex(String columnName) { 1046 return sUnderlyingCursor.getColumnIndex(columnName); 1047 } 1048 1049 @Override 1050 public int getColumnIndexOrThrow(String columnName) throws IllegalArgumentException { 1051 return sUnderlyingCursor.getColumnIndexOrThrow(columnName); 1052 } 1053 1054 @Override 1055 public String getColumnName(int columnIndex) { 1056 return sUnderlyingCursor.getColumnName(columnIndex); 1057 } 1058 1059 @Override 1060 public String[] getColumnNames() { 1061 return sUnderlyingCursor.getColumnNames(); 1062 } 1063 1064 @Override 1065 public int getColumnCount() { 1066 return sUnderlyingCursor.getColumnCount(); 1067 } 1068 1069 @Override 1070 public void copyStringToBuffer(int columnIndex, CharArrayBuffer buffer) { 1071 throw new UnsupportedOperationException(); 1072 } 1073 1074 @Override 1075 public int getType(int columnIndex) { 1076 return sUnderlyingCursor.getType(columnIndex); 1077 } 1078 1079 @Override 1080 public boolean isNull(int columnIndex) { 1081 throw new UnsupportedOperationException(); 1082 } 1083 1084 @Override 1085 public void deactivate() { 1086 throw new UnsupportedOperationException(); 1087 } 1088 1089 @Override 1090 public boolean isClosed() { 1091 return sUnderlyingCursor.isClosed(); 1092 } 1093 1094 @Override 1095 public void registerContentObserver(ContentObserver observer) { 1096 sUnderlyingCursor.registerContentObserver(observer); 1097 } 1098 1099 @Override 1100 public void unregisterContentObserver(ContentObserver observer) { 1101 sUnderlyingCursor.unregisterContentObserver(observer); 1102 } 1103 1104 @Override 1105 public void registerDataSetObserver(DataSetObserver observer) { 1106 sUnderlyingCursor.registerDataSetObserver(observer); 1107 } 1108 1109 @Override 1110 public void unregisterDataSetObserver(DataSetObserver observer) { 1111 sUnderlyingCursor.unregisterDataSetObserver(observer); 1112 } 1113 1114 @Override 1115 public void setNotificationUri(ContentResolver cr, Uri uri) { 1116 throw new UnsupportedOperationException(); 1117 } 1118 1119 @Override 1120 public boolean getWantsAllOnMoveCalls() { 1121 throw new UnsupportedOperationException(); 1122 } 1123 1124 @Override 1125 public Bundle getExtras() { 1126 throw new UnsupportedOperationException(); 1127 } 1128 1129 @Override 1130 public Bundle respond(Bundle extras) { 1131 throw new UnsupportedOperationException(); 1132 } 1133 1134 @Override 1135 public boolean requery() { 1136 return true; 1137 } 1138} 1139