| /* |
| * Copyright (C) 2007 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 com.android.providers.settings; |
| |
| import java.io.FileNotFoundException; |
| import java.io.UnsupportedEncodingException; |
| import java.security.NoSuchAlgorithmException; |
| import java.security.SecureRandom; |
| import java.util.LinkedHashMap; |
| import java.util.Map; |
| |
| import android.app.backup.BackupManager; |
| import android.content.ContentProvider; |
| import android.content.ContentUris; |
| import android.content.ContentValues; |
| import android.content.Context; |
| import android.content.pm.PackageManager; |
| import android.content.res.AssetFileDescriptor; |
| import android.database.Cursor; |
| import android.database.sqlite.SQLiteDatabase; |
| import android.database.sqlite.SQLiteException; |
| import android.database.sqlite.SQLiteQueryBuilder; |
| import android.media.RingtoneManager; |
| import android.net.Uri; |
| import android.os.Bundle; |
| import android.os.ParcelFileDescriptor; |
| import android.os.SystemProperties; |
| import android.provider.DrmStore; |
| import android.provider.MediaStore; |
| import android.provider.Settings; |
| import android.text.TextUtils; |
| import android.util.Log; |
| |
| public class SettingsProvider extends ContentProvider { |
| private static final String TAG = "SettingsProvider"; |
| private static final boolean LOCAL_LOGV = false; |
| |
| private static final String TABLE_FAVORITES = "favorites"; |
| private static final String TABLE_OLD_FAVORITES = "old_favorites"; |
| |
| private static final String[] COLUMN_VALUE = new String[] { "value" }; |
| |
| // Cache for settings, access-ordered for acting as LRU. |
| // Guarded by themselves. |
| private static final int MAX_CACHE_ENTRIES = 50; |
| private static final SettingsCache sSystemCache = new SettingsCache(); |
| private static final SettingsCache sSecureCache = new SettingsCache(); |
| |
| // Over this size we don't reject loading or saving settings but |
| // we do consider them broken/malicious and don't keep them in |
| // memory at least: |
| private static final int MAX_CACHE_ENTRY_SIZE = 500; |
| |
| private static final Bundle NULL_SETTING = Bundle.forPair("value", null); |
| |
| protected DatabaseHelper mOpenHelper; |
| private BackupManager mBackupManager; |
| |
| /** |
| * Decode a content URL into the table, projection, and arguments |
| * used to access the corresponding database rows. |
| */ |
| private static class SqlArguments { |
| public String table; |
| public final String where; |
| public final String[] args; |
| |
| /** Operate on existing rows. */ |
| SqlArguments(Uri url, String where, String[] args) { |
| if (url.getPathSegments().size() == 1) { |
| this.table = url.getPathSegments().get(0); |
| this.where = where; |
| this.args = args; |
| } else if (url.getPathSegments().size() != 2) { |
| throw new IllegalArgumentException("Invalid URI: " + url); |
| } else if (!TextUtils.isEmpty(where)) { |
| throw new UnsupportedOperationException("WHERE clause not supported: " + url); |
| } else { |
| this.table = url.getPathSegments().get(0); |
| if ("system".equals(this.table) || "secure".equals(this.table)) { |
| this.where = Settings.NameValueTable.NAME + "=?"; |
| this.args = new String[] { url.getPathSegments().get(1) }; |
| } else { |
| this.where = "_id=" + ContentUris.parseId(url); |
| this.args = null; |
| } |
| } |
| } |
| |
| /** Insert new rows (no where clause allowed). */ |
| SqlArguments(Uri url) { |
| if (url.getPathSegments().size() == 1) { |
| this.table = url.getPathSegments().get(0); |
| this.where = null; |
| this.args = null; |
| } else { |
| throw new IllegalArgumentException("Invalid URI: " + url); |
| } |
| } |
| } |
| |
| /** |
| * Get the content URI of a row added to a table. |
| * @param tableUri of the entire table |
| * @param values found in the row |
| * @param rowId of the row |
| * @return the content URI for this particular row |
| */ |
| private Uri getUriFor(Uri tableUri, ContentValues values, long rowId) { |
| if (tableUri.getPathSegments().size() != 1) { |
| throw new IllegalArgumentException("Invalid URI: " + tableUri); |
| } |
| String table = tableUri.getPathSegments().get(0); |
| if ("system".equals(table) || "secure".equals(table)) { |
| String name = values.getAsString(Settings.NameValueTable.NAME); |
| return Uri.withAppendedPath(tableUri, name); |
| } else { |
| return ContentUris.withAppendedId(tableUri, rowId); |
| } |
| } |
| |
| /** |
| * Send a notification when a particular content URI changes. |
| * Modify the system property used to communicate the version of |
| * this table, for tables which have such a property. (The Settings |
| * contract class uses these to provide client-side caches.) |
| * @param uri to send notifications for |
| */ |
| private void sendNotify(Uri uri) { |
| // Update the system property *first*, so if someone is listening for |
| // a notification and then using the contract class to get their data, |
| // the system property will be updated and they'll get the new data. |
| |
| boolean backedUpDataChanged = false; |
| String property = null, table = uri.getPathSegments().get(0); |
| if (table.equals("system")) { |
| property = Settings.System.SYS_PROP_SETTING_VERSION; |
| backedUpDataChanged = true; |
| } else if (table.equals("secure")) { |
| property = Settings.Secure.SYS_PROP_SETTING_VERSION; |
| backedUpDataChanged = true; |
| } |
| |
| if (property != null) { |
| long version = SystemProperties.getLong(property, 0) + 1; |
| if (LOCAL_LOGV) Log.v(TAG, "property: " + property + "=" + version); |
| SystemProperties.set(property, Long.toString(version)); |
| } |
| |
| // Inform the backup manager about a data change |
| if (backedUpDataChanged) { |
| mBackupManager.dataChanged(); |
| } |
| // Now send the notification through the content framework. |
| |
| String notify = uri.getQueryParameter("notify"); |
| if (notify == null || "true".equals(notify)) { |
| getContext().getContentResolver().notifyChange(uri, null); |
| if (LOCAL_LOGV) Log.v(TAG, "notifying: " + uri); |
| } else { |
| if (LOCAL_LOGV) Log.v(TAG, "notification suppressed: " + uri); |
| } |
| } |
| |
| /** |
| * Make sure the caller has permission to write this data. |
| * @param args supplied by the caller |
| * @throws SecurityException if the caller is forbidden to write. |
| */ |
| private void checkWritePermissions(SqlArguments args) { |
| if ("secure".equals(args.table) && |
| getContext().checkCallingOrSelfPermission( |
| android.Manifest.permission.WRITE_SECURE_SETTINGS) != |
| PackageManager.PERMISSION_GRANTED) { |
| throw new SecurityException( |
| String.format("Permission denial: writing to secure settings requires %1$s", |
| android.Manifest.permission.WRITE_SECURE_SETTINGS)); |
| } |
| } |
| |
| @Override |
| public boolean onCreate() { |
| mOpenHelper = new DatabaseHelper(getContext()); |
| mBackupManager = new BackupManager(getContext()); |
| |
| if (!ensureAndroidIdIsSet()) { |
| return false; |
| } |
| |
| return true; |
| } |
| |
| private boolean ensureAndroidIdIsSet() { |
| final Cursor c = query(Settings.Secure.CONTENT_URI, |
| new String[] { Settings.NameValueTable.VALUE }, |
| Settings.NameValueTable.NAME + "=?", |
| new String[] { Settings.Secure.ANDROID_ID }, null); |
| try { |
| final String value = c.moveToNext() ? c.getString(0) : null; |
| if (value == null) { |
| final SecureRandom random = SecureRandom.getInstance("SHA1PRNG"); |
| String serial = SystemProperties.get("ro.serialno"); |
| if (serial != null) { |
| try { |
| random.setSeed(serial.getBytes("UTF-8")); |
| } catch (UnsupportedEncodingException ignore) { |
| // stick with default seed |
| } |
| } |
| final String newAndroidIdValue = Long.toHexString(random.nextLong()); |
| Log.d(TAG, "Generated and saved new ANDROID_ID"); |
| final ContentValues values = new ContentValues(); |
| values.put(Settings.NameValueTable.NAME, Settings.Secure.ANDROID_ID); |
| values.put(Settings.NameValueTable.VALUE, newAndroidIdValue); |
| final Uri uri = insert(Settings.Secure.CONTENT_URI, values); |
| if (uri == null) { |
| return false; |
| } |
| } |
| return true; |
| } catch (NoSuchAlgorithmException e) { |
| return false; |
| } finally { |
| c.close(); |
| } |
| } |
| |
| /** |
| * Fast path that avoids the use of chatty remoted Cursors. |
| */ |
| @Override |
| public Bundle call(String method, String request, Bundle args) { |
| if (Settings.CALL_METHOD_GET_SYSTEM.equals(method)) { |
| return lookupValue("system", sSystemCache, request); |
| } |
| if (Settings.CALL_METHOD_GET_SECURE.equals(method)) { |
| return lookupValue("secure", sSecureCache, request); |
| } |
| return null; |
| } |
| |
| // Looks up value 'key' in 'table' and returns either a single-pair Bundle, |
| // possibly with a null value, or null on failure. |
| private Bundle lookupValue(String table, SettingsCache cache, String key) { |
| synchronized (cache) { |
| if (cache.containsKey(key)) { |
| return cache.get(key); |
| } |
| } |
| |
| SQLiteDatabase db = mOpenHelper.getReadableDatabase(); |
| Cursor cursor = null; |
| try { |
| cursor = db.query(table, COLUMN_VALUE, "name=?", new String[]{key}, |
| null, null, null, null); |
| if (cursor != null && cursor.getCount() == 1) { |
| cursor.moveToFirst(); |
| return cache.putIfAbsent(key, cursor.getString(0)); |
| } |
| } catch (SQLiteException e) { |
| Log.w(TAG, "settings lookup error", e); |
| return null; |
| } finally { |
| if (cursor != null) cursor.close(); |
| } |
| cache.putIfAbsent(key, null); |
| return NULL_SETTING; |
| } |
| |
| @Override |
| public Cursor query(Uri url, String[] select, String where, String[] whereArgs, String sort) { |
| SqlArguments args = new SqlArguments(url, where, whereArgs); |
| SQLiteDatabase db = mOpenHelper.getReadableDatabase(); |
| |
| // The favorites table was moved from this provider to a provider inside Home |
| // Home still need to query this table to upgrade from pre-cupcake builds |
| // However, a cupcake+ build with no data does not contain this table which will |
| // cause an exception in the SQL stack. The following line is a special case to |
| // let the caller of the query have a chance to recover and avoid the exception |
| if (TABLE_FAVORITES.equals(args.table)) { |
| return null; |
| } else if (TABLE_OLD_FAVORITES.equals(args.table)) { |
| args.table = TABLE_FAVORITES; |
| Cursor cursor = db.rawQuery("PRAGMA table_info(favorites);", null); |
| if (cursor != null) { |
| boolean exists = cursor.getCount() > 0; |
| cursor.close(); |
| if (!exists) return null; |
| } else { |
| return null; |
| } |
| } |
| |
| SQLiteQueryBuilder qb = new SQLiteQueryBuilder(); |
| qb.setTables(args.table); |
| |
| Cursor ret = qb.query(db, select, args.where, args.args, null, null, sort); |
| ret.setNotificationUri(getContext().getContentResolver(), url); |
| return ret; |
| } |
| |
| @Override |
| public String getType(Uri url) { |
| // If SqlArguments supplies a where clause, then it must be an item |
| // (because we aren't supplying our own where clause). |
| SqlArguments args = new SqlArguments(url, null, null); |
| if (TextUtils.isEmpty(args.where)) { |
| return "vnd.android.cursor.dir/" + args.table; |
| } else { |
| return "vnd.android.cursor.item/" + args.table; |
| } |
| } |
| |
| @Override |
| public int bulkInsert(Uri uri, ContentValues[] values) { |
| SqlArguments args = new SqlArguments(uri); |
| if (TABLE_FAVORITES.equals(args.table)) { |
| return 0; |
| } |
| checkWritePermissions(args); |
| SettingsCache cache = SettingsCache.forTable(args.table); |
| |
| SQLiteDatabase db = mOpenHelper.getWritableDatabase(); |
| db.beginTransaction(); |
| try { |
| int numValues = values.length; |
| for (int i = 0; i < numValues; i++) { |
| if (db.insert(args.table, null, values[i]) < 0) return 0; |
| SettingsCache.populate(cache, values[i]); |
| if (LOCAL_LOGV) Log.v(TAG, args.table + " <- " + values[i]); |
| } |
| db.setTransactionSuccessful(); |
| } finally { |
| db.endTransaction(); |
| } |
| |
| sendNotify(uri); |
| return values.length; |
| } |
| |
| /* |
| * Used to parse changes to the value of Settings.Secure.LOCATION_PROVIDERS_ALLOWED. |
| * This setting contains a list of the currently enabled location providers. |
| * But helper functions in android.providers.Settings can enable or disable |
| * a single provider by using a "+" or "-" prefix before the provider name. |
| * |
| * @returns whether the database needs to be updated or not, also modifying |
| * 'initialValues' if needed. |
| */ |
| private boolean parseProviderList(Uri url, ContentValues initialValues) { |
| String value = initialValues.getAsString(Settings.Secure.VALUE); |
| String newProviders = null; |
| if (value != null && value.length() > 1) { |
| char prefix = value.charAt(0); |
| if (prefix == '+' || prefix == '-') { |
| // skip prefix |
| value = value.substring(1); |
| |
| // read list of enabled providers into "providers" |
| String providers = ""; |
| String[] columns = {Settings.Secure.VALUE}; |
| String where = Settings.Secure.NAME + "=\'" + Settings.Secure.LOCATION_PROVIDERS_ALLOWED + "\'"; |
| Cursor cursor = query(url, columns, where, null, null); |
| if (cursor != null && cursor.getCount() == 1) { |
| try { |
| cursor.moveToFirst(); |
| providers = cursor.getString(0); |
| } finally { |
| cursor.close(); |
| } |
| } |
| |
| int index = providers.indexOf(value); |
| int end = index + value.length(); |
| // check for commas to avoid matching on partial string |
| if (index > 0 && providers.charAt(index - 1) != ',') index = -1; |
| if (end < providers.length() && providers.charAt(end) != ',') index = -1; |
| |
| if (prefix == '+' && index < 0) { |
| // append the provider to the list if not present |
| if (providers.length() == 0) { |
| newProviders = value; |
| } else { |
| newProviders = providers + ',' + value; |
| } |
| } else if (prefix == '-' && index >= 0) { |
| // remove the provider from the list if present |
| // remove leading or trailing comma |
| if (index > 0) { |
| index--; |
| } else if (end < providers.length()) { |
| end++; |
| } |
| |
| newProviders = providers.substring(0, index); |
| if (end < providers.length()) { |
| newProviders += providers.substring(end); |
| } |
| } else { |
| // nothing changed, so no need to update the database |
| return false; |
| } |
| |
| if (newProviders != null) { |
| initialValues.put(Settings.Secure.VALUE, newProviders); |
| } |
| } |
| } |
| |
| return true; |
| } |
| |
| @Override |
| public Uri insert(Uri url, ContentValues initialValues) { |
| SqlArguments args = new SqlArguments(url); |
| if (TABLE_FAVORITES.equals(args.table)) { |
| return null; |
| } |
| checkWritePermissions(args); |
| |
| // Special case LOCATION_PROVIDERS_ALLOWED. |
| // Support enabling/disabling a single provider (using "+" or "-" prefix) |
| String name = initialValues.getAsString(Settings.Secure.NAME); |
| if (Settings.Secure.LOCATION_PROVIDERS_ALLOWED.equals(name)) { |
| if (!parseProviderList(url, initialValues)) return null; |
| } |
| |
| SettingsCache cache = SettingsCache.forTable(args.table); |
| String value = initialValues.getAsString(Settings.NameValueTable.VALUE); |
| if (SettingsCache.isRedundantSetValue(cache, name, value)) { |
| return Uri.withAppendedPath(url, name); |
| } |
| |
| SQLiteDatabase db = mOpenHelper.getWritableDatabase(); |
| final long rowId = db.insert(args.table, null, initialValues); |
| if (rowId <= 0) return null; |
| |
| SettingsCache.populate(cache, initialValues); // before we notify |
| |
| if (LOCAL_LOGV) Log.v(TAG, args.table + " <- " + initialValues); |
| url = getUriFor(url, initialValues, rowId); |
| sendNotify(url); |
| return url; |
| } |
| |
| @Override |
| public int delete(Uri url, String where, String[] whereArgs) { |
| SqlArguments args = new SqlArguments(url, where, whereArgs); |
| if (TABLE_FAVORITES.equals(args.table)) { |
| return 0; |
| } else if (TABLE_OLD_FAVORITES.equals(args.table)) { |
| args.table = TABLE_FAVORITES; |
| } |
| checkWritePermissions(args); |
| |
| SQLiteDatabase db = mOpenHelper.getWritableDatabase(); |
| int count = db.delete(args.table, args.where, args.args); |
| if (count > 0) { |
| SettingsCache.wipe(args.table); // before we notify |
| sendNotify(url); |
| } |
| if (LOCAL_LOGV) Log.v(TAG, args.table + ": " + count + " row(s) deleted"); |
| return count; |
| } |
| |
| @Override |
| public int update(Uri url, ContentValues initialValues, String where, String[] whereArgs) { |
| SqlArguments args = new SqlArguments(url, where, whereArgs); |
| if (TABLE_FAVORITES.equals(args.table)) { |
| return 0; |
| } |
| checkWritePermissions(args); |
| |
| SQLiteDatabase db = mOpenHelper.getWritableDatabase(); |
| int count = db.update(args.table, initialValues, args.where, args.args); |
| if (count > 0) { |
| SettingsCache.wipe(args.table); // before we notify |
| sendNotify(url); |
| } |
| if (LOCAL_LOGV) Log.v(TAG, args.table + ": " + count + " row(s) <- " + initialValues); |
| return count; |
| } |
| |
| @Override |
| public ParcelFileDescriptor openFile(Uri uri, String mode) throws FileNotFoundException { |
| |
| /* |
| * When a client attempts to openFile the default ringtone or |
| * notification setting Uri, we will proxy the call to the current |
| * default ringtone's Uri (if it is in the DRM or media provider). |
| */ |
| int ringtoneType = RingtoneManager.getDefaultType(uri); |
| // Above call returns -1 if the Uri doesn't match a default type |
| if (ringtoneType != -1) { |
| Context context = getContext(); |
| |
| // Get the current value for the default sound |
| Uri soundUri = RingtoneManager.getActualDefaultRingtoneUri(context, ringtoneType); |
| |
| if (soundUri != null) { |
| // Only proxy the openFile call to drm or media providers |
| String authority = soundUri.getAuthority(); |
| boolean isDrmAuthority = authority.equals(DrmStore.AUTHORITY); |
| if (isDrmAuthority || authority.equals(MediaStore.AUTHORITY)) { |
| |
| if (isDrmAuthority) { |
| try { |
| // Check DRM access permission here, since once we |
| // do the below call the DRM will be checking our |
| // permission, not our caller's permission |
| DrmStore.enforceAccessDrmPermission(context); |
| } catch (SecurityException e) { |
| throw new FileNotFoundException(e.getMessage()); |
| } |
| } |
| |
| return context.getContentResolver().openFileDescriptor(soundUri, mode); |
| } |
| } |
| } |
| |
| return super.openFile(uri, mode); |
| } |
| |
| @Override |
| public AssetFileDescriptor openAssetFile(Uri uri, String mode) throws FileNotFoundException { |
| |
| /* |
| * When a client attempts to openFile the default ringtone or |
| * notification setting Uri, we will proxy the call to the current |
| * default ringtone's Uri (if it is in the DRM or media provider). |
| */ |
| int ringtoneType = RingtoneManager.getDefaultType(uri); |
| // Above call returns -1 if the Uri doesn't match a default type |
| if (ringtoneType != -1) { |
| Context context = getContext(); |
| |
| // Get the current value for the default sound |
| Uri soundUri = RingtoneManager.getActualDefaultRingtoneUri(context, ringtoneType); |
| |
| if (soundUri != null) { |
| // Only proxy the openFile call to drm or media providers |
| String authority = soundUri.getAuthority(); |
| boolean isDrmAuthority = authority.equals(DrmStore.AUTHORITY); |
| if (isDrmAuthority || authority.equals(MediaStore.AUTHORITY)) { |
| |
| if (isDrmAuthority) { |
| try { |
| // Check DRM access permission here, since once we |
| // do the below call the DRM will be checking our |
| // permission, not our caller's permission |
| DrmStore.enforceAccessDrmPermission(context); |
| } catch (SecurityException e) { |
| throw new FileNotFoundException(e.getMessage()); |
| } |
| } |
| |
| ParcelFileDescriptor pfd = null; |
| try { |
| pfd = context.getContentResolver().openFileDescriptor(soundUri, mode); |
| return new AssetFileDescriptor(pfd, 0, -1); |
| } catch (FileNotFoundException ex) { |
| // fall through and open the fallback ringtone below |
| } |
| } |
| |
| try { |
| return super.openAssetFile(soundUri, mode); |
| } catch (FileNotFoundException ex) { |
| // Since a non-null Uri was specified, but couldn't be opened, |
| // fall back to the built-in ringtone. |
| return context.getResources().openRawResourceFd( |
| com.android.internal.R.raw.fallbackring); |
| } |
| } |
| // no need to fall through and have openFile() try again, since we |
| // already know that will fail. |
| throw new FileNotFoundException(); // or return null ? |
| } |
| |
| // Note that this will end up calling openFile() above. |
| return super.openAssetFile(uri, mode); |
| } |
| |
| /** |
| * In-memory LRU Cache of system and secure settings, along with |
| * associated helper functions to keep cache coherent with the |
| * database. |
| */ |
| private static final class SettingsCache extends LinkedHashMap<String, Bundle> { |
| |
| public SettingsCache() { |
| super(MAX_CACHE_ENTRIES, 0.75f /* load factor */, true /* access ordered */); |
| } |
| |
| @Override |
| protected boolean removeEldestEntry(Map.Entry eldest) { |
| return size() > MAX_CACHE_ENTRIES; |
| } |
| |
| /** |
| * Atomic cache population, conditional on size of value and if |
| * we lost a race. |
| * |
| * @returns a Bundle to send back to the client from call(), even |
| * if we lost the race. |
| */ |
| public Bundle putIfAbsent(String key, String value) { |
| Bundle bundle = (value == null) ? NULL_SETTING : Bundle.forPair("value", value); |
| if (value == null || value.length() <= MAX_CACHE_ENTRY_SIZE) { |
| synchronized (this) { |
| if (!containsKey(key)) { |
| put(key, bundle); |
| } |
| } |
| } |
| return bundle; |
| } |
| |
| public static SettingsCache forTable(String tableName) { |
| if ("system".equals(tableName)) { |
| return SettingsProvider.sSystemCache; |
| } |
| if ("secure".equals(tableName)) { |
| return SettingsProvider.sSecureCache; |
| } |
| return null; |
| } |
| |
| /** |
| * Populates a key in a given (possibly-null) cache. |
| */ |
| public static void populate(SettingsCache cache, ContentValues contentValues) { |
| if (cache == null) { |
| return; |
| } |
| String name = contentValues.getAsString(Settings.NameValueTable.NAME); |
| if (name == null) { |
| Log.w(TAG, "null name populating settings cache."); |
| return; |
| } |
| String value = contentValues.getAsString(Settings.NameValueTable.VALUE); |
| synchronized (cache) { |
| if (value == null || value.length() <= MAX_CACHE_ENTRY_SIZE) { |
| cache.put(name, Bundle.forPair(Settings.NameValueTable.VALUE, value)); |
| } else { |
| cache.remove(name); |
| } |
| } |
| } |
| |
| /** |
| * Used for wiping a whole cache on deletes when we're not |
| * sure what exactly was deleted or changed. |
| */ |
| public static void wipe(String tableName) { |
| SettingsCache cache = SettingsCache.forTable(tableName); |
| if (cache == null) { |
| return; |
| } |
| synchronized (cache) { |
| cache.clear(); |
| } |
| } |
| |
| /** |
| * For suppressing duplicate/redundant settings inserts early, |
| * checking our cache first (but without faulting it in), |
| * before going to sqlite with the mutation. |
| */ |
| public static boolean isRedundantSetValue(SettingsCache cache, String name, String value) { |
| if (cache == null) return false; |
| synchronized (cache) { |
| Bundle bundle = cache.get(name); |
| if (bundle == null) return false; |
| String oldValue = bundle.getPairValue(); |
| if (oldValue == null && value == null) return true; |
| if ((oldValue == null) != (value == null)) return false; |
| return oldValue.equals(value); |
| } |
| } |
| } |
| } |