private static void prepareWAL(final SQLiteBridge bridge) {
// Prepare for WAL mode. If we can, we switch to journal_mode=WAL, then
// set the checkpoint size appropriately. If we can't, then we fall back
// to truncating and synchronous writes.
final Cursor cursor = bridge.internalQuery("PRAGMA journal_mode=WAL", null);
try {
if (cursor.moveToFirst()) {
String journalMode = cursor.getString(0);
Log.d(LOGTAG, "Journal mode: " + journalMode);
if ("wal".equals(journalMode)) {
// Success! Let's make sure we autocheckpoint at a reasonable interval.
final int pageSizeBytes = bridge.getPageSizeBytes();
final int checkpointPageCount = MAX_WAL_SIZE_BYTES / pageSizeBytes;
bridge.internalQuery("PRAGMA wal_autocheckpoint=" + checkpointPageCount, null).close();
} else {
if (!"truncate".equals(journalMode)) {
Log.w(LOGTAG, "Unable to activate WAL journal mode. Using truncate instead.");
bridge.internalQuery("PRAGMA journal_mode=TRUNCATE", null).close();
}
Log.w(LOGTAG, "Not using WAL mode: using synchronous=FULL instead.");
bridge.internalQuery("PRAGMA synchronous=FULL", null).close();
}
}
} finally {
cursor.close();
}
}
/*
* The second two parameters here are just provided for compatbility with SQLiteDatabase
* Support for them is not currently implemented
*/
public static SQLiteBridge openDatabase(
String path, SQLiteDatabase.CursorFactory factory, int flags) throws SQLiteException {
SQLiteBridge bridge = null;
try {
bridge = new SQLiteBridge(path);
bridge.mDbPointer = SQLiteBridge.openDatabase(path);
} catch (SQLiteBridgeException ex) {
// catch and rethrow as a SQLiteException to match SQLiteDatabase
throw new SQLiteException(ex.getMessage());
}
return bridge;
}
/*
* The second two parameters here are just provided for compatibility with SQLiteDatabase
* Support for them is not currently implemented.
*/
public static SQLiteBridge openDatabase(
String path, SQLiteDatabase.CursorFactory factory, int flags) throws SQLiteException {
if (factory != null) {
throw new RuntimeException("factory not supported.");
}
if (flags != 0) {
throw new RuntimeException("flags not supported.");
}
SQLiteBridge bridge = null;
try {
bridge = new SQLiteBridge(path);
bridge.mDbPointer = SQLiteBridge.openDatabase(path);
} catch (SQLiteBridgeException ex) {
// Catch and rethrow as a SQLiteException to match SQLiteDatabase.
throw new SQLiteException(ex.getMessage());
}
prepareWAL(bridge);
return bridge;
}
