/**
* Delete all messages (optionally for a specific client)
*
* @param clientHandle identifier for the client.<br>
* If null, all messages are deleted
*/
@Override
public void clearArrivedMessages(String clientHandle) {
db = mqttDb.getWritableDatabase();
int rows = 0;
if (clientHandle == null) {
traceHandler.traceDebug(TAG, "clearArrivedMessages: clearing the table");
rows = db.delete(ARRIVED_MESSAGE_TABLE_NAME, null, null);
} else {
traceHandler.traceDebug(
TAG, "clearArrivedMessages: clearing the table of " + clientHandle + " messages");
rows =
db.delete(
ARRIVED_MESSAGE_TABLE_NAME,
MqttServiceConstants.CLIENT_HANDLE + "='" + clientHandle + "'",
null);
}
traceHandler.traceDebug(TAG, "clearArrivedMessages: rows affected = " + rows);
return;
}
/**
* Delete an MQTT message.
*
* @param clientHandle identifier for the client which stored the message
* @param id the identifying string returned when the message was stored
* @return true if the message was found and deleted
*/
@Override
public boolean discardArrived(String clientHandle, String id) {
db = mqttDb.getWritableDatabase();
traceHandler.traceDebug(TAG, "discardArrived{" + clientHandle + "}, {" + id + "}");
int rows;
try {
rows =
db.delete(
ARRIVED_MESSAGE_TABLE_NAME,
MqttServiceConstants.MESSAGE_ID
+ "='"
+ id
+ "' AND "
+ MqttServiceConstants.CLIENT_HANDLE
+ "='"
+ clientHandle
+ "'",
null);
} catch (SQLException e) {
traceHandler.traceException(TAG, "discardArrived", e);
throw e;
}
if (rows != 1) {
traceHandler.traceError(
TAG,
"discardArrived - Error deleting message {"
+ id
+ "} from database: Rows affected = "
+ rows);
return false;
}
int count = getArrivedRowCount(clientHandle);
traceHandler.traceDebug(
TAG,
"discardArrived - Message deleted successfully. - messages in db for this clientHandle "
+ count);
return true;
}
/**
* Store an MQTT message
*
* @param clientHandle identifier for the client storing the message
* @param topic The topic on which the message was published
* @param message the arrived MQTT message
* @return an identifier for the message, so that it can be removed when appropriate
*/
@Override
public String storeArrived(String clientHandle, String topic, MqttMessage message) {
db = mqttDb.getWritableDatabase();
traceHandler.traceDebug(
TAG, "storeArrived{" + clientHandle + "}, {" + message.toString() + "}");
byte[] payload = message.getPayload();
int qos = message.getQos();
boolean retained = message.isRetained();
boolean duplicate = message.isDuplicate();
ContentValues values = new ContentValues();
String id = java.util.UUID.randomUUID().toString();
values.put(MqttServiceConstants.MESSAGE_ID, id);
values.put(MqttServiceConstants.CLIENT_HANDLE, clientHandle);
values.put(MqttServiceConstants.DESTINATION_NAME, topic);
values.put(MqttServiceConstants.PAYLOAD, payload);
values.put(MqttServiceConstants.QOS, qos);
values.put(MqttServiceConstants.RETAINED, retained);
values.put(MqttServiceConstants.DUPLICATE, duplicate);
values.put(MTIMESTAMP, System.currentTimeMillis());
try {
db.insertOrThrow(ARRIVED_MESSAGE_TABLE_NAME, null, values);
} catch (SQLException e) {
traceHandler.traceException(TAG, "onUpgrade", e);
throw e;
}
int count = getArrivedRowCount(clientHandle);
traceHandler.traceDebug(
TAG,
"storeArrived: inserted message with id of {"
+ id
+ "} - Number of messages in database for this clientHandle = "
+ count);
return id;
}
