/**
* Add the event to the end of queue.
*
* @param event The event to add to the queue.
* @exception FrameworkException Thrown on errors.
*/
public void add(Event event) throws FrameworkException {
Debug.log(Debug.MSG_STATUS, "QUEUE OPERATION: Adding event to database queue ...");
Connection dbConn = null;
PreparedStatement ps = null;
long startTime = -1;
if (Debug.isLevelEnabled(Debug.BENCHMARK)) startTime = System.currentTimeMillis();
try {
event.id = PersistentSequence.getNextSequenceValue(SEQUENCE_NAME);
dbConn = DBConnectionPool.getInstance().acquireConnection();
event.arrivalTime = new java.sql.Timestamp(System.currentTimeMillis());
if (Debug.isLevelEnabled(Debug.DB_DATA))
Debug.log(Debug.DB_DATA, "\n" + LINE + "\nExecuting SQL:\n" + INSERT_EVENT_SQL);
if (Debug.isLevelEnabled(Debug.DB_DATA))
Debug.log(Debug.DB_DATA, "Event being inserted into database:\n" + event.describe());
if (Debug.isLevelEnabled(Debug.MSG_DATA))
Debug.log(Debug.MSG_DATA, "Event contents:\n" + event.message);
ps = dbConn.prepareStatement(INSERT_EVENT_SQL);
ps.setString(1, event.channelName);
ps.setInt(2, event.id);
DBLOBUtils.setCLOB(ps, 3, event.message);
ps.setTimestamp(4, event.arrivalTime);
int numRows = ps.executeUpdate();
if (numRows != 1) {
String errMsg =
"Execution of SQL statement ["
+ INSERT_EVENT_SQL
+ "] affected ["
+ numRows
+ "] rows.";
Debug.error(errMsg);
throw new FrameworkException(errMsg);
}
DBConnectionPool.getInstance().commit(dbConn);
if (Debug.isLevelEnabled(Debug.DB_DATA))
Debug.log(Debug.DB_DATA, "Successfully committed SQL operation.\n" + LINE);
// NOTE: We don't add the item just inserted into the database into the in-memory
// queue, as we want it loaded by the separate dequeueing thread.
} catch (SQLException sqle) {
throw new DatabaseException(
"ERROR: Could not execute SQL statement:\n" + DBInterface.getSQLErrorMessage(sqle));
} catch (Exception e) {
throw new DatabaseException("ERROR: Could not execute SQL statement:\n" + e.toString());
} finally {
releaseDatabaseResources(dbConn, ps);
if (Debug.isLevelEnabled(Debug.BENCHMARK) && (startTime > 0)) {
long stopTime = System.currentTimeMillis();
Debug.log(
Debug.BENCHMARK,
"ELAPSED TIME ["
+ (stopTime - startTime)
+ "] msec: "
+ "SQL: Time to insert event into PersistentEvent database table.");
}
}
}
/**
* Update the given event as indicated.
*
* @param event The event to update.
* @param eventStatus The event delivery status.
* @exception FrameworkException Thrown on errors.
*/
public void update(Event event, EventStatus eventStatus) throws FrameworkException {
if (Debug.isLevelEnabled(Debug.MSG_STATUS))
Debug.log(
Debug.MSG_STATUS,
"QUEUE OPERATION: Updating database queue using event status ["
+ eventStatus.name
+ "] ...");
// If no consumers were available, the event delivery wasn't attempted so leave
// the queue in its current state.
if (eventStatus == EventStatus.NO_CONSUMERS_AVAILABLE) {
Debug.log(
Debug.MSG_STATUS, "Skipping queue update, as no consumers were available to process it.");
return;
}
Connection dbConn = null;
PreparedStatement ps = null;
long startTime = -1;
if (Debug.isLevelEnabled(Debug.BENCHMARK)) startTime = System.currentTimeMillis();
try {
dbConn = DBConnectionPool.getInstance().acquireConnection();
if (eventStatus == EventStatus.DELIVERY_SUCCESSFUL) {
// If the event was successfully delivered, update status in database to delivered.
if (Debug.isLevelEnabled(Debug.DB_DATA))
Debug.log(Debug.DB_DATA, "\n" + LINE + "\nExecuting SQL:\n" + UPDATE_EVENT_SUCCESS_SQL);
ps = dbConn.prepareStatement(UPDATE_EVENT_SUCCESS_SQL);
java.sql.Timestamp ts = new java.sql.Timestamp(System.currentTimeMillis());
ps.setTimestamp(1, ts);
ps.setString(2, event.channelName);
ps.setInt(3, event.id);
} else if (eventStatus == EventStatus.DELIVERY_FAILED) {
// If the event delivery failed, we mark it as failed in the database.
if (Debug.isLevelEnabled(Debug.DB_DATA))
Debug.log(Debug.DB_DATA, "\n" + LINE + "\nExecuting SQL:\n" + UPDATE_EVENT_ERROR_SQL);
// Truncate error message if it's larger than database column.
if ((event.lastErrorMessage != null)
&& (event.lastErrorMessage.length() > MAX_ERROR_MESSAGE_LENGTH))
event.lastErrorMessage = event.lastErrorMessage.substring(0, MAX_ERROR_MESSAGE_LENGTH);
event.lastErrorTime = new java.sql.Timestamp(System.currentTimeMillis());
ps = dbConn.prepareStatement(UPDATE_EVENT_ERROR_SQL);
ps.setTimestamp(1, event.lastErrorTime);
ps.setString(2, event.lastErrorMessage);
ps.setString(3, event.channelName);
ps.setInt(4, event.id);
} else {
throw new FrameworkException(
"ERROR: Invalid event update type [" + eventStatus.name + "].");
}
if (Debug.isLevelEnabled(Debug.DB_DATA))
Debug.log(Debug.DB_DATA, "Event being operated on in database:\n" + event.describe());
int numRows = ps.executeUpdate();
if (numRows > 1) {
String errMsg = "Execution of update SQL statement affected [" + numRows + "] rows.";
Debug.error(errMsg);
throw new FrameworkException(errMsg);
}
DBConnectionPool.getInstance().commit(dbConn);
if (Debug.isLevelEnabled(Debug.DB_DATA))
Debug.log(Debug.DB_DATA, "Successfully committed SQL operation.\n" + LINE);
// At this point, the event should be removed from the in-memory buffer of events as well,
// irrespective of processing outcome.
if (Debug.isLevelEnabled(Debug.MSG_STATUS))
Debug.log(
Debug.MSG_STATUS,
"Removing event [" + event.describe() + "] from in-memory queue buffer.");
boolean removed = queue.remove(event);
if (Debug.isLevelEnabled(Debug.MSG_STATUS))
Debug.log(
Debug.MSG_STATUS,
"Event removed? ["
+ removed
+ "]. In-memory queue buffer size ["
+ queue.size()
+ "].");
} catch (SQLException sqle) {
throw new DatabaseException(
"ERROR: Could not execute SQL statement:\n" + DBInterface.getSQLErrorMessage(sqle));
} catch (Exception e) {
throw new DatabaseException("ERROR: Could not execute SQL statement:\n" + e.toString());
} finally {
releaseDatabaseResources(dbConn, ps);
if (Debug.isLevelEnabled(Debug.BENCHMARK) && (startTime > 0)) {
long stopTime = System.currentTimeMillis();
Debug.log(
Debug.BENCHMARK,
"ELAPSED TIME ["
+ (stopTime - startTime)
+ "] msec: "
+ "SQL: Time to update event in PersistentEvent database table.");
}
}
}
