public boolean contains(DeliverySystem delivery) {
synchronized (listeners) {
for (DistributionRequest listener : listeners)
if (listener.getDeliverySystem().equals(delivery)) return true;
return false;
}
}
private DataEnumerator makeDataEnum(DistributionRequest listener) {
PreparedStatement prepareStatement = preparedStatements.get(listener);
try {
// prepareStatement.setLong(1, listener.getStartTime());
prepareStatement.setLong(1, listener.getLastVisitedPk());
} catch (SQLException e) {
logger.error(e.getMessage(), e);
return new DataEnumerator();
}
DataEnumerator dataEnum =
new DataEnumerator(
Main.getStorage(listener.getVSensorConfig().getName()), prepareStatement, false, true);
return dataEnum;
}
public boolean vsUnLoading(VSensorConfig config) {
synchronized (listeners) {
logger.debug("Distributer unloading: " + listeners.size());
ArrayList<DistributionRequest> toRemove = new ArrayList<DistributionRequest>();
for (DistributionRequest listener : listeners) {
if (listener.getVSensorConfig() == config) toRemove.add(listener);
}
for (DistributionRequest listener : toRemove) {
try {
removeListener(listener);
} catch (Exception e) {
logger.error(e.getMessage(), e);
}
}
}
return true;
}
private void addListenerToCandidates(DistributionRequest listener) {
/** Locker variable should be modified EXACTLY like candidateListeners variable. */
logger.debug("Adding the listener: " + listener.toString() + " to the candidates.");
DataEnumerator dataEnum = makeDataEnum(listener);
if (dataEnum.hasMoreElements()) {
candidateListeners.put(listener, dataEnum);
locker.add(listener);
}
}
public void consume(StreamElement se, VSensorConfig config) {
synchronized (listeners) {
for (DistributionRequest listener : listeners)
if (listener.getVSensorConfig() == config) {
logger.debug(
"sending stream element "
+ (se == null ? "second-chance-se" : se.toString())
+ " produced by "
+ config.getName()
+ " to listener =>"
+ listener.toString());
if (!candidateListeners.containsKey(listener)) {
addListenerToCandidates(listener);
} else {
candidatesForNextRound.put(listener, Boolean.TRUE);
}
}
}
}
public void removeListener(DistributionRequest listener) {
synchronized (listeners) {
if (listeners.remove(listener)) {
try {
candidatesForNextRound.remove(listener);
removeListenerFromCandidates(listener);
preparedStatements.get(listener).close();
listener.close();
logger.warn(
"Removing listener completely from Distributer [Listener: "
+ listener.toString()
+ "]");
} catch (SQLException e) {
logger.error(e.getMessage(), e);
} finally {
preparedStatements.remove(listener);
}
}
}
}
private void removeListenerFromCandidates(DistributionRequest listener) {
/** Locker variable should be modified EXACTLY like candidateListeners variable. */
logger.debug("Updating the candidate list [" + listener.toString() + " (removed)].");
if (candidatesForNextRound.contains(listener)) {
candidateListeners.put(listener, makeDataEnum(listener));
candidatesForNextRound.remove(listener);
} else {
locker.remove(listener);
candidateListeners.remove(listener);
}
}
/**
* This method only flushes one single stream element from the provided data enumerator. Returns
* false if the flushing the stream element fails. This method also cleans the prepared statements
* by removing the listener completely.
*
* @param dataEnum
* @param listener
* @return
*/
private boolean flushStreamElement(DataEnumerator dataEnum, DistributionRequest listener) {
if (listener.isClosed()) {
logger.debug(
"Flushing an stream element failed, isClosed=true [Listener: "
+ listener.toString()
+ "]");
return false;
}
if (!dataEnum.hasMoreElements()) {
logger.debug("Nothing to flush to [Listener: " + listener.toString() + "]");
return true;
}
StreamElement se = dataEnum.nextElement();
// boolean success = true;
boolean success = listener.deliverStreamElement(se);
if (!success) {
logger.debug(
"FLushing an stream element failed, delivery failure [Listener: "
+ listener.toString()
+ "]");
return false;
}
logger.debug("Flushing an stream element succeed [Listener: " + listener.toString() + "]");
return true;
}
public void addListener(DistributionRequest listener) {
synchronized (listeners) {
if (!listeners.contains(listener)) {
logger.warn("Adding a listener to Distributer:" + listener.toString());
boolean needsAnd =
SQLValidator.removeSingleQuotes(SQLValidator.removeQuotes(listener.getQuery()))
.indexOf(" where ")
> 0;
String query = SQLValidator.addPkField(listener.getQuery());
if (needsAnd) query += " AND ";
else query += " WHERE ";
query += " timed > " + listener.getStartTime() + " and pk > ? order by timed asc ";
PreparedStatement prepareStatement = null;
try {
prepareStatement =
getPersistantConnection(listener.getVSensorConfig())
.prepareStatement(
query); // prepareStatement =
// StorageManager.getInstance().getConnection().prepareStatement(query);
prepareStatement.setMaxRows(1000); // Limit the number of rows loaded in memory.
} catch (Exception e) {
throw new RuntimeException(e);
}
preparedStatements.put(listener, prepareStatement);
listeners.add(listener);
addListenerToCandidates(listener);
} else {
logger.warn(
"Adding a listener to Distributer failed, duplicated listener! " + listener.toString());
}
}
}