/**
* Execute the provided query asynchronously.
*
* <p>This method does not block. It returns as soon as the query has been successfully sent to a
* Cassandra node. In particular, returning from this method does not guarantee that the query is
* valid. Any exception pertaining to the failure of the query will be thrown by the first access
* to the {@link ResultSet}.
*
* <p>Note that for queries that doesn't return a result (INSERT, UPDATE and DELETE), you will
* need to access the ResultSet (i.e. call any of its method) to make sure the query was
* successful.
*
* @param query the CQL query to execute (that can be either a {@code Statement} or a {@code
* BoundStatement}). If it is a {@code BoundStatement}, all variables must have been bound
* (the statement must be ready).
* @return a future on the result of the query.
* @throws IllegalStateException if {@code query} is a {@code BoundStatement} but {@code
* !query.isReady()}.
*/
public ResultSetFuture executeAsync(Query query) {
if (query instanceof Statement) {
return manager.executeQuery(
new QueryMessage(
((Statement) query).getQueryString(),
ConsistencyLevel.toCassandraCL(query.getConsistencyLevel())),
query);
} else {
assert query instanceof BoundStatement : query;
BoundStatement bs = (BoundStatement) query;
if (!bs.isReady())
throw new IllegalStateException(
"Some bind variables haven't been bound in the provided statement");
return manager.executeQuery(
new ExecuteMessage(
bs.statement.id,
Arrays.asList(bs.values),
ConsistencyLevel.toCassandraCL(query.getConsistencyLevel())),
query);
}
}
/** Loops collecting cql binded variable values from the queue and sending to Cassandra */
public void run() {
outer:
while (run || !queue.isEmpty()) {
List<ByteBuffer> bindVariables;
try {
bindVariables = queue.take();
} catch (InterruptedException e) {
// re-check loop condition after interrupt
continue;
}
ListIterator<InetAddress> iter = endpoints.listIterator();
while (true) {
// send the mutation to the last-used endpoint. first time through, this will NPE
// harmlessly.
try {
int i = 0;
PreparedStatement statement = preparedStatement(client);
while (bindVariables != null) {
BoundStatement boundStatement = new BoundStatement(statement);
for (int columnPosition = 0;
columnPosition < bindVariables.size();
columnPosition++) {
boundStatement.setBytesUnsafe(columnPosition, bindVariables.get(columnPosition));
}
client.execute(boundStatement);
i++;
if (i >= batchThreshold) break;
bindVariables = queue.poll();
}
break;
} catch (Exception e) {
closeInternal();
if (!iter.hasNext()) {
lastException = new IOException(e);
break outer;
}
}
// attempt to connect to a different endpoint
try {
InetAddress address = iter.next();
String host = address.getHostName();
client = CqlConfigHelper.getOutputCluster(host, conf).connect();
} catch (Exception e) {
// If connection died due to Interrupt, just try connecting to the endpoint again.
// There are too many ways for the Thread.interrupted() state to be cleared, so
// we can't rely on that here. Until the java driver gives us a better way of knowing
// that this exception came from an InterruptedException, this is the best solution.
if (canRetryDriverConnection(e)) {
iter.previous();
}
closeInternal();
// Most exceptions mean something unexpected went wrong to that endpoint, so
// we should try again to another. Other exceptions (auth or invalid request) are
// fatal.
if ((e instanceof AuthenticationException || e instanceof InvalidQueryException)
|| !iter.hasNext()) {
lastException = new IOException(e);
break outer;
}
}
}
}
// close all our connections once we are done.
closeInternal();
}