/**
* @param rmtReducer Optional reducer.
* @param rmtTransform Optional transformer.
* @param args Arguments.
* @return Future.
*/
@SuppressWarnings("IfMayBeConditional")
private <R> CacheQueryFuture<R> execute(
@Nullable IgniteReducer<T, R> rmtReducer,
@Nullable IgniteClosure<T, R> rmtTransform,
@Nullable Object... args) {
Collection<ClusterNode> nodes = nodes();
cctx.checkSecurity(SecurityPermission.CACHE_READ);
if (nodes.isEmpty())
return new GridCacheQueryErrorFuture<>(
cctx.kernalContext(), new ClusterGroupEmptyCheckedException());
if (log.isDebugEnabled())
log.debug("Executing query [query=" + this + ", nodes=" + nodes + ']');
if (cctx.deploymentEnabled()) {
try {
cctx.deploy().registerClasses(filter, rmtReducer, rmtTransform);
cctx.deploy().registerClasses(args);
} catch (IgniteCheckedException e) {
return new GridCacheQueryErrorFuture<>(cctx.kernalContext(), e);
}
}
if (subjId == null) subjId = cctx.localNodeId();
taskHash = cctx.kernalContext().job().currentTaskNameHash();
final GridCacheQueryBean bean =
new GridCacheQueryBean(
this,
(IgniteReducer<Object, Object>) rmtReducer,
(IgniteClosure<Object, Object>) rmtTransform,
args);
final GridCacheQueryManager qryMgr = cctx.queries();
boolean loc = nodes.size() == 1 && F.first(nodes).id().equals(cctx.localNodeId());
if (type == SQL_FIELDS || type == SPI)
return (CacheQueryFuture<R>)
(loc ? qryMgr.queryFieldsLocal(bean) : qryMgr.queryFieldsDistributed(bean, nodes));
else if (type == SCAN && part != null && nodes.size() > 1)
return new CacheQueryFallbackFuture<>(nodes, bean, qryMgr);
else
return (CacheQueryFuture<R>)
(loc ? qryMgr.queryLocal(bean) : qryMgr.queryDistributed(bean, nodes));
}
/**
* Gets random value from given collection.
*
* @param c Input collection (no {@code null} and not emtpy).
* @return Random value from the input collection.
*/
@SuppressWarnings("UnusedDeclaration")
private static <T> T rand(Collection<? extends T> c) {
if (c == null) throw new IllegalArgumentException();
int n = ThreadLocalRandom.current().nextInt(c.size());
int i = 0;
for (T t : c) {
if (i++ == n) return t;
}
throw new ConcurrentModificationException();
}