How to use

forPredicate

method

in

org.apache.ignite.cluster.ClusterGroup

/**
 * @param idx Node index.
 * @param job Runnable job.
 * @param p Optional node predicate.
 * @return Future object.
 */
private IgniteFuture<?> broadcast(int idx, IgniteRunnable job, @Nullable IgnitePredicate<ClusterNode> p) {
  assert idx >= 0 && idx < NODES_CNT;
  assert job != null;
  execCntr.set(0);
  ClusterGroup prj = grid(idx).cluster();
  if (p != null)
    prj = prj.forPredicate(p);
  return compute(prj).broadcastAsync(job);
}

/** {@inheritDoc} */
@Override public IgniteInternalFuture<Long> sizeLongAsync(final int part, final CachePeekMode[] peekModes) {
  assert peekModes != null;
  final PeekModes modes = parsePeekModes(peekModes, true);
  IgniteClusterEx cluster = ctx.grid().cluster();
  final GridCacheAffinityManager aff = ctx.affinity();
  final AffinityTopologyVersion topVer = aff.affinityTopologyVersion();
  ClusterGroup grp = cluster.forDataNodes(name());
  Collection<ClusterNode> nodes = new ArrayList<>(grp.forPredicate(new IgnitePredicate<ClusterNode>() {
    /** {@inheritDoc} */
    @Override public boolean apply(ClusterNode clusterNode) {
      return ((modes.primary && aff.primaryByPartition(clusterNode, part, topVer)) ||
          (modes.backup && aff.backupByPartition(clusterNode, part, topVer)));
    }
  }).nodes());
  if (nodes.isEmpty())
    return new GridFinishedFuture<>(0L);
  ctx.kernalContext().task().setThreadContext(TC_SUBGRID, nodes);
  return ctx.kernalContext().task().execute(
    new PartitionSizeLongTask(ctx.name(), ctx.affinity().affinityTopologyVersion(), peekModes, part), null);
}

Integer res = (Integer)compute(nodes.forPredicate(p)).withTimeout(10000).
  execute(JobFailTask.class.getName(), "1");

ClusterGroup evenYoungest = remotes.forPredicate(evenP).forYoungest();
ClusterGroup evenOldest = remotes.forPredicate(evenP).forOldest();
ClusterGroup oddYoungest = remotes.forPredicate(oddP).forYoungest();
ClusterGroup oddOldest = remotes.forPredicate(oddP).forOldest();

@Override
public WorkerSet getWorkersSet(final Complexity complexity) {
  final ClusterGroup grp = ignite.cluster()
      .forServers()
      .forPredicate((node) 
          -> node.metrics().getHeapMemoryTotal() >= complexity.getRamUsage() * IGNITE_RAM_MULT_FACTOR);
  return new WorkerSetImpl(ignite, grp);
}

/** {@inheritDoc} */
@Override public IgniteInternalFuture<Long> sizeLongAsync(final int part, final CachePeekMode[] peekModes) {
  assert peekModes != null;
  final PeekModes modes = parsePeekModes(peekModes, true);
  IgniteClusterEx cluster = ctx.grid().cluster();
  final GridCacheAffinityManager aff = ctx.affinity();
  final AffinityTopologyVersion topVer = aff.affinityTopologyVersion();
  ClusterGroup grp = cluster.forDataNodes(name());
  Collection<ClusterNode> nodes = new ArrayList<>(grp.forPredicate(new IgnitePredicate<ClusterNode>() {
    /** {@inheritDoc} */
    @Override public boolean apply(ClusterNode clusterNode) {
      return ((modes.primary && aff.primaryByPartition(clusterNode, part, topVer)) ||
          (modes.backup && aff.backupByPartition(clusterNode, part, topVer)));
    }
  }).nodes());
  if (nodes.isEmpty())
    return new GridFinishedFuture<>(0L);
  ctx.kernalContext().task().setThreadContext(TC_SUBGRID, nodes);
  return ctx.kernalContext().task().execute(
    new PartitionSizeLongTask(ctx.name(), ctx.affinity().affinityTopologyVersion(), peekModes, part), null);
}