/** {@inheritDoc} */
@Override
public String reduce(List<GridComputeJobResult> results) throws GridException {
int sum = 0;
String locNodeId = null;
for (GridComputeJobResult res : results) {
GridBiTuple<String, Integer> part = res.getData();
if (locNodeId == null) locNodeId = part.get1();
Integer i = part.get2();
if (i != null) sum += i;
}
assert gridSize == sum;
return locNodeId;
}
/**
* Default implementation which will wait for all jobs to complete before calling {@link
* #reduce(List)} method.
*
* <p>If remote job resulted in exception ({@link GridComputeJobResult#getException()} is not
* {@code null}), then {@link GridComputeJobResultPolicy#FAILOVER} policy will be returned if the
* exception is instance of {@link GridTopologyException} or {@link
* GridComputeExecutionRejectedException}, which means that remote node either failed or job
* execution was rejected before it got a chance to start. In all other cases the exception will
* be rethrown which will ultimately cause task to fail.
*
* @param res Received remote grid executable result.
* @param rcvd All previously received results.
* @return Result policy that dictates how to process further upcoming job results.
* @throws GridException If handling a job result caused an error effectively rejecting a
* failover. This exception will be thrown out of {@link GridComputeTaskFuture#get()} method.
*/
@Override
public GridComputeJobResultPolicy result(
GridComputeJobResult res, List<GridComputeJobResult> rcvd) throws GridException {
GridException e = res.getException();
// Try to failover if result is failed.
if (e != null) {
// Don't failover user's code errors.
if (e instanceof GridComputeExecutionRejectedException
|| e instanceof GridTopologyException
||
// Failover exception is always wrapped.
e.hasCause(GridComputeJobFailoverException.class)) return FAILOVER;
throw new GridException(
"Remote job threw user exception (override or implement GridComputeTask.result(..) "
+ "method if you would like to have automatic failover for this exception).",
e);
}
// Wait for all job responses.
return WAIT;
}
