org.apache.storm.trident.operation

Interface TridentCollector

All Known Implementing Classes:

AppendCollector, CaptureCollector, FreshCollector, GroupCollector

public interface TridentCollector

Interface for publishing tuples to a stream and reporting exceptions (to be displayed in Storm UI).

Trident components that have the ability to emit tuples to a stream are passed an instance of this interface.

For example, to emit a new tuple to a stream, you would do something like the following:

java collector.emit(new Values("a", "b", "c"));

See Also:

Stream, Values

Method Summary

Modifier and Type	Method and Description
void	emit(List<Object> values) Emits a tuple to a Stream.
void	flush() Flush any buffered tuples (when batching is enabled).
void	reportError(Throwable t) Reports an error.

Method Detail

emit

void emit(List<Object> values)

Emits a tuple to a Stream.

Parameters:

values - a list of values of which the tuple will be composed

flush

void flush()

Flush any buffered tuples (when batching is enabled).

reportError

void reportError(Throwable t)

Reports an error. The corresponding stack trace will be visible in the Storm UI.

Note that calling this method does not alter the processing of a batch. To explicitly fail a batch and trigger a replay, components should throw FailedException.

Parameters:

t - The instance of the error (Throwable) being reported.