package backtype.storm.task;
import backtype.storm.tuple.Tuple;
import backtype.storm.utils.Utils;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
/**
* This output collector exposes the API for emitting tuples from an IRichBolt.
* This is the core API for emitting tuples. For a simpler API, and a more
* restricted form of stream processing, see IBasicBolt and
* BasicOutputCollector.
*/
public class OutputCollector implements IOutputCollector {
private IOutputCollector _delegate;
public OutputCollector(IOutputCollector delegate) {
_delegate = delegate;
}
/**
* Emits a new tuple to a specific stream with a single anchor. The emitted
* values must be immutable.
*
* @param streamId
* the stream to emit to
* @param anchor
* the tuple to anchor to
* @param tuple
* the new output tuple from this bolt
* @return the list of task ids that this new tuple was sent to
*/
public List<Integer> emit(String streamId, Tuple anchor, List<Object> tuple) {
return emit(streamId, Arrays.asList(anchor), tuple);
}
/**
* Emits a new unanchored tuple to the specified stream. Because it's
* unanchored, if a failure happens downstream, this new tuple won't affect
* whether any spout tuples are considered failed or not. The emitted values
* must be immutable.
*
* @param streamId
* the stream to emit to
* @param tuple
* the new output tuple from this bolt
* @return the list of task ids that this new tuple was sent to
*/
public List<Integer> emit(String streamId, List<Object> tuple) {
return emit(streamId, (List) null, tuple);
}
/**
* Emits a new tuple to the default stream anchored on a group of input
* tuples. The emitted values must be immutable.
*
* @param anchors
* the tuples to anchor to
* @param tuple
* the new output tuple from this bolt
* @return the list of task ids that this new tuple was sent to
*/
public List<Integer> emit(Collection<Tuple> anchors, List<Object> tuple) {
return emit(Utils.DEFAULT_STREAM_ID, anchors, tuple);
}
/**
* Emits a new tuple to the default stream anchored on a single tuple. The
* emitted values must be immutable.
*
* @param anchor
* the tuple to anchor to
* @param tuple
* the new output tuple from this bolt
* @return the list of task ids that this new tuple was sent to
*/
public List<Integer> emit(Tuple anchor, List<Object> tuple) {
return emit(Utils.DEFAULT_STREAM_ID, anchor, tuple);
}
/**
* Emits a new unanchored tuple to the default stream. Beacuse it's
* unanchored, if a failure happens downstream, this new tuple won't affect
* whether any spout tuples are considered failed or not. The emitted values
* must be immutable.
*
* @param tuple
* the new output tuple from this bolt
* @return the list of task ids that this new tuple was sent to
*/
public List<Integer> emit(List<Object> tuple) {
return emit(Utils.DEFAULT_STREAM_ID, tuple);
}
/**
* Emits a tuple directly to the specified task id on the specified stream.
* If the target bolt does not subscribe to this bolt using a direct
* grouping, the tuple will not be sent. If the specified output stream is
* not declared as direct, or the target bolt subscribes with a non-direct
* grouping, an error will occur at runtime. The emitted values must be
* immutable.
*
* @param taskId
* the taskId to send the new tuple to
* @param streamId
* the stream to send the tuple on. It must be declared as a
* direct stream in the topology definition.
* @param anchor
* the tuple to anchor to
* @param tuple
* the new output tuple from this bolt
*/
public void emitDirect(int taskId, String streamId, Tuple anchor,
List<Object> tuple) {
emitDirect(taskId, streamId, Arrays.asList(anchor), tuple);
}
/**
* Emits a tuple directly to the specified task id on the specified stream.
* If the target bolt does not subscribe to this bolt using a direct
* grouping, the tuple will not be sent. If the specified output stream is
* not declared as direct, or the target bolt subscribes with a non-direct
* grouping, an error will occur at runtime. Note that this method does not
* use anchors, so downstream failures won't affect the failure status of
* any spout tuples. The emitted values must be immutable.
*
* @param taskId
* the taskId to send the new tuple to
* @param streamId
* the stream to send the tuple on. It must be declared as a
* direct stream in the topology definition.
* @param tuple
* the new output tuple from this bolt
*/
public void emitDirect(int taskId, String streamId, List<Object> tuple) {
emitDirect(taskId, streamId, (List) null, tuple);
}
/**
* Emits a tuple directly to the specified task id on the default stream. If
* the target bolt does not subscribe to this bolt using a direct grouping,
* the tuple will not be sent. If the specified output stream is not
* declared as direct, or the target bolt subscribes with a non-direct
* grouping, an error will occur at runtime. The emitted values must be
* immutable.
*
* <p>
* The default stream must be declared as direct in the topology definition.
* See OutputDeclarer#declare for how this is done when defining topologies
* in Java.
* </p>
*
* @param taskId
* the taskId to send the new tuple to
* @param anchosr
* the tuples to anchor to
* @param tuple
* the new output tuple from this bolt
*/
public void emitDirect(int taskId, Collection<Tuple> anchors,
List<Object> tuple) {
emitDirect(taskId, Utils.DEFAULT_STREAM_ID, anchors, tuple);
}
/**
* Emits a tuple directly to the specified task id on the default stream. If
* the target bolt does not subscribe to this bolt using a direct grouping,
* the tuple will not be sent. If the specified output stream is not
* declared as direct, or the target bolt subscribes with a non-direct
* grouping, an error will occur at runtime. The emitted values must be
* immutable.
*
* <p>
* The default stream must be declared as direct in the topology definition.
* See OutputDeclarer#declare for how this is done when defining topologies
* in Java.
* </p>
*
* @param taskId
* the taskId to send the new tuple to
* @param anchor
* the tuple to anchor to
* @param tuple
* the new output tuple from this bolt
*/
public void emitDirect(int taskId, Tuple anchor, List<Object> tuple) {
emitDirect(taskId, Utils.DEFAULT_STREAM_ID, anchor, tuple);
}
/**
* Emits a tuple directly to the specified task id on the default stream. If
* the target bolt does not subscribe to this bolt using a direct grouping,
* the tuple will not be sent. If the specified output stream is not
* declared as direct, or the target bolt subscribes with a non-direct
* grouping, an error will occur at runtime. The emitted values must be
* immutable.
*
* <p>
* The default stream must be declared as direct in the topology definition.
* See OutputDeclarer#declare for how this is done when defining topologies
* in Java.
* </p>
*
* <p>
* Note that this method does not use anchors, so downstream failures won't
* affect the failure status of any spout tuples.
* </p>
*
* @param taskId
* the taskId to send the new tuple to
* @param tuple
* the new output tuple from this bolt
*/
public void emitDirect(int taskId, List<Object> tuple) {
emitDirect(taskId, Utils.DEFAULT_STREAM_ID, tuple);
}
@Override
public List<Integer> emit(String streamId, Collection<Tuple> anchors,
List<Object> tuple) {
return _delegate.emit(streamId, anchors, tuple);
}
@Override
public void emitDirect(int taskId, String streamId,
Collection<Tuple> anchors, List<Object> tuple) {
_delegate.emitDirect(taskId, streamId, anchors, tuple);
}
@Override
public void ack(Tuple input) {
_delegate.ack(input);
}
@Override
public void fail(Tuple input) {
_delegate.fail(input);
}
@Override
public void reportError(Throwable error) {
_delegate.reportError(error);
}
}