org.apache.storm.topology

Class WindowedBoltExecutor

java.lang.Object

org.apache.storm.topology.WindowedBoltExecutor

All Implemented Interfaces:

Serializable, IBolt, IComponent, IRichBolt

Direct Known Subclasses:

PersistentWindowedBoltExecutor, StatefulWindowedBoltExecutor

public class WindowedBoltExecutor
extends Object
implements IRichBolt

An IWindowedBolt wrapper that does the windowing of tuples.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static String	LATE_TUPLE_FIELD

Constructor Summary

Constructors

Constructor and Description
WindowedBoltExecutor(IWindowedBolt bolt)

Method Summary

Modifier and Type	Method and Description
protected void	boltExecute(List<Tuple> tuples, List<Tuple> newTuples, List<Tuple> expiredTuples, Long timestamp)
protected void	boltExecute(Supplier<Iterator<Tuple>> tuples, Supplier<Iterator<Tuple>> newTuples, Supplier<Iterator<Tuple>> expiredTuples, Long timestamp)
void	cleanup() Called when an IBolt is going to be shutdown.
void	declareOutputFields(OutputFieldsDeclarer declarer) Declare the output schema for all the streams of this topology.
protected void	doPrepare(Map<String,Object> topoConf, TopologyContext context, OutputCollector collector, Collection<Event<Tuple>> queue, boolean stateful)
void	execute(Tuple input) Process a single tuple of input.
Map<String,Object>	getComponentConfiguration() Declare configuration specific to this component.
protected Map<String,Optional<?>>	getState()
protected int	getTopologyTimeoutMillis(Map<String,Object> topoConf)
protected WindowLifecycleListener<Tuple>	newWindowLifecycleListener()
void	prepare(Map<String,Object> topoConf, TopologyContext context, OutputCollector collector) Called when a task for this component is initialized within a worker on the cluster.
protected void	restoreState(Map<String,Optional<?>> state)
protected void	start() Start the trigger policy and waterMarkEventGenerator if set.
protected void	validate(Map<String,Object> topoConf, BaseWindowedBolt.Count windowLengthCount, BaseWindowedBolt.Duration windowLengthDuration, BaseWindowedBolt.Count slidingIntervalCount, BaseWindowedBolt.Duration slidingIntervalDuration)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

LATE_TUPLE_FIELD

public static final String LATE_TUPLE_FIELD

See Also:

Constant Field Values

Constructor Detail

WindowedBoltExecutor

public WindowedBoltExecutor(IWindowedBolt bolt)

Method Detail

getTopologyTimeoutMillis

protected int getTopologyTimeoutMillis(Map<String,Object> topoConf)

validate

protected void validate(Map<String,Object> topoConf,
                        BaseWindowedBolt.Count windowLengthCount,
                        BaseWindowedBolt.Duration windowLengthDuration,
                        BaseWindowedBolt.Count slidingIntervalCount,
                        BaseWindowedBolt.Duration slidingIntervalDuration)

restoreState

protected void restoreState(Map<String,Optional<?>> state)

getState

protected Map<String,Optional<?>> getState()

start

protected void start()

Start the trigger policy and waterMarkEventGenerator if set.

prepare

public void prepare(Map<String,Object> topoConf,
                    TopologyContext context,
                    OutputCollector collector)

Description copied from interface: IBolt

Called when a task for this component is initialized within a worker on the cluster. It provides the bolt with the environment in which the bolt executes.

This includes the:

Specified by:

prepare in interface IBolt

Parameters:

topoConf - The Storm configuration for this bolt. This is the configuration provided to the topology merged in with cluster configuration on this machine.

context - This object can be used to get information about this task's place within the topology, including the task id and component id of this task, input and output information, etc.

collector - The collector is used to emit tuples from this bolt. Tuples can be emitted at any time, including the prepare and cleanup methods. The collector is thread-safe and should be saved as an instance variable of this bolt object.

doPrepare

protected void doPrepare(Map<String,Object> topoConf,
                         TopologyContext context,
                         OutputCollector collector,
                         Collection<Event<Tuple>> queue,
                         boolean stateful)

execute

public void execute(Tuple input)

Description copied from interface: IBolt

Process a single tuple of input. The Tuple object contains metadata on it about which component/stream/task it came from. The values of the Tuple can be accessed using Tuple#getValue. The IBolt does not have to process the Tuple immediately. It is perfectly fine to hang onto a tuple and process it later (for instance, to do an aggregation or join).

Tuples should be emitted using the OutputCollector provided through the prepare method. It is required that all input tuples are acked or failed at some point using the OutputCollector. Otherwise, Storm will be unable to determine when tuples coming off the spouts have been completed.

For the common case of acking an input tuple at the end of the execute method, see IBasicBolt which automates this.

Specified by:

execute in interface IBolt

Parameters:

input - The input tuple to be processed.

cleanup

public void cleanup()

Description copied from interface: IBolt

Called when an IBolt is going to be shutdown. Storm will make a best-effort attempt to call this if the worker shutdown is orderly. The Config.SUPERVISOR_WORKER_SHUTDOWN_SLEEP_SECS setting controls how long orderly shutdown is allowed to take. There is no guarantee that cleanup will be called if shutdown is not orderly, or if the shutdown exceeds the time limit.

The one context where cleanup is guaranteed to be called is when a topology is killed when running Storm in local mode.

Specified by:

cleanup in interface IBolt

declareOutputFields

public void declareOutputFields(OutputFieldsDeclarer declarer)

Description copied from interface: IComponent

Declare the output schema for all the streams of this topology.

Specified by:

declareOutputFields in interface IComponent

Parameters:

declarer - this is used to declare output stream ids, output fields, and whether or not each output stream is a direct stream

getComponentConfiguration

public Map<String,Object> getComponentConfiguration()

Description copied from interface: IComponent

Declare configuration specific to this component. Only a subset of the "topology.*" configs can be overridden. The component configuration can be further overridden when constructing the topology using TopologyBuilder

Specified by:

getComponentConfiguration in interface IComponent

newWindowLifecycleListener

protected WindowLifecycleListener<Tuple> newWindowLifecycleListener()

boltExecute

protected void boltExecute(List<Tuple> tuples,
                           List<Tuple> newTuples,
                           List<Tuple> expiredTuples,
                           Long timestamp)

boltExecute

protected void boltExecute(Supplier<Iterator<Tuple>> tuples,
                           Supplier<Iterator<Tuple>> newTuples,
                           Supplier<Iterator<Tuple>> expiredTuples,
                           Long timestamp)