public class SolrFieldsSpout extends BaseRichSpout
Modifier and Type | Field and Description |
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static List<Values> |
listValues |
Constructor and Description |
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SolrFieldsSpout() |
Modifier and Type | Method and Description |
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void |
close()
Called when an ISpout is going to be shutdown.
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void |
declareOutputFields(OutputFieldsDeclarer declarer)
Declare the output schema for all the streams of this topology.
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Fields |
getOutputFields() |
void |
nextTuple()
When this method is called, Storm is requesting that the Spout emit tuples to the output collector.
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void |
open(Map conf,
TopologyContext context,
SpoutOutputCollector collector)
Called when a task for this component is initialized within a worker on the cluster.
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ack, activate, deactivate, fail
getComponentConfiguration
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
getComponentConfiguration
public void open(Map conf, TopologyContext context, SpoutOutputCollector collector)
ISpout
Called when a task for this component is initialized within a worker on the cluster. It provides the spout with the environment in which the spout executes.
This includes the:
conf
- The Storm configuration for this spout. 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 spout. Tuples can be emitted at any time, including the open and close methods. The collector is thread-safe and should be saved as an instance variable of this spout object.public void nextTuple()
ISpout
When this method is called, Storm is requesting that the Spout emit tuples to the output collector. This method should be non-blocking, so if the Spout has no tuples to emit, this method should return. nextTuple, ack, and fail are all called in a tight loop in a single thread in the spout task. When there are no tuples to emit, it is courteous to have nextTuple sleep for a short amount of time (like a single millisecond) so as not to waste too much CPU.
public void declareOutputFields(OutputFieldsDeclarer declarer)
IComponent
Declare the output schema for all the streams of this topology.
declarer
- this is used to declare output stream ids, output fields, and whether or not each output stream is a direct streampublic Fields getOutputFields()
public void close()
ISpout
Called when an ISpout is going to be shutdown. There is no guarentee that close will be called, because the supervisor kill -9’s worker processes on the cluster.
The one context where close is guaranteed to be called is a topology is killed when running Storm in local mode.
close
in interface ISpout
close
in class BaseRichSpout
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