public class GlobalGrouping extends Object implements CustomStreamGrouping
Constructor and Description |
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GlobalGrouping() |
Modifier and Type | Method and Description |
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List<Integer> |
chooseTasks(int i,
List<Object> list)
This function implements a custom stream grouping.
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void |
prepare(WorkerTopologyContext context,
GlobalStreamId stream,
List<Integer> targets)
Tells the stream grouping at runtime the tasks in the target bolt.
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public void prepare(WorkerTopologyContext context, GlobalStreamId stream, List<Integer> targets)
CustomStreamGrouping
Tells the stream grouping at runtime the tasks in the target bolt. This information should be used in chooseTasks to determine the target tasks.
It also tells the grouping the metadata on the stream this grouping will be used on.
prepare
in interface CustomStreamGrouping
public List<Integer> chooseTasks(int i, List<Object> list)
CustomStreamGrouping
This function implements a custom stream grouping. It takes in as input the number of tasks in the target bolt in prepare and returns the tasks to send the tuples to.
chooseTasks
in interface CustomStreamGrouping
list
- the values to group onCopyright © 2019 The Apache Software Foundation. All Rights Reserved.