Class IndexHashGrouping

java.lang.Object
org.apache.storm.trident.partition.IndexHashGrouping
All Implemented Interfaces:
Serializable, CustomStreamGrouping

public class IndexHashGrouping extends Object implements CustomStreamGrouping
See Also:
  • Constructor Details

    • IndexHashGrouping

      public IndexHashGrouping(int index)
  • Method Details

    • objectToIndex

      public static int objectToIndex(Object val, int numPartitions)
    • prepare

      public void prepare(WorkerTopologyContext context, GlobalStreamId stream, List<Integer> targetTasks)
      Description copied from interface: 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.

      Specified by:
      prepare in interface CustomStreamGrouping
    • chooseTasks

      public List<Integer> chooseTasks(int fromTask, List<Object> values)
      Description copied from interface: 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.
      Specified by:
      chooseTasks in interface CustomStreamGrouping
      values - the values to group on