Storm-源码分析-Streaming Grouping (backtype.storm.daemon.executor)
executor在发送outbounding message的时候, 需要决定发送到next component的哪些tasks 这里就需要用到streaming grouping, 1. mk-grouper 除了direct grouping, 返回的是grouper function, 执行该grouper function得到target tasks list direct grouping返回, :direct (defn- mk-grouper "Returns a function that returns a vector of which task indices to send tuple to, or just a single task index." [^WorkerTopologyContext context component-id stream-id ^Fields out-fields thrift-grouping ^List target-tasks] (let [num-tasks (count target-tasks) random (R...