TridentState分析

public class TridentState {
    TridentTopology _topology;
    Node _node;

    protected TridentState(TridentTopology topology, Node node) {
        _topology = topology;
        _node = node;
    }

    public Stream newValuesStream() {
        return new Stream(_topology, _node.name, _node);
    }

    public TridentState parallelismHint(int parallelism) {
        _node.parallelismHint = parallelism;
        return this;
    }
}

主要作用就是构建 TridentTopology 和node相关联的Stream