在Storm中,可以通過定義不同的bolt和spout組件,來實現數據流的動態路由和轉發。以下是一種實現方式:
public class RouterBolt extends BaseRichBolt {
private OutputCollector collector;
@Override
public void prepare(Map<String, Object> topoConf, TopologyContext context, OutputCollector collector) {
this.collector = collector;
}
@Override
public void execute(Tuple input) {
// 根據數據特征信息動態路由數據到不同的目標bolt
if (input.contains("feature1")) {
collector.emit("bolt1", new Values(input.getValueByField("field1")));
} else if (input.contains("feature2")) {
collector.emit("bolt2", new Values(input.getValueByField("field2")));
}
collector.ack(input);
}
@Override
public void declareOutputFields(OutputFieldsDeclarer declarer) {
declarer.declareStream("bolt1", new Fields("field1"));
declarer.declareStream("bolt2", new Fields("field2"));
}
}
public class Bolt1 extends BaseRichBolt {
private OutputCollector collector;
@Override
public void prepare(Map<String, Object> topoConf, TopologyContext context, OutputCollector collector) {
this.collector = collector;
}
@Override
public void execute(Tuple input) {
// 對接收到的數據進行處理
String field1 = input.getStringByField("field1");
// 處理邏輯
collector.ack(input);
}
@Override
public void declareOutputFields(OutputFieldsDeclarer declarer) {
// 不需要聲明輸出字段
}
}
public class MySpout extends BaseRichSpout {
private SpoutOutputCollector collector;
@Override
public void open(Map<String, Object> conf, TopologyContext context, SpoutOutputCollector collector) {
this.collector = collector;
}
@Override
public void nextTuple() {
// 發送數據到router bolt
collector.emit(new Values("data1"));
collector.emit(new Values("data2"));
}
@Override
public void declareOutputFields(OutputFieldsDeclarer declarer) {
declarer.declare(new Fields("field"));
}
}
通過以上方式,可以實現在Storm中對數據流進行動態路由和轉發。開發者可以根據具體需求,在router bolt中定義不同的規則和條件,來實現數據的靈活處理和路由。