Strom的trident小例子

上代码:

 public class TridentFunc {

     /**
      * 类似于普通的bolt
      */
     public static class MyFunction extends BaseFunction{
         @Override
         public void execute(TridentTuple tuple, TridentCollector collector) {
             Integer value = tuple.getIntegerByField("sentence");
             System.out.println(value);
         }
     }

     public static void main(String[] args) {
         @SuppressWarnings("unchecked")
         FixedBatchSpout spout = new FixedBatchSpout(new Fields("sentence"), 1, new Values(1),new Values(2));
         spout.setCycle(true);//让spout循环发送数据

         TridentTopology tridentTopology = new TridentTopology();
         tridentTopology.newStream("spoutid",spout)
             .each(new Fields("sentence"), new MyFunction(), new Fields(""));

         LocalCluster localCluster = new LocalCluster();
         String simpleName = TridentFunc.class.getSimpleName();
         localCluster.submitTopology(simpleName, new Config(), tridentTopology.build());
         //运行结果就是  一直循环打印 1 2 1 2
     }
 }

多数据源

 public class TridentMeger {

     /**
      * 类似于普通的bolt
      */
     public static class MyFunction extends BaseFunction{
         @Override
         public void execute(TridentTuple tuple, TridentCollector collector) {
             Integer value = tuple.getIntegerByField("sentence");
             System.out.println(value);
         }
     }

     public static void main(String[] args) {
         FixedBatchSpout spout = new FixedBatchSpout(new Fields("sentence"), 1, new Values(1),new Values(2));
         //spout.setCycle(true);//让spout循环发送数据

         TridentTopology tridentTopology = new TridentTopology();
         //指定多个数据源，流连接
         Stream newStream1 = tridentTopology.newStream("spoutid1",spout);
         Stream newStream2 = tridentTopology.newStream("spoutid2",spout);

         //tridentTopology.newStream("spoutid",spout) 之前是这种  但是只能有 一个数据源
         tridentTopology.merge(newStream1,newStream2)//使用这种就可以有多个数据源.
             .each(new Fields("sentence"), new MyFunction(), new Fields(""));

         LocalCluster localCluster = new LocalCluster();
         String simpleName = TridentMeger.class.getSimpleName();
         localCluster.submitTopology(simpleName, new Config(), tridentTopology.build());
     }
 }

增加过滤器

 public class TridentFilter {

     /**
      * 类似于普通的bolt
      */
     public static class MyFunction extends BaseFunction{
         @Override
         public void execute(TridentTuple tuple, TridentCollector collector) {
             Integer value = tuple.getIntegerByField("sentence");
             System.out.println(value);
         }
     }

     public static class MyFilter extends BaseFilter{//专门封装了一个Filter功能.
         //对数据进行过滤  如果过滤出的数据不要了就false 保留就ture
         @Override
         public boolean isKeep(TridentTuple tuple) {
             Integer value = tuple.getIntegerByField("sentence");
             return value%2==0?true:false; //只要偶数不要奇数
         }
     }

     public static void main(String[] args) {
         FixedBatchSpout spout = new FixedBatchSpout(new Fields("sentence"), 1, new Values(1),new Values(2));
         spout.setCycle(true);//让spout循环发送数据

         TridentTopology tridentTopology = new TridentTopology();
         tridentTopology.newStream("spoutid",spout)     //这个地方只能指定一个数据源,如果想指定多个数据源Spout 看TridentMeger.java
             .each(new Fields("sentence"), new MyFilter())
             .each(new Fields("sentence"), new MyFunction(), new Fields(""));

         LocalCluster localCluster = new LocalCluster();
         String simpleName = TridentFilter.class.getSimpleName();
         localCluster.submitTopology(simpleName, new Config(), tridentTopology.build());
     }
 }