Topology configuration example

Storm topology can be configured by the TopologyBuilder class by creating spouts and bolts, and then by submitting the topology.

Spouts

Some implementations of spouts are available in Storm, such as BaseRichSpout, ClojureSpout, DRPCSpout, FeederSpout, FixedTupleSpout, MasterBatchCoordinator, RichShellSpout, RichSpoutBatchTriggerer, ShellSpout, SpoutTracker, TestPlannerSpout, TestWordSpout, and TransactionalSpoutCoordinator.

We can write a custom bolts by extending any of the aforementioned classes or implementing the ISpout interface:

public class NumberSpout extends BaseRichSpout 
{
    private SpoutOutputCollector collector;
    
    private static int currentNumber = 1;
        
    @Override
    public void open( Map conf, TopologyContext context, SpoutOutputCollector collector ) 
    {
        this.collector = collector;
    }
    
    @Override
    public void nextTuple() 
    {

        // Emit the next number
        collector.emit( new Values( new Integer...