GroupSimple.java

package basic;

import ca.uqac.lif.cep.Connector;
import ca.uqac.lif.cep.GroupProcessor;
import ca.uqac.lif.cep.Pullable;
import ca.uqac.lif.cep.functions.ApplyFunction;
import ca.uqac.lif.cep.tmf.Fork;
import ca.uqac.lif.cep.tmf.QueueSource;
import ca.uqac.lif.cep.tmf.Trim;
import ca.uqac.lif.cep.util.Numbers;

/**
 * Encapsulate a chain of processors into a
 * {@link ca.uqac.lif.cep.Group Group}.
 * The chain of processors in this example can be
 * represented graphically as:
 * <p>
 * <img src="./doc-files/basic/GroupSimple.png" alt="Processor graph">
 * @see SumTwo
 * @author Sylvain Hallé
 * @difficulty Easy
 * {@link GroupProcessor#associateInput(int, ca.uqac.lif.cep.Processor, int) 
 */
public class GroupSimple 
{
    public static void main(String[] args)
    {
        /// Create a source of arbitrary numbers
        QueueSource source = new QueueSource().setEvents(1, 2, 3, 4, 5, 6);

        // Fork the stream in two and connect it to the source
        GroupProcessor group = new GroupProcessor(1, 1);
        {
            Fork fork = new Fork(2);
            ApplyFunction add = new ApplyFunction(Numbers.addition);
            Connector.connect(fork, 0, add, 0);
            Trim trim = new Trim(1);
            Connector.connect(fork, 1, trim, 0);
            Connector.connect(trim, 0, add, 1);
            group.addProcessors(fork, trim, add);
            group.associateInput(0, fork, 0);
            group.associateOutput(0, add, 0);
        }
        
        // Connect the source to the group
        Connector.connect(source, group);

        /* Let us now print what we receive by pulling on the output of
         * group. */
        Pullable p = group.getPullableOutput();
        for (int i = 0; i < 6; i++)
        {
            float x = (Float) p.pull();
            System.out.println("The event is: " + x);
        }
        ///
    }
}