FunctionChain.java

/*
    BeepBeep, an event stream processor
    Copyright (C) 2008-2016 Sylvain Hallé

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License as published
    by the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package functions;

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

/**
 * Pipe multiple
 * {@link ca.uqac.lif.cep.functions.ApplyFunction ApplyFunction} processors
 * to perform a more complex computation over a stream.
 * The chain of processors in this example can be represented
 * graphically as:
 * <p>
 * <img src="./doc-files/functions/FunctionChain.png" alt="Processor graph">
 * @author Sylvain Hallé
 * @difficulty Easy
 */
public class FunctionChain
{
    public static void main (String[] args)
    {
        ///
        QueueSource source1 = new QueueSource().setEvents(2, 7, 1, 8, 3);
        QueueSource source2 = new QueueSource().setEvents(3, 1, 4, 1, 6);
        QueueSource source3 = new QueueSource().setEvents(1, 1, 2, 3, 5);
        ApplyFunction add = new ApplyFunction(Numbers.addition);
        Connector.connect(source1, 0, add, 0);
        Connector.connect(source2, 0, add, 1);
        ApplyFunction mul = new ApplyFunction(Numbers.multiplication);
        Connector.connect(source3, 0, mul, 0);
        Connector.connect(add, 0, mul, 1);
        Pullable p = mul.getPullableOutput();
        for (int i = 0; i < 5; i++)
        {
            float x = (Float) p.pull();
            System.out.println("The event is: " + x);
        }
        ///
    }
}