subprojects/s4-example/src/main/java/org/apache/s4/example/counter/MyApp.java

/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.s4.example.counter;

import java.util.concurrent.TimeUnit;

import org.apache.s4.base.Event;
import org.apache.s4.core.App;
import org.apache.s4.core.Receiver;
import org.apache.s4.core.Sender;
import org.apache.s4.core.Stream;

import com.google.inject.Guice;
import com.google.inject.Injector;

/*
 * This is a sample application to test a new S4 API.
 * See README file for details.
 *
 * */

final public class MyApp extends App {

    final private int interval = 1;
    private GenerateUserEventPE generateUserEventPE;

    /*
     * 
     * 
     * The application graph itself is created in this Class. However, developers may provide tools for creating apps
     * which will generate the objects.
     * 
     * IMPORTANT: we create a graph of PE prototypes. The prototype is a class instance that is used as a prototype from
     * which all PE instance will be created. The prototype itself is not used as an instance. (Except when the PE is of
     * type Singleton PE). To create a data structure for each PE instance you must do it in the method
     * ProcessingElement.onCreate().
     */

    /*
     * Build the application graph using POJOs. Don't like it? Write a nice tool.
     * 
     * @see io.s4.App#init()
     */
    @SuppressWarnings("unchecked")
    @Override
    protected void onInit() {

        /* PE that prints counts to console. */
        PrintPE printPE = createPE(PrintPE.class);

        Stream<CountEvent> userCountStream = createStream("User Count Stream", new CountKeyFinder(), printPE);

        Stream<CountEvent> genderCountStream = createStream("Gender Count Stream", new CountKeyFinder(), printPE);

        Stream<CountEvent> ageCountStream = createStream("Age Count Stream", new CountKeyFinder(), printPE);

        /* PEs that count events by user, gender, and age. */
        CounterPE userCountPE = createPE(CounterPE.class);
        userCountPE.setTrigger(Event.class, interval, 10l, TimeUnit.MILLISECONDS);
        userCountPE.setCountStream(userCountStream);

        CounterPE genderCountPE = createPE(CounterPE.class);
        genderCountPE.setTrigger(Event.class, interval, 10l, TimeUnit.MILLISECONDS);
        genderCountPE.setCountStream(genderCountStream);

        CounterPE ageCountPE = createPE(CounterPE.class);
        ageCountPE.setTrigger(Event.class, interval, 10l, TimeUnit.MILLISECONDS);
        ageCountPE.setCountStream(ageCountStream);

        /* Streams that output user events keyed on user, gender, and age. */
        Stream<UserEvent> userStream = createStream("User Stream", new UserIDKeyFinder(), userCountPE);

        Stream<UserEvent> genderStream = createStream("Gender Stream", new GenderKeyFinder(), genderCountPE);

        Stream<UserEvent> ageStream = createStream("Age Stream", new AgeKeyFinder(), ageCountPE);

        generateUserEventPE = createPE(GenerateUserEventPE.class);
        generateUserEventPE.setStreams(userStream, genderStream, ageStream);
        generateUserEventPE.setSingleton(true);
        generateUserEventPE.setTimerInterval(1, TimeUnit.MILLISECONDS);

    }

    /*
     * Create and send 200 dummy events of type UserEvent.
     * 
     * @see io.s4.App#start()
     */
    @Override
    protected void onStart() {

    }

    @Override
    protected void onClose() {
        System.out.println("Bye.");

    }

    public static void main(String[] args) {

        Injector injector = Guice.createInjector(new Module());
        MyApp myApp = injector.getInstance(MyApp.class);
        Sender sender = injector.getInstance(Sender.class);
        Receiver receiver = injector.getInstance(Receiver.class);
        // myApp.setCommLayer(sender, receiver);
        myApp.init();
        myApp.start();

        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        myApp.close();
        receiver.close();
    }
}