org.calrissian.flowmix.example.JoinExample.java Source code

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Here is the source code for org.calrissian.flowmix.example.JoinExample.java

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/*
 * Copyright (C) 2014 The Calrissian Authors
 *
 * Licensed 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.calrissian.flowmix.example;

import com.google.common.collect.Iterables;
import org.calrissian.flowmix.example.support.ExampleRunner;
import org.calrissian.flowmix.example.support.FlowProvider;
import org.calrissian.flowmix.api.Flow;
import org.calrissian.flowmix.api.Policy;
import org.calrissian.flowmix.api.builder.FlowBuilder;
import org.calrissian.flowmix.api.Function;
import org.calrissian.mango.domain.event.BaseEvent;
import org.calrissian.mango.domain.event.Event;
import org.calrissian.mango.domain.Tuple;

import java.util.List;

import static java.util.Arrays.asList;
import static java.util.Collections.singletonList;

/**
 * A stream join example. The events for the left hand of the join (stream1) are collected into a window and the
 * right hand side is joined against the left hand side (that is, the tuples are merged with the right hand side).
 */
public class JoinExample implements FlowProvider {

    @Override
    public List<Flow> getFlows() {
        Flow flow = new FlowBuilder().id("flow").flowDefs().stream("stream1").each().function(new Function() {
            @Override
            public List<Event> execute(Event event) {
                Event newEvent = new BaseEvent(event.getId(), event.getTimestamp());
                newEvent.putAll(Iterables.concat(event.getTuples()));
                newEvent.put(new Tuple("stream", "stream1"));
                return singletonList(newEvent);
            }
        }).end().endStream(false, "stream3") // send ALL results to stream2 and not to standard output
                .stream("stream2") // don't read any events from standard input
                .each().function(new Function() {
                    @Override
                    public List<Event> execute(Event event) {
                        Event newEvent = new BaseEvent(event.getId(), event.getTimestamp());
                        newEvent.putAll(Iterables.concat(event.getTuples()));
                        newEvent.put(new Tuple("stream", "stream2"));
                        return singletonList(newEvent);
                    }
                }).end().endStream(false, "stream3").stream("stream3", false).join("stream1", "stream2")
                .evict(Policy.TIME, 5).end().endStream().endDefs().createFlow();

        return asList(new Flow[] { flow });
    }

    public static void main(String args[]) {
        new ExampleRunner(new JoinExample()).run();
    }
}