org.apache.beam.learning.katas.triggers.windowaccummode.Task.java Source code

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Here is the source code for org.apache.beam.learning.katas.triggers.windowaccummode.Task.java

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/*
 * 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.beam.learning.katas.triggers.windowaccummode;

import org.apache.beam.learning.katas.util.Log;
import org.apache.beam.sdk.Pipeline;
import org.apache.beam.sdk.options.PipelineOptions;
import org.apache.beam.sdk.options.PipelineOptionsFactory;
import org.apache.beam.sdk.transforms.Combine;
import org.apache.beam.sdk.transforms.Count;
import org.apache.beam.sdk.transforms.windowing.AfterProcessingTime;
import org.apache.beam.sdk.transforms.windowing.AfterWatermark;
import org.apache.beam.sdk.transforms.windowing.FixedWindows;
import org.apache.beam.sdk.transforms.windowing.Window;
import org.apache.beam.sdk.values.PCollection;
import org.joda.time.Duration;

public class Task {

    public static void main(String[] args) {
        PipelineOptions options = PipelineOptionsFactory.fromArgs(args).create();
        Pipeline pipeline = Pipeline.create(options);

        PCollection<String> events = pipeline.apply(GenerateEvent.everySecond());

        PCollection<Long> output = applyTransform(events);

        output.apply(Log.ofElements());

        pipeline.run();
    }

    static PCollection<Long> applyTransform(PCollection<String> events) {
        return events
                .apply(Window.<String>into(FixedWindows.of(Duration.standardDays(1)))
                        .triggering(AfterWatermark.pastEndOfWindow()
                                .withEarlyFirings(AfterProcessingTime.pastFirstElementInPane()))
                        .withAllowedLateness(Duration.ZERO).accumulatingFiredPanes())

                .apply(Combine.globally(Count.<String>combineFn()).withoutDefaults());
    }

}