ride-cleansing/src/main/java/org/apache/flink/training/exercises/ridecleansing/RideCleansingExercise.java

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 * 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
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 *     http://www.apache.org/licenses/LICENSE-2.0
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 * See the License for the specific language governing permissions and
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package org.apache.flink.training.exercises.ridecleansing;

import org.apache.flink.api.common.JobExecutionResult;
import org.apache.flink.api.common.functions.FilterFunction;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.functions.sink.PrintSinkFunction;
import org.apache.flink.streaming.api.functions.sink.SinkFunction;
import org.apache.flink.streaming.api.functions.source.SourceFunction;
import org.apache.flink.training.exercises.common.datatypes.TaxiRide;
import org.apache.flink.training.exercises.common.sources.TaxiRideGenerator;
import org.apache.flink.training.exercises.common.utils.MissingSolutionException;

/**
 * The Ride Cleansing exercise from the Flink training.
 *
 * <p>The task of this exercise is to filter a data stream of taxi ride records to keep only rides
 * that both start and end within New York City. The resulting stream should be printed.
 */
public class RideCleansingExercise {

    private final SourceFunction<TaxiRide> source;
    private final SinkFunction<TaxiRide> sink;

    /** Creates a job using the source and sink provided. */
    public RideCleansingExercise(SourceFunction<TaxiRide> source, SinkFunction<TaxiRide> sink) {

        this.source = source;
        this.sink = sink;
    }

    /**
     * Main method.
     *
     * @throws Exception which occurs during job execution.
     */
    public static void main(String[] args) throws Exception {
        RideCleansingExercise job =
                new RideCleansingExercise(new TaxiRideGenerator(), new PrintSinkFunction<>());

        job.execute();
    }

    /**
     * Creates and executes the long rides pipeline.
     *
     * @return {JobExecutionResult}
     * @throws Exception which occurs during job execution.
     */
    public JobExecutionResult execute() throws Exception {

        // set up streaming execution environment
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();

        // set up the pipeline
        env.addSource(source).filter(new NYCFilter()).addSink(sink);

        // run the pipeline and return the result
        return env.execute("Taxi Ride Cleansing");
    }

    /** Keep only those rides and both start and end in NYC. */
    public static class NYCFilter implements FilterFunction<TaxiRide> {
        @Override
        public boolean filter(TaxiRide taxiRide) throws Exception {
            throw new MissingSolutionException();
        }
    }
}