content: /**
   * 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.apex.malhar.stream.sample.cookbook;
  
  import java.util.Arrays;
  import java.util.List;
  
  import org.joda.time.Duration;
  
  import org.apache.apex.malhar.lib.function.Function;
  import org.apache.apex.malhar.lib.window.TriggerOption;
  import org.apache.apex.malhar.lib.window.Tuple;
  import org.apache.apex.malhar.lib.window.WindowOption;
  import org.apache.apex.malhar.lib.window.accumulation.RemoveDuplicates;
  import org.apache.apex.malhar.stream.api.ApexStream;
  import org.apache.apex.malhar.stream.api.impl.StreamFactory;
  import org.apache.hadoop.conf.Configuration;
  
  import com.datatorrent.api.Context;
  import com.datatorrent.api.DAG;
  import com.datatorrent.api.DefaultInputPort;
  import com.datatorrent.api.StreamingApplication;
  import com.datatorrent.api.annotation.ApplicationAnnotation;
  import com.datatorrent.common.util.BaseOperator;
  
  import static org.apache.apex.malhar.stream.api.Option.Options.name;
  
  /**
   * Beam DeDupExample.
   *
   * @since 3.5.0
   */
  @ApplicationAnnotation(name = "DeDupExample")
  public class DeDupExample implements StreamingApplication
  {
  
    public static class Collector extends BaseOperator
    {
      private static Tuple.WindowedTuple<List<String>> result;
      private static boolean done = false;
  
      public static Tuple.WindowedTuple<List<String>> getResult()
      {
        return result;
      }
  
      public static boolean isDone()
      {
        return done;
      }
  
      @Override
      public void setup(Context.OperatorContext context)
      {
        super.setup(context);
        result = new Tuple.WindowedTuple<>();
        done = false;
      }
  
      public transient DefaultInputPort<Tuple.WindowedTuple<List<String>>> input = new DefaultInputPort<Tuple.WindowedTuple<List<String>>>()
      {
        @Override
        public void process(Tuple.WindowedTuple<List<String>> tuple)
        {
          result = tuple;
          if (result.getValue().contains("bye")) {
            done = true;
          }
        }
      };
    }
  
    @Override
    public void populateDAG(DAG dag, Configuration conf)
    {
      Collector collector = new Collector();
  
      // Create a stream that reads from files in a local folder and output lines one by one to downstream.
      ApexStream<String> stream = StreamFactory.fromFolder("./src/test/resources/wordcount", name("textInput"))
  
          // Extract all the words from the input line of text.
          .flatMap(new Function.FlatMapFunction<String, String>()
          {
            @Override
            public Iterable<String> f(String input)
            {
              return Arrays.asList(input.split("[\\p{Punct}\\s]+"));
            }
          }, name("ExtractWords"))
  
          // Change the words to lower case, also shutdown the app when the word "bye" is detected.
          .map(new Function.MapFunction<String, String>()
          {
            @Override
            public String f(String input)
            {
              return input.toLowerCase();
            }
          }, name("ToLowerCase"));
  
      // Apply window and trigger option.
      stream.window(new WindowOption.GlobalWindow(),
          new TriggerOption().accumulatingFiredPanes().withEarlyFiringsAtEvery(Duration.standardSeconds(1)))
  
          // Remove the duplicate words and print out the result.
          .accumulate(new RemoveDuplicates<String>(), name("RemoveDuplicates"))
          .print(name("console"))
          .endWith(collector, collector.input)
          .populateDag(dag);
    }
  }
  