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.carbondata.processing.loading.steps;
  
  import java.io.IOException;
  import java.util.Iterator;
  import java.util.List;
  import java.util.concurrent.Callable;
  import java.util.concurrent.ExecutionException;
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.Executors;
  import java.util.concurrent.Future;
  import java.util.concurrent.atomic.AtomicLong;
  
  import org.apache.carbondata.common.CarbonIterator;
  import org.apache.carbondata.core.datastore.row.CarbonRow;
  import org.apache.carbondata.core.util.CarbonProperties;
  import org.apache.carbondata.core.util.CarbonThreadFactory;
  import org.apache.carbondata.processing.loading.AbstractDataLoadProcessorStep;
  import org.apache.carbondata.processing.loading.CarbonDataLoadConfiguration;
  import org.apache.carbondata.processing.loading.DataField;
  import org.apache.carbondata.processing.loading.parser.RowParser;
  import org.apache.carbondata.processing.loading.parser.impl.RowParserImpl;
  import org.apache.carbondata.processing.loading.row.CarbonRowBatch;
  import org.apache.carbondata.processing.util.CarbonDataProcessorUtil;
  
  /**
   * It reads data from record reader and sends data to next step.
   */
  public class InputProcessorStepImpl extends AbstractDataLoadProcessorStep {
  
    private RowParser rowParser;
  
    private CarbonIterator<Object[]>[] inputIterators;
  
    // cores used in SDK writer, set by the user
    private short sdkWriterCores;
  
    /**
     * executor service to execute the query
     */
    public ExecutorService executorService;
    boolean isRawDataRequired = false;
    public InputProcessorStepImpl(CarbonDataLoadConfiguration configuration,
        CarbonIterator<Object[]>[] inputIterators) {
      super(configuration, null);
      this.inputIterators = inputIterators;
      this.sdkWriterCores = configuration.getWritingCoresCount();
    }
  
    @Override
    public DataField[] getOutput() {
      return configuration.getDataFields();
    }
  
    @Override
    public void initialize() throws IOException {
      super.initialize();
      rowParser = new RowParserImpl(getOutput(), configuration);
      executorService = Executors.newCachedThreadPool(new CarbonThreadFactory(
          "InputProcessorPool:" + configuration.getTableIdentifier().getCarbonTableIdentifier()
              .getTableName(), true));
      // if logger is enabled then raw data will be required.
      this.isRawDataRequired = CarbonDataProcessorUtil.isRawDataRequired(configuration);
    }
  
    @Override
    public Iterator<CarbonRowBatch>[] execute() {
      int batchSize = CarbonProperties.getInstance().getBatchSize();
      List<CarbonIterator<Object[]>>[] readerIterators =
          CarbonDataProcessorUtil.partitionInputReaderIterators(inputIterators, sdkWriterCores);
      Iterator<CarbonRowBatch>[] outIterators = new Iterator[readerIterators.length];
      for (int i = 0; i < outIterators.length; i++) {
        outIterators[i] =
            new InputProcessorIterator(readerIterators[i], rowParser, batchSize,
                configuration.isPreFetch(), executorService, rowCounter, isRawDataRequired);
      }
      return outIterators;
    }
  
    @Override
    public void close() {
      if (!closed) {
        super.close();
        if (null != executorService) {
          executorService.shutdownNow();
        }
        for (CarbonIterator inputIterator : inputIterators) {
          inputIterator.close();
        }
      }
    }
  
    @Override
    protected String getStepName() {
      return "Input Processor";
    }
  
    /**
     * This iterator wraps the list of iterators and it starts iterating the each
     * iterator of the list one by one. It also parse the data while iterating it.
     */
    public static class InputProcessorIterator extends CarbonIterator<CarbonRowBatch> {
  
      private List<CarbonIterator<Object[]>> inputIterators;
  
      private CarbonIterator<Object[]> currentIterator;
  
      private int counter;
  
      private int batchSize;
  
      private RowParser rowParser;
  
      private Future<CarbonRowBatch> future;
  
      private ExecutorService executorService;
  
      private boolean nextBatch;
  
      private boolean firstTime;
  
      private boolean preFetch;
  
      private AtomicLong rowCounter;
  
      private boolean isRawDataRequired = false;
  
      public InputProcessorIterator(List<CarbonIterator<Object[]>> inputIterators,
          RowParser rowParser, int batchSize, boolean preFetch, ExecutorService executorService,
          AtomicLong rowCounter, boolean isRawDataRequired) {
        this.inputIterators = inputIterators;
        this.batchSize = batchSize;
        this.rowParser = rowParser;
        this.counter = 0;
        // Get the first iterator from the list.
        currentIterator = inputIterators.get(counter++);
        this.executorService = executorService;
        this.rowCounter = rowCounter;
        this.preFetch = preFetch;
        this.nextBatch = false;
        this.firstTime = true;
        this.isRawDataRequired = isRawDataRequired;
      }
  
      @Override
      public boolean hasNext() {
        return nextBatch || internalHasNext();
      }
  
      private boolean internalHasNext() {
        if (firstTime) {
          firstTime = false;
          currentIterator.initialize();
        }
        boolean hasNext = currentIterator.hasNext();
        // If iterator is finished then check for next iterator.
        if (!hasNext) {
          currentIterator.close();
          // Check next iterator is available in the list.
          if (counter < inputIterators.size()) {
            // Get the next iterator from the list.
            currentIterator = inputIterators.get(counter++);
            // Initialize the new iterator
            currentIterator.initialize();
            hasNext = internalHasNext();
          }
        }
        return hasNext;
      }
  
      @Override
      public CarbonRowBatch next() {
        if (preFetch) {
          return getCarbonRowBatchWithPreFetch();
        } else {
          return getBatch();
        }
      }
  
      private CarbonRowBatch getCarbonRowBatchWithPreFetch() {
        CarbonRowBatch result = null;
        if (future == null) {
          future = getCarbonRowBatch();
        }
        try {
          result = future.get();
        } catch (InterruptedException e) {
          throw new RuntimeException(e);
        } catch (ExecutionException e) {
          throw new RuntimeException(e);
        }
        nextBatch = false;
        if (hasNext()) {
          nextBatch = true;
          future = getCarbonRowBatch();
        }
  
        return result;
      }
  
      private Future<CarbonRowBatch> getCarbonRowBatch() {
        return executorService.submit(new Callable<CarbonRowBatch>() {
          @Override
          public CarbonRowBatch call() {
            return getBatch();
  
          }
        });
      }
  
      private CarbonRowBatch getBatch() {
        // Create batch and fill it.
        CarbonRowBatch carbonRowBatch = new CarbonRowBatch(batchSize);
        int count = 0;
        if (isRawDataRequired) {
          while (internalHasNext() && count < batchSize) {
            Object[] rawRow = currentIterator.next();
            carbonRowBatch.addRow(new CarbonRow(rowParser.parseRow(rawRow), rawRow));
            count++;
          }
        } else {
          while (internalHasNext() && count < batchSize) {
            carbonRowBatch.addRow(new CarbonRow(rowParser.parseRow(currentIterator.next())));
            count++;
          }
        }
        rowCounter.getAndAdd(carbonRowBatch.getSize());
        return carbonRowBatch;
      }
    }
  
  }
  