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.sdk.file;
  
  import java.io.File;
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.concurrent.Callable;
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.Executors;
  import java.util.concurrent.Future;
  import java.util.concurrent.TimeUnit;
  
  import org.apache.carbondata.core.metadata.datatype.DataTypes;
  import org.apache.carbondata.core.metadata.datatype.Field;
  
  import org.apache.commons.io.FileUtils;
  import org.apache.hadoop.mapreduce.InputSplit;
  import org.junit.After;
  import org.junit.Assert;
  import org.junit.Before;
  import org.junit.Test;
  
  /**
   * multi-thread Test suite for {@link CarbonReader}
   */
  public class MultithreadSDKBlockletReaderTest {
  
    private static final String dataDir = "./testReadFiles";
  
    @Before @After public void cleanTestData() {
      try {
        FileUtils.deleteDirectory(new File(dataDir));
      } catch (Exception e) {
        e.printStackTrace();
        Assert.fail(e.getMessage());
      }
    }
  
    private void writeDataMultipleFiles(int numFiles, long numRowsPerFile) {
      Field[] fields = new Field[2];
      fields[0] = new Field("stringField", DataTypes.STRING);
      fields[1] = new Field("intField", DataTypes.INT);
  
      for (int numFile = 0; numFile < numFiles; ++numFile) {
        CarbonWriterBuilder builder =
            CarbonWriter.builder().outputPath(dataDir).withCsvInput(new Schema(fields))
                .withBlockletSize(1).withBlockletSize(2).writtenBy("ConcurrentSdkReaderTest");
        try {
          CarbonWriter writer = builder.build();
  
          for (long i = 0; i < numRowsPerFile; ++i) {
            writer.write(new String[] { "robot_" + i, String.valueOf(i) });
          }
          writer.close();
        } catch (Exception e) {
          e.printStackTrace();
          Assert.fail(e.getMessage());
        }
      }
    }
  
    @Test public void testReadParallely() throws IOException, InterruptedException {
      int numFiles = 2;
      int numRowsPerFile = 1000000;
      short numThreads;
      writeDataMultipleFiles(numFiles, numRowsPerFile);
      long count;
  
      InputSplit[] splits = CarbonReader.builder(dataDir).getSplits(true);
      Assert.assertEquals(splits.length, 8);
      numThreads = (short) splits.length;
      // Concurrent Reading
      ExecutorService executorService = Executors.newFixedThreadPool(numThreads);
      try {
        try {
          List<ReadLogic> tasks = new ArrayList<>();
          List<Future<Long>> results;
          count = 0;
          for (InputSplit split : splits) {
            tasks.add(new ReadLogic(split));
          }
          long start = System.currentTimeMillis();
          results = executorService.invokeAll(tasks);
          for (Future result_i : results) {
            count += (long) result_i.get();
          }
          long end = System.currentTimeMillis();
          System.out.println("[Parallel read] Time: " + (end - start) + " ms");
          Assert.assertEquals(numFiles * numRowsPerFile, count);
        } catch (Exception e) {
          e.printStackTrace();
          Assert.fail(e.getMessage());
        }
      } catch (Exception e) {
        e.printStackTrace();
        Assert.fail(e.getMessage());
      } finally {
        executorService.shutdown();
        executorService.awaitTermination(10, TimeUnit.MINUTES);
      }
    }
  
    class ReadLogic implements Callable<Long> {
      InputSplit split;
  
      ReadLogic(InputSplit split) {
        this.split = split;
      }
  
      @Override
      public Long call() throws IOException, InterruptedException {
        long count = 0;
        CarbonReader reader = CarbonReader.builder(split).build();
        try {
          while (reader.hasNext()) {
            reader.readNextRow();
            count += 1;
          }
        } catch (Exception e) {
          e.printStackTrace();
          Assert.fail(e.getMessage());
        } finally {
          reader.close();
        }
        return count;
      }
    }
  
  }