MDSHiveDirectVectorizedReader.java 文件源码

@Override
public boolean next( final NullWritable key, final VectorizedRowBatch outputBatch ) throws IOException {
  outputBatch.reset();
  setting.setPartitionValues( outputBatch );

  if( indexSize <= currentIndex ){
    if( ! currentReader.hasNext() ){
      updateCounter( currentReader.getReadStats() );
      outputBatch.endOfFile = true;
      isEnd = true;
      return false;
    }
    while( ! setSpread() ){
      if( ! currentReader.hasNext() ){
        updateCounter( currentReader.getReadStats() );
        outputBatch.endOfFile = true;
        isEnd = true;
        return false;
      }
    }
  }
  int maxSize = outputBatch.getMaxSize();
  if( indexSize < currentIndex + maxSize ){
    maxSize = indexSize - currentIndex;
  }

  for( int colIndex : needColumnIds ){
    assignors[colIndex].setColumnVector( outputBatch.cols[colIndex] , currentIndexList , currentIndex , maxSize );
  }
  outputBatch.size = maxSize;

  currentIndex += maxSize;
  if( indexSize <= currentIndex && ! currentReader.hasNext() ){
    outputBatch.endOfFile = true;
  }

  return outputBatch.size > 0;
}