/// <exception cref="System.IO.IOException"/>
        public override void Initialize(InputSplit genericSplit, TaskAttemptContext context
                                        )
        {
            FileSplit     split = (FileSplit)genericSplit;
            Configuration job   = context.GetConfiguration();

            this.maxLineLength = job.GetInt(MaxLineLength, int.MaxValue);
            start = split.GetStart();
            end   = start + split.GetLength();
            Path file = split.GetPath();
            // open the file and seek to the start of the split
            FileSystem fs = file.GetFileSystem(job);

            fileIn = fs.Open(file);
            CompressionCodec codec = new CompressionCodecFactory(job).GetCodec(file);

            if (null != codec)
            {
                isCompressedInput = true;
                decompressor      = CodecPool.GetDecompressor(codec);
                if (codec is SplittableCompressionCodec)
                {
                    SplitCompressionInputStream cIn = ((SplittableCompressionCodec)codec).CreateInputStream
                                                          (fileIn, decompressor, start, end, SplittableCompressionCodec.READ_MODE.Byblock);
                    @in          = new CompressedSplitLineReader(cIn, job, this.recordDelimiterBytes);
                    start        = cIn.GetAdjustedStart();
                    end          = cIn.GetAdjustedEnd();
                    filePosition = cIn;
                }
                else
                {
                    @in = new SplitLineReader(codec.CreateInputStream(fileIn, decompressor), job, this
                                              .recordDelimiterBytes);
                    filePosition = fileIn;
                }
            }
            else
            {
                fileIn.Seek(start);
                @in = new UncompressedSplitLineReader(fileIn, job, this.recordDelimiterBytes, split
                                                      .GetLength());
                filePosition = fileIn;
            }
            // If this is not the first split, we always throw away first record
            // because we always (except the last split) read one extra line in
            // next() method.
            if (start != 0)
            {
                start += @in.ReadLine(new Text(), 0, MaxBytesToConsume(start));
            }
            this.pos = start;
        }
Beispiel #2
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        /// <exception cref="System.IO.IOException"/>
        public LineRecordReader(Configuration job, FileSplit split, byte[] recordDelimiter
                                )
        {
            this.maxLineLength = job.GetInt(LineRecordReader.MaxLineLength, int.MaxValue);
            start = split.GetStart();
            end   = start + split.GetLength();
            Path file = split.GetPath();

            compressionCodecs = new CompressionCodecFactory(job);
            codec             = compressionCodecs.GetCodec(file);
            // open the file and seek to the start of the split
            FileSystem fs = file.GetFileSystem(job);

            fileIn = fs.Open(file);
            if (IsCompressedInput())
            {
                decompressor = CodecPool.GetDecompressor(codec);
                if (codec is SplittableCompressionCodec)
                {
                    SplitCompressionInputStream cIn = ((SplittableCompressionCodec)codec).CreateInputStream
                                                          (fileIn, decompressor, start, end, SplittableCompressionCodec.READ_MODE.Byblock);
                    @in          = new CompressedSplitLineReader(cIn, job, recordDelimiter);
                    start        = cIn.GetAdjustedStart();
                    end          = cIn.GetAdjustedEnd();
                    filePosition = cIn;
                }
                else
                {
                    // take pos from compressed stream
                    @in = new SplitLineReader(codec.CreateInputStream(fileIn, decompressor), job, recordDelimiter
                                              );
                    filePosition = fileIn;
                }
            }
            else
            {
                fileIn.Seek(start);
                @in = new UncompressedSplitLineReader(fileIn, job, recordDelimiter, split.GetLength
                                                          ());
                filePosition = fileIn;
            }
            // If this is not the first split, we always throw away first record
            // because we always (except the last split) read one extra line in
            // next() method.
            if (start != 0)
            {
                start += @in.ReadLine(new Text(), 0, MaxBytesToConsume(start));
            }
            this.pos = start;
        }