Пример #1
0
            /// <summary>Constructor</summary>
            /// <param name="fin">FS input stream.</param>
            /// <param name="fileLength">Length of the corresponding file</param>
            /// <exception cref="System.IO.IOException"/>
            public Reader(FSDataInputStream fin, long fileLength, Configuration conf)
            {
                this.@in  = fin;
                this.conf = conf;
                // move the cursor to the beginning of the tail, containing: offset to the
                // meta block index, version and magic
                fin.Seek(fileLength - BCFile.Magic.Size() - Utils.Version.Size() - long.Size / byte
                         .Size);
                long offsetIndexMeta = fin.ReadLong();

                version = new Utils.Version(fin);
                BCFile.Magic.ReadAndVerify(fin);
                if (!version.CompatibleWith(BCFile.ApiVersion))
                {
                    throw new RuntimeException("Incompatible BCFile fileBCFileVersion.");
                }
                // read meta index
                fin.Seek(offsetIndexMeta);
                metaIndex = new BCFile.MetaIndex(fin);
                // read data:BCFile.index, the data block index
                BCFile.Reader.BlockReader blockR = GetMetaBlock(BCFile.DataIndex.BlockName);
                try
                {
                    dataIndex = new BCFile.DataIndex(blockR);
                }
                finally
                {
                    blockR.Close();
                }
            }
Пример #2
0
 /// <summary>Constructor</summary>
 /// <param name="fout">FS output stream.</param>
 /// <param name="compressionName">
 /// Name of the compression algorithm, which will be used for all
 /// data blocks.
 /// </param>
 /// <exception cref="System.IO.IOException"/>
 /// <seealso cref="Compression.GetSupportedAlgorithms()"/>
 public Writer(FSDataOutputStream fout, string compressionName, Configuration conf
               )
 {
     if (fout.GetPos() != 0)
     {
         throw new IOException("Output file not at zero offset.");
     }
     this.@out      = fout;
     this.conf      = conf;
     dataIndex      = new BCFile.DataIndex(compressionName);
     metaIndex      = new BCFile.MetaIndex();
     fsOutputBuffer = new BytesWritable();
     BCFile.Magic.Write(fout);
 }