public List<byte> processBytes(PADIMapNoReduce.Pair<long, long> byteInterval, string filePath)
{
//System.Console.WriteLine("Received request for bytes from " + byteInterval.First + " to " + byteInterval.Second);
List<byte> result = new List<byte>();
long fileSize = new FileInfo(filePath).Length;
if (byteInterval.First == 0 && byteInterval.Second == fileSize)
{
return new List<byte>(readByteInterval(byteInterval, filePath));
}
else
{
if (byteInterval.First == 0) //FirstSplit
{
long lastByte;
result.AddRange(new List<byte>(readByteInterval(byteInterval, filePath)));
if (getCharFromBytePosition(result[result.Count - 1], filePath) != '\n')
{
result.AddRange(new List<byte>(readUntilNewLine(byteInterval.Second + 1, filePath, out lastByte)));
}
}
else if (byteInterval.Second == fileSize) //lastSplit
{
long lastByte = byteInterval.First;
char lastChar = getCharFromBytePosition(byteInterval.First - 1, filePath);
if (lastChar != '\n')
{
readUntilNewLine(byteInterval.First, filePath, out lastByte);
lastByte++;
}
if (lastByte >= byteInterval.Second)
{
return result;
}
result.AddRange(readByteInterval(new PADIMapNoReduce.Pair<long, long>(lastByte, fileSize), filePath));
}
else //middle split
{
long lastByte = byteInterval.First;
char lastChar = getCharFromBytePosition(byteInterval.First - 1, filePath);
if (lastChar != '\n')
{
readUntilNewLine(byteInterval.First, filePath, out lastByte);
lastByte++;
}
if (lastByte > byteInterval.Second)
{
return result;
}
result.AddRange(readByteInterval(new PADIMapNoReduce.Pair<long, long>(lastByte, byteInterval.Second), filePath));
if (getCharFromBytePosition(result[result.Count - 1], filePath) != '\n')
{
result.AddRange(readUntilNewLine(byteInterval.Second + 1, filePath, out lastByte));
}
}
}
return result;
}
public FileSplit(int i, PADIMapNoReduce.Pair<long, long> pair)
{
this.splitId = i;
this.pair = pair;
}
//Returns the string that corresponds to the byteInterval received
private byte[] readByteInterval(PADIMapNoReduce.Pair<long, long> byteInterval, string filePath)
{
if (byteInterval.First > byteInterval.Second)
{
return new byte[0];
}
byte[] bytes = new byte[byteInterval.Second - byteInterval.First + 1];
using (BinaryReader reader = new BinaryReader(new BufferedStream(new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read))))
{
reader.BaseStream.Seek(byteInterval.First, SeekOrigin.Begin);
reader.Read(bytes, 0, bytes.Length);
}
return bytes;
}
