/// <summary>
/// The method sorts the source file and saves the result to the destination file.
/// </summary>
public void Sort(string sourceFile, string destinationFile)
{
// Validate arguments
if (string.IsNullOrWhiteSpace(sourceFile))
{
throw new ArgumentException("sourceFile cannot be empty.");
}
if (string.IsNullOrWhiteSpace(destinationFile))
{
throw new ArgumentException("destinationFile cannot be empty.");
}
// Initialise paramets
var fileWorker = new XFileWorker(destinationFile);
var blockLimit = (int)(getAvailableMemory() * 0.3 / Environment.ProcessorCount);
var blockCapacity = blockLimit / DefaultXRowLength;
long currentblockSize = 0;
XRow row = null;
var rows = new List <XRow>(blockCapacity);
// Read source file
using (var file = File.OpenText(sourceFile))
{
while ((row = file.ReadXRow()) != null)
{
currentblockSize += row.String.Length;
rows.Add(row);
// Split tha data on blocks
if (currentblockSize > blockLimit)
{
// Sort block and save it to a temporary file
fileWorker.SortAndSave(rows);
// Clean lines buffer
currentblockSize = 0;
rows = new List <XRow>(blockCapacity);
// Start merging the chanks to load CPU and I/O in parallel
fileWorker.Merge();
}
}
}
// Sort and save the last block
if (rows.Count > 0)
{
fileWorker.SortAndSave(rows, true);
}
// Merge all blocks
fileWorker.Merge(true);
}
private void merge(string source1, string source2, string destination)
{
long s1 = 0;
long s2 = 0;
using (var f1 = File.OpenText(source1))
{
XRow l1 = f1.ReadXRow();
s1 += l1.String.Length;
using (var f2 = File.OpenText(source2))
{
XRow l2 = f2.ReadXRow();
s2 += l2.String.Length;
using (var d = new StreamWriter(destination, false, Encoding.Default))
{
while (l1 != null || l2 != null)
{
if (l1 == null)
{
d.WriteLine(l2);
l2 = f2.ReadXRow();
s2 += l2 != null ? l2.String.Length : 0;
continue;
}
if (l2 == null)
{
d.WriteLine(l1);
l1 = f1.ReadXRow();
s1 += l1 != null ? l1.String.Length : 0;
continue;
}
if (l1.CompareTo(l2) <= 0)
{
d.WriteLine(l1);
l1 = f1.ReadXRow();
s1 += l1 != null ? l1.String.Length : 0;
continue;
}
d.WriteLine(l2);
l2 = f2.ReadXRow();
s2 += l2 != null ? l2.String.Length : 0;
}
d.Close();
}
}
}
var ex = false;
using (var t1 = File.Open(source1, FileMode.Open))
{
using (var t2 = File.Open(source2, FileMode.Open))
{
using (var t3 = File.Open(destination, FileMode.Open))
{
if (t3.Length != (t1.Length + t2.Length))
{
ex = true;
}
}
}
}
if (ex)
{
ex = false;
}
File.Delete(source1);
File.Delete(source2);
}
