/// <summary>
/// Method to open an sbn index file
/// </summary>
/// <param name="sbnFilename">The sbn index filename></param>
/// <returns>An sbn index query structure</returns>
public static SbnQueryOnlyTree Open(string sbnFilename)
{
if (string.IsNullOrEmpty(sbnFilename))
{
throw new ArgumentNullException(sbnFilename);
}
if (!File.Exists(sbnFilename))
{
throw new FileNotFoundException("File not found", sbnFilename);
}
var sbxFilename = Path.ChangeExtension(sbnFilename, "sbx");
if (!File.Exists(sbxFilename))
{
throw new FileNotFoundException("File not found", sbxFilename);
}
var res = new SbnQueryOnlyTree(sbnFilename, sbxFilename);
var sbxHeader = new SbnHeader();
sbxHeader.Read(new BinaryReader(res._sbxStream));
if (res._sbnHeader.NumRecords != sbxHeader.NumRecords)
{
throw new SbnException("Sbn and Sbx do not serve the same number of features!");
}
return(res);
}
/// <summary>
/// Creates the tree reading data from the <paramref name="reader"/>
/// </summary>
/// <param name="reader">The reader to use</param>
private SbnTree(BinaryReader reader)
{
Monitor.Enter(_syncRoot);
_header = new SbnHeader();
_header.Read(reader);
BuildTree(_header.NumRecords);
if (BinaryIOExtensions.ReadUInt32BE(reader) != 1)
{
throw new SbnException("Invalid format, expecting 1");
}
var maxNodeId = BinaryIOExtensions.ReadInt32BE(reader) / 4;
var ms = new MemoryStream(reader.ReadBytes(maxNodeId * 8));
using (var msReader = new BinaryReader(ms))
{
var indexNodeId = 1;
while (msReader.BaseStream.Position < msReader.BaseStream.Length)
{
var nid = BinaryIOExtensions.ReadInt32BE(msReader);
var featureCount = BinaryIOExtensions.ReadInt32BE(msReader);
if (nid > 1)
{
var node = Nodes[indexNodeId];
while (node.FeatureCount < featureCount)
{
var bin = new SbnBin();
bin.Read(reader);
node.AddBin(bin, true);
}
Debug.Assert(node.VerifyBins());
}
indexNodeId++;
}
}
//Gather all feature ids
GatherFids();
//Assertions
Debug.Assert(reader.BaseStream.Position == reader.BaseStream.Length);
Debug.Assert(_featureIds.Count == _header.NumRecords);
Monitor.Exit(_syncRoot);
}
/// <summary>
/// Creates an istance of this class
/// </summary>
/// <param name="sbnFilename"></param>
/// <param name="sbxFilename"></param>
private SbnQueryOnlyTree(string sbnFilename, string sbxFilename)
{
_sbnStream = new FileStream(sbnFilename, FileMode.Open, FileAccess.Read, FileShare.Read, 8192);
_sbnHeader = new SbnHeader();
var sbnReader = new BinaryReader(_sbnStream);
_sbnHeader.Read(sbnReader);
_sbnBinIndex = SbnBinIndex.Read(sbnReader);
_sbxStream = new FileStream(sbxFilename, FileMode.Open, FileAccess.Read, FileShare.Read, 8192);
FirstLeafNodeId = (int)Math.Pow(2, GetNumberOfLevels(_sbnHeader.NumRecords) - 1);
MaxCacheLevel = DefaultMaxCacheLevel;
SbnQueryOnlyNode.CreateRoot(this);
_sbxStream.Position = 0;
}
/// <summary>
/// Method to describe the tree's content
/// </summary>
/// <param name="sbnTree"></param>
/// <param name="writer"></param>
public static void SbnToText(string sbnTree, TextWriter writer)
{
using (var br = new BinaryReader(File.OpenRead(sbnTree)))
{
// header
var header = new SbnHeader();
header.Read(br);
writer.WriteLine(header.ToString());
// Bin header
writer.WriteLine("[BinHeader]");
if (BinaryIOExtensions.ReadUInt32BE(br) != 1)
{
throw new SbnException("Invalid format, expecting 1");
}
var maxNodeId = BinaryIOExtensions.ReadInt32BE(br) / 4;
writer.WriteLine("#1, {0} => MaxNodeId = {1}", maxNodeId * 4, maxNodeId);
var ms = new MemoryStream(br.ReadBytes(maxNodeId * 8));
using (var msReader = new BinaryReader(ms))
{
var index = 2;
while (msReader.BaseStream.Position < msReader.BaseStream.Length)
{
writer.WriteLine("#{2}, Index {0}, NumFeatures={1}",
BinaryIOExtensions.ReadInt32BE(msReader), BinaryIOExtensions.ReadInt32BE(msReader), index++);
}
}
writer.WriteLine("[Bins]");
while (br.BaseStream.Position < br.BaseStream.Length)
{
var bin = new SbnBin();
var binId = bin.Read(br);
writer.Write("[SbnBin {0}: {1}]\n", binId, bin.NumFeatures);
for (var i = 0; i < bin.NumFeatures; i++)
{
writer.WriteLine(" " + bin[i]);
}
}
}
writer.Flush();
}