public TrieIndexHeader Deserialize(Stream stream)
{
var header = new TrieIndexHeader();
var properties = GetProperties(header);
using (var reader = new StreamReader(stream, Encoding.UTF8))
{
while (reader.Peek() > -1)
{
string[] keyValue = reader.ReadLine().Split(KeyValueSeperator);
string key = keyValue[0];
var property = properties.SingleOrDefault(f => f.Name == key);
if (property == null)
{
throw new Exception("Property not found");
}
object propertyValue = DeserializeValue(keyValue[1], property.PropertyType);
property.SetValue(header, propertyValue);
}
}
return(header);
}
public void get_character_index_must_be_null()
{
var header = new TrieIndexHeader();
var characterIndex = TrieIndexHeaderCharacterReader.Instance.GetCharacterIndex(header, 'a');
Assert.AreEqual(null, characterIndex);
}
internal long[] GetChildrenPositionsFromNode(BinaryReader binaryReader, TrieIndexHeader Header, long parentPosition)
{
int childrenOffset = ReadChildrenOffset(parentPosition);
if (childrenOffset == 0) // -1 equals to non-childed parent
{
return(null);
}
bool[] childrenFlags = ReadChildrenFlags(parentPosition);
int childrenCount = GetFlaggedCount(childrenFlags, true);
long[] childrenPositions = new long[childrenCount];
for (int i = 0; i < childrenCount; i++)
{
long targetPosition = parentPosition +
childrenOffset +
(i * Header.LENGTH_OF_STRUCT);
childrenPositions[i] = targetPosition;
}
return(childrenPositions);
}
public void character_list_must_be_initialized_when_new_instance_was_created()
{
var header = new TrieIndexHeader();
Assert.IsNotNull(header);
Assert.IsNotNull(header.CharacterList);
Assert.AreEqual(0, header.CharacterList.Count);
}
private TrieIndexHeaderBuilder SortCharacterList(ref TrieIndexHeader header)
{
if (header == null || _characterList == null)
{
throw new ArgumentNullException("header");
}
_characterList.Sort(new TrieCharacterComparer());
return(this);
}
public IndexBuilder(Stream headerStream, Stream indexStream, Stream tailStream)
{
_headerStream = headerStream;
_indexStream = indexStream;
_tailStream = tailStream;
_header = new TrieIndexHeader();
_trie = new Trie();
_keywords = new HashSet <string>();
_keywordDictionary = new Dictionary <string, uint>();
}
/// <summary>
/// Gets the index of the character.
/// Returns null when charcacter is not found.
/// </summary>
/// <returns>The character index.</returns>
/// <param name="c">C.</param>
internal ushort?GetCharacterIndex(TrieIndexHeader header, char c)
{
InitCharacterCache(header);
if (!_characterIndexDictionary[header].ContainsKey(c))
{
return(null);
}
return(_characterIndexDictionary[header][c]);
}
internal TrieIndexHeader Build()
{
var header = new TrieIndexHeader();
header.CharacterList = _characterList;
SortCharacterList(ref header);
CalculateMetrics(ref header);
return(header);
}
public static int CreateIndexFile(this TrieBinaryReader instance, TrieIndexHeader header, TrieNode node, string path, int readBufferSizeInBytes)
{
Stream stream = new FileStream(
path,
FileMode.OpenOrCreate,
FileAccess.Write,
FileShare.None,
readBufferSizeInBytes,
FileOptions.RandomAccess
);
return(TrieIndexSerializer.Serialize(node, header, stream));
}
public static void CreateHeaderFile(this TrieIndexHeader header, string path)
{
var serializer = new TrieIndexHeaderSerializer();
using (Stream stream = new FileStream(
path,
FileMode.OpenOrCreate,
FileAccess.Write,
FileShare.None
))
{
serializer.Serialize(stream, header);
}
}
internal ICollection <UInt16> GetFlagedCharCodes(BitArray bitArray, TrieIndexHeader Header, bool flag)
{
ICollection <UInt16> charCodeList = new List <UInt16>(Header.COUNT_OF_CHILDREN_FLAGS_IN_BYTES); // TODO: use different constant
for (UInt16 i = 0; i < bitArray.Length; i++)
{
if (bitArray.Get(i) == flag)
{
charCodeList.Add(i); // TODO: use mapping
}
}
return(charCodeList);
}
public static void CreateHeaderFile(this TrieIndexHeader header, string path)
{
Stream stream = new FileStream(
path,
FileMode.OpenOrCreate,
FileAccess.Write,
FileShare.None
);
TrieSerializer.SerializeHeaderWithJsonSerializer(stream, header);
//stream.Close();
stream.Dispose();
stream = null;
}
internal ICollection <char> GetFlagedChars(BitArray bitArray, TrieIndexHeader Header, bool flag)
{
ICollection <char> charList = new List <char>();
ICollection <UInt16> charCodes = GetFlagedCharCodes(bitArray, Header, flag);
if (charCodes != null)
{
foreach (UInt16 item in charCodes)
{
char currentCharacter = TrieIndexHeaderCharacterReader.Instance.GetCharacterAtIndex(Header, item);
charList.Add(currentCharacter);
}
}
return(charList);
}
private void ReorderTrieAndLoadHeader(TrieNode rootNode)
{
TrieIndexHeader header = new TrieIndexHeader();
Queue <TrieNode> indexerQueue = new Queue <TrieNode>();
indexerQueue.Enqueue(rootNode);
int order = 0;
var builder = new TrieIndexHeaderBuilder();
TrieNode currentNode = null;
while (indexerQueue.Count > 0)
{
currentNode = indexerQueue.Dequeue();
if (currentNode == null)
{
throw new ArgumentNullException("Root node is null");
}
currentNode.Order = order;
builder.AddChar(currentNode.Character);
// set parent's children index when current node's child
// index not equal to zero and current index is not the root
if (currentNode.Parent != null && currentNode.ChildIndex == 0)
{
currentNode.Parent.ChildrenCount = (currentNode.Order - currentNode.Parent.Order);
}
if (currentNode.Children != null)
{
int childIndex = 0;
foreach (var childNode in currentNode.Children)
{
childNode.Value.ChildIndex = childIndex++;
indexerQueue.Enqueue(childNode.Value);
}
}
++order;
}
_header = builder.Build();
}
public SearchResult Search(SearchOptions options)
{
if (options == null)
{
throw new ArgumentException("options");
}
if (_header == null)
{
_header = GetHeader();
}
var reader = CreateTrieBinaryReader();
var node = reader.SearchLastNode(0, options.Term);
return(CreateResultFromNode(reader, node, options.Term, options));
}
public void Serialize(Stream stream, TrieIndexHeader header)
{
var properties = GetProperties(header);
using (var writer = new StreamWriter(stream, Encoding.UTF8))
{
foreach (var property in properties)
{
writer.Write(property.Name);
writer.Write(KeyValueSeperator);
var propertyValue = property.GetValue(header);
SerializePropertyValue(propertyValue, property.PropertyType, writer);
writer.Write(Environment.NewLine);
}
}
}
internal override TrieIndexHeader GetHeader()
{
// double checked initialization
if (!_headerDictionary.ContainsKey(_headerFileName))
{
lock (_lockObject)
{
if (!_headerDictionary.ContainsKey(_headerFileName))
{
var currentHeader = TrieNodeHelperFileSystemExtensions.ReadHeaderFile(_headerFileName);
_headerDictionary.Add(_headerFileName, currentHeader);
}
}
}
TrieIndexHeader header = _headerDictionary[_headerFileName];
return(header);
}
private void CalculateMetrics(ref TrieIndexHeader header)
{
// Set structural based properties
header.COUNT_OF_CHARSET = _characterList.Count;
header.COUNT_OF_CHILDREN_FLAGS = header.COUNT_OF_CHARSET / 8 + (header.COUNT_OF_CHARSET % 8 == 0 ? 0 : 1);
header.COUNT_OF_CHILDREN_FLAGS_IN_BYTES = header.COUNT_OF_CHARSET / 32 + (header.COUNT_OF_CHARSET % 32 == 0 ? 0 : 1);
header.COUNT_OF_CHILDREN_FLAGS_BIT_ARRAY_IN_BYTES = header.COUNT_OF_CHILDREN_FLAGS_IN_BYTES * 4;
header.LENGTH_OF_CHILDREN_FLAGS = header.COUNT_OF_CHARACTER_IN_BYTES + // 2
header.COUNT_TERMINAL_SIZE_IN_BYTES; // 1;
header.LENGTH_OF_CHILDREN_OFFSET = header.LENGTH_OF_CHILDREN_FLAGS + // 2
header.COUNT_OF_CHILDREN_FLAGS_BIT_ARRAY_IN_BYTES;
header.LENGHT_OF_TEXT_FILE_START_POSITION_IN_BYTES = header.LENGTH_OF_CHILDREN_OFFSET +
header.COUNT_OF_TEXT_FILE_START_POSITION_IN_BYTES;
header.LENGTH_OF_STRUCT = header.LENGHT_OF_TEXT_FILE_START_POSITION_IN_BYTES +
header.COUNT_OF_CHILDREN_OFFSET_IN_BYTES;
}
internal void InitCharacterCache(TrieIndexHeader header)
{
if (!_isCharacterIndexCacheInitialized.ContainsKey(header))
{
lock (this)
{
if (!_isCharacterIndexCacheInitialized.ContainsKey(header))
{
_isCharacterIndexCacheInitialized.Add(header, true);
_characterIndexDictionary.Add(header, new Dictionary <char, UInt16>());
for (UInt16 i = 0; i < header.CharacterList.Count; i++)
{
if (header.CharacterList[i] != '\0')
{
_characterIndexDictionary[header].Add(header.CharacterList[i], i);
}
}
}
}
}
}
internal char GetCharacterAtIndex(TrieIndexHeader header, UInt16 index)
{
InitCharacterCache(header);
return(header.CharacterList[index]);
}
public TrieBinaryReader(BinaryReader binaryReader, TrieIndexHeader header)
{
_binaryReader = binaryReader;
_header = header;
}
private IEnumerable <PropertyInfo> GetProperties(TrieIndexHeader header)
{
return(header.GetType().GetRuntimeProperties());
}
/// <summary>
///
/// </summary>
/// <param name="rootNode"></param>
/// <param name="trieIndexHeader"></param>
/// <param name="index"></param>
/// <remarks>Don't forget to dispose stream</remarks>
/// <returns></returns>
public static int Serialize(TrieNode rootNode, TrieIndexHeader trieIndexHeader, Stream index)
{
int processedNodeCount = 0;
Queue <TrieNode> serializerQueue = new Queue <TrieNode>();
serializerQueue.Enqueue(rootNode);
TrieNode currentNode = null;
BinaryWriter binaryWriter = new BinaryWriter(index);
while (serializerQueue.Count > 0)
{
currentNode = serializerQueue.Dequeue();
if (currentNode == null)
{
throw new InvalidDataException(string.Format("Value cannot be null ", processedNodeCount));
}
long currentPositionOfStream = binaryWriter.BaseStream.Position;
// write character
//bw.Write(Encoding.Unicode.GetBytes(node.Character.ToString()));
UInt16?characterIndex = TrieIndexHeaderCharacterReader.Instance.GetCharacterIndex(trieIndexHeader, currentNode.Character);
if (characterIndex != null && characterIndex.HasValue)
{
binaryWriter.Write(characterIndex.Value);
}
else
{
binaryWriter.Write(Convert.ToUInt16(0)); // Its root
}
binaryWriter.Write(currentNode.IsTerminal);
// write children flags
// convert 512 bool value to 64 byte value for efficient storage
BitArray baChildren = new BitArray(trieIndexHeader.COUNT_OF_CHARSET);
if (currentNode.Children != null)
{
foreach (var item in currentNode.Children)
{
UInt16?itemIndex = TrieIndexHeaderCharacterReader.Instance.GetCharacterIndex(trieIndexHeader, item.Key);
baChildren.Set(itemIndex.Value, true);
}
}
int[] childrenFlags = new int[trieIndexHeader.COUNT_OF_CHILDREN_FLAGS_IN_BYTES];
BitArrayHelper.CopyToInt32Array(baChildren, childrenFlags, 0);
for (int i = 0; i < childrenFlags.Length; i++)
{
binaryWriter.Write(childrenFlags[i]);
}
// write children offset
binaryWriter.Write(currentNode.ChildrenCount * trieIndexHeader.LENGTH_OF_STRUCT);
// todo:position of text file
if (currentNode.PositionOnTextFile.HasValue)
{
binaryWriter.Write((uint)currentNode.PositionOnTextFile.Value);
}
else
{
binaryWriter.Write((uint)0);
}
if (currentNode.Children != null)
{
foreach (var childNode in currentNode.Children)
{
serializerQueue.Enqueue(childNode.Value);
}
}
++processedNodeCount;
}
return(processedNodeCount);
}
