private static WAHBitArray DoBitOperation(WAHBitArray bits, Cache c, Cache.OPERATION op)
{
if (bits != null)
{
bits = c.Op(bits, op);
}
else
{
bits = c.GetBitmap();
bits = op == Cache.OPERATION.ANDNOT ? bits.Not() : bits;
}
return(bits);
}
public IndexResult UpdateExistingIndex(int recnum, string text)
{
Log("UpdateExistingIndex started");
LogIndex();
Log(string.Format("text size = {0}", text.Length));
Dictionary <string, int> wordFrequencies = GenerateWordFreq(text);
Log(string.Format("word count = {0}", wordFrequencies.Count));
var result = new IndexResult {
DocNumber = recnum
};
using (var bmp = CreateBitmapStream())
{
foreach (KeyValuePair <string, Cache> vc in _index)
{
string indexedWord = vc.Key;
Cache cache = vc.Value;
LoadCacheIfNotLoaded(cache, bmp);
bool isWordIndexed = cache.GetBitmap().Get(recnum);
bool isWordInText = wordFrequencies.ContainsKey(indexedWord);
if (isWordIndexed && isWordInText)
{
wordFrequencies.Remove(indexedWord);
}
else if (isWordIndexed)
{
result.WordsRemoved.Add(indexedWord);
cache.SetBit(recnum, false);
}
else if (isWordInText)
{
result.WordsAdded.Add(indexedWord, wordFrequencies[indexedWord]);
wordFrequencies.Remove(indexedWord);
cache.SetBit(recnum, true);
}
}
}
foreach (var wordFrequency in wordFrequencies)
{
result.WordsAdded.Add(wordFrequency.Key, wordFrequency.Value);
var cache = new Cache {
isLoaded = true
};
cache.SetBit(recnum, true);
_index.Add(wordFrequency.Key, cache);
}
LogIndex();
Log("UpdateExistingIndex ended");
return(result);
}
public IndexData GetExistingIndex(int recnum)
{
LogIndex();
using (var bmp = CreateBitmapStream())
{
var words = new List <string>();
foreach (KeyValuePair <string, Cache> vc in _index)
{
string indexedWord = vc.Key;
Cache cache = vc.Value;
LoadCacheIfNotLoaded(cache, bmp);
bool isWordIndexed = cache.GetBitmap().Get(recnum);
if (isWordIndexed)
{
words.Add(indexedWord);
}
}
return(new IndexData
{
DocNumber = recnum,
Words = words
});
}
}
