public override int GetOrdinal(FacetLabel cp)
{
EnsureOpen();
if (cp.Length == 0)
{
return(ROOT_ORDINAL);
}
// First try to find the answer in the LRU cache:
// LUCENENET: Lock was removed here because the underlying cache is thread-safe,
// and removing the lock seems to make the performance better.
Int32Class res = ordinalCache.Get(cp);
if (res != null)
{
if ((int)res.Value < indexReader.MaxDoc)
{
// Since the cache is shared with DTR instances allocated from
// doOpenIfChanged, we need to ensure that the ordinal is one that
// this DTR instance recognizes.
return((int)res.Value);
}
else
{
// if we get here, it means that the category was found in the cache,
// but is not recognized by this TR instance. Therefore there's no
// need to continue search for the path on disk, because we won't find
// it there too.
return(TaxonomyReader.INVALID_ORDINAL);
}
}
// If we're still here, we have a cache miss. We need to fetch the
// value from disk, and then also put it in the cache:
int ret = TaxonomyReader.INVALID_ORDINAL;
DocsEnum docs = MultiFields.GetTermDocsEnum(indexReader, null, Consts.FULL, new BytesRef(FacetsConfig.PathToString(cp.Components, cp.Length)), 0);
if (docs != null && docs.NextDoc() != DocIdSetIterator.NO_MORE_DOCS)
{
ret = docs.DocID;
// we only store the fact that a category exists, not its inexistence.
// This is required because the caches are shared with new DTR instances
// that are allocated from doOpenIfChanged. Therefore, if we only store
// information about found categories, we cannot accidently tell a new
// generation of DTR that a category does not exist.
// LUCENENET: Lock was removed here because the underlying cache is thread-safe,
// and removing the lock seems to make the performance better.
ordinalCache.Put(cp, new Int32Class {
Value = Convert.ToInt32(ret)
});
}
return(ret);
}
public override FacetLabel GetPath(int ordinal)
{
EnsureOpen();
// Since the cache is shared with DTR instances allocated from
// doOpenIfChanged, we need to ensure that the ordinal is one that this DTR
// instance recognizes. Therefore we do this check up front, before we hit
// the cache.
if (ordinal < 0 || ordinal >= indexReader.MaxDoc)
{
return(null);
}
// TODO: can we use an int-based hash impl, such as IntToObjectMap,
// wrapped as LRU?
int catIDInteger = Convert.ToInt32(ordinal);
lock (categoryCache)
{
var res = categoryCache.Get(catIDInteger, false);
if (res != null)
{
return(res);
}
}
Document doc = indexReader.Document(ordinal);
FacetLabel ret = new FacetLabel(FacetsConfig.StringToPath(doc.Get(Consts.FULL)));
lock (categoryCache)
{
categoryCache.Put(catIDInteger, ret);
}
return(ret);
}
public virtual void TestLru()
{
LRUHashMap<string, string> lru = new LRUHashMap<string, string>(3);
Assert.AreEqual(0, lru.Size());
lru.Put("one", "Hello world");
Assert.AreEqual(1, lru.Size());
lru.Put("two", "Hi man");
Assert.AreEqual(2, lru.Size());
lru.Put("three", "Bonjour");
Assert.AreEqual(3, lru.Size());
lru.Put("four", "Shalom");
Assert.AreEqual(3, lru.Size());
Assert.NotNull(lru.Get("three"));
Assert.NotNull(lru.Get("two"));
Assert.NotNull(lru.Get("four"));
Assert.Null(lru.Get("one"));
lru.Put("five", "Yo!");
Assert.AreEqual(3, lru.Size());
Assert.Null(lru.Get("three")); // three was last used, so it got removed
Assert.NotNull(lru.Get("five"));
lru.Get("four");
lru.Put("six", "hi");
lru.Put("seven", "hey dude");
Assert.AreEqual(3, lru.Size());
Assert.Null(lru.Get("one"));
Assert.Null(lru.Get("two"));
Assert.Null(lru.Get("three"));
Assert.NotNull(lru.Get("four"));
Assert.Null(lru.Get("five"));
Assert.NotNull(lru.Get("six"));
Assert.NotNull(lru.Get("seven"));
}