public ClassEntry Search(uint cid)
{
//time consuming operations, that's the reason for cache
if (m_cid_cache.ContainsKey(cid))
{
ClassEntry t = (ClassEntry)m_cid_cache[cid];
t.BreakLinks();
t.BuildLinks(m_LRU, m_LRU.Next);
return(t);
}
else
{
//do the sequential search, :(
OOD.Imp.Storage.BTree.BTEnumerator bt = m_tree.GetEnumerator();
while (bt.MoveNext())
{
KCatalog key = (KCatalog)bt.Current;
Debug.Assert(key != null);
if (key.ClassInfo != null && key.ClassInfo.CId == cid)
{
//found
_put_in_cache(cid, key.ClassName, key.ClassInfo.FieldNames, key.ClassInfo.TopNodeSId);
return((ClassEntry)m_cid_cache[cid]);
}
}
return(null);
}
}
public bool Insert(string className, string[] fields, uint topNodeSId, ref uint assignedCId)
{
if (m_name_cache.ContainsKey(className))
{
return(false);
}
//no duplicates allowed.
if (Search(className) != null)
{
return(false);
}
assignedCId = m_next_cid++;
KCatalog key = new KCatalog(className);
DCatalog data = new DCatalog(assignedCId, fields, topNodeSId);
key.ClassInfo = data;
bool succeed = m_tree.Insert(key);
if (succeed)
{
_put_in_cache(assignedCId, className, fields, topNodeSId);
}
return(succeed);
}
public ClassEntry Search(string className)
{
if (m_name_cache.ContainsKey(className))
{
ClassEntry result = (ClassEntry)m_name_cache[className];
result.BreakLinks();
result.BuildLinks(m_LRU, m_LRU.Next);
return(result);
}
else
{
//not in cache, get it from disk
KCatalog target = new KCatalog(className);
KCatalog t = (KCatalog)m_tree.Search(target);
if (t != null)
{
_put_in_cache(t.ClassInfo.CId, className, t.ClassInfo.FieldNames, t.ClassInfo.TopNodeSId);
return((ClassEntry)m_cid_cache[t.ClassInfo.CId]);
}
else
{
return(null);
}
}
}
public IKey Deserialize(byte[] bytes, int offset, int count)
{
int pos = offset;
KCatalog result = new KCatalog();
short len = OOD.Utility.Bytes.Unpack2(bytes, pos);
pos += 2;
result.m_className = System.Text.ASCIIEncoding.ASCII.GetString(bytes, pos, len);
pos += len;
if (count > len + 2)
{
DCatalog catFactory = new DCatalog();
result.m_info = (DCatalog)catFactory.Deserialize(bytes, pos, count - len - 2);
}
return(result);
}
public bool Insert(string className, string[] fields, uint topNodeSId, ref uint assignedCId)
{
if (m_name_cache.ContainsKey(className))
return false;
//no duplicates allowed.
if (Search(className) != null)
return false;
assignedCId = m_next_cid++;
KCatalog key = new KCatalog(className);
DCatalog data = new DCatalog(assignedCId, fields, topNodeSId);
key.ClassInfo = data;
bool succeed = m_tree.Insert(key);
if (succeed)
_put_in_cache(assignedCId, className, fields, topNodeSId);
return succeed;
}
public ClassEntry Search(string className)
{
if (m_name_cache.ContainsKey(className))
{
ClassEntry result = (ClassEntry)m_name_cache[className];
result.BreakLinks();
result.BuildLinks(m_LRU, m_LRU.Next);
return result;
}
else
{
//not in cache, get it from disk
KCatalog target = new KCatalog(className);
KCatalog t = (KCatalog)m_tree.Search(target);
if (t != null)
{
_put_in_cache(t.ClassInfo.CId, className, t.ClassInfo.FieldNames, t.ClassInfo.TopNodeSId);
return (ClassEntry)m_cid_cache[t.ClassInfo.CId];
}
else
return null;
}
}
public bool UpdateTopNodeSId(string className, uint newTopNodeSId)
{
ClassEntry oldValue = Search(className);
if (oldValue != null)
{
//update cache
((ClassEntry)m_cid_cache[oldValue.CId]).SetTopNodeSId(newTopNodeSId);
//update the b-tree file
KCatalog newKey = new KCatalog(className);
newKey.ClassInfo = new DCatalog(oldValue.CId, oldValue.FieldNames, newTopNodeSId);
if (m_tree.UpdateData(newKey) == false)
{
throw new OOD.Exception.ProgramLogicError(
this,
"Update operation failed for class info b-tree.");
}
return(true);
}
else
{
return(false);
}
}
public int CompareTo(IKey B)
{
KCatalog kb = (KCatalog)B;
return(string.Compare(this.m_className, kb.m_className, false, System.Globalization.CultureInfo.InvariantCulture));
}
public IKey Deserialize(byte[] bytes, int offset, int count)
{
int pos = offset;
KCatalog result = new KCatalog();
short len = OOD.Utility.Bytes.Unpack2(bytes, pos);
pos += 2;
result.m_className = System.Text.ASCIIEncoding.ASCII.GetString(bytes, pos, len);
pos += len;
if (count > len + 2)
{
DCatalog catFactory = new DCatalog();
result.m_info = (DCatalog)catFactory.Deserialize(bytes, pos, count - len - 2);
}
return result;
}
public bool UpdateTopNodeSId(string className, uint newTopNodeSId)
{
ClassEntry oldValue = Search(className);
if (oldValue != null)
{
//update cache
((ClassEntry)m_cid_cache[oldValue.CId]).SetTopNodeSId(newTopNodeSId);
//update the b-tree file
KCatalog newKey = new KCatalog(className);
newKey.ClassInfo = new DCatalog(oldValue.CId, oldValue.FieldNames, newTopNodeSId);
if (m_tree.UpdateData(newKey) == false)
throw new OOD.Exception.ProgramLogicError(
this,
"Update operation failed for class info b-tree.");
return true;
}
else
return false;
}
