private void MakeSpace()
{
if (_count == 0)
{
return;
}
var remove = _makeSpaceBy;
if (_count < remove)
{
remove = _count;
}
var prev = _head._prev;
for (var i = 0; i < remove; i++)
{
_removeItem((T)prev);
prev = prev._prev;
}
_count -= remove;
if (_count == 0)
{
_head = null;
}
else
{
prev._next = _head;
_head._prev = prev;
}
}
private void InitHead(LruCacheNode item)
{
_count = 1;
item._next = item;
item._prev = item;
_head = item;
}
public void Remove(LruCacheNode item)
{
if (item._next == item)
{
_head = null;
}
else
{
item._next._prev = item._prev;
item._prev._next = item._next;
if (_head == item)
{
_head = item._next;
}
}
_count--;
_removeItem((T)item);
}
public void Use(T item)
{
if (_head == item)
{
return;
}
if (_head == null)
{
InitHead(item);
return;
}
if (item._next != null)
{
item._next._prev = item._prev;
item._prev._next = item._next;
}
else
{
if (_count >= _maxCount)
{
MakeSpace();
if (_head == null)
{
InitHead(item);
return;
}
}
_count++;
}
item._next = _head;
item._prev = _head._prev;
_head._prev._next = item;
_head._prev = item;
_head = item;
}
