private AhoCorasickTreeNode(AhoCorasickTreeNode parent, char value)
{
Value = value;
_parent = parent;
_results = new List <string>();
_entries = new Entry[0];
}
public AhoCorasickTree(IEnumerable <string> keywords)
{
Root = new AhoCorasickTreeNode();
if (keywords != null)
{
foreach (var p in keywords)
{
AddPatternToTree(p);
}
SetFailureNodes();
// needed for offsets ;)
SetOffsets();
CreateArray();
}
}
private AhoCorasickTreeNode GetTransition(char c, ref AhoCorasickTreeNode pointer)
{
AhoCorasickTreeNode transition = null;
while (transition == null)
{
transition = pointer.GetTransition(c);
if (pointer == Root)
{
break;
}
if (transition == null)
{
pointer = pointer.Failure;
}
}
return(transition);
}
private bool Contains(string text, bool onlyStarts)
{
var pointer = Root;
for (var i = 0; i < text.Length; i++)
{
AhoCorasickTreeNode transition = null;
while (transition == null)
{
transition = pointer.GetTransition(text[i]);
if (pointer == Root)
{
break;
}
if (transition == null)
{
pointer = pointer.Failure;
}
}
if (transition != null)
{
pointer = transition;
}
else if (onlyStarts)
{
return(false);
}
if (pointer.Results.Count > 0)
{
return(true);
}
}
return(false);
}
public AhoCorasickTreeNode AddTransition(char c)
{
var node = new AhoCorasickTreeNode(this, c);
if (_size == 0)
{
Resize();
}
while (true)
{
var ind = c & (_size - 1);
if (_entries[ind].Key != 0 && _entries[ind].Key != c)
{
Resize();
continue;
}
_entries[ind].Key = c;
_entries[ind].Value = node;
return(node);
}
}
