/// <summary>
/// Normalizes the specified URI.
/// </summary>
/// <param name="uri">The URI.</param>
/// <param name="prefix">The prefix.</param>
/// <param name="localname">The localname.</param>
/// <returns><c>true</c> if a normalization was successful; otherwise, <c>false</c>.</returns>
public override bool Normalize(string uri, out string prefix, out string localname)
{
// performance optimization: check abbreviations can contain URI by checking its length
if (uri.Length >= m_MinKeyLength && uri.Length <= m_MaxKeyLength &&
m_Abbreviations.ContainsKey(uri))
{
prefix = null;
localname = (string)m_Abbreviations[uri];
return(true);
}
else
{
return(m_OriginalNamespaceManager.Normalize(uri, out prefix, out localname));
}
}
private string URI(Entity entity)
{
if (entity is Variable && ((Variable)entity).LocalName != null)
{
return("?" + ((Variable)entity).LocalName);
}
if (entity is BNode)
{
string name = ((BNode)entity).LocalName;
if (name != null &&
(anonNameMap[name] == null || (BNode)anonNameMap[name] == entity) &&
!name.StartsWith("bnode"))
{
return("_:" + name);
}
else if (anonNames[entity] != null)
{
return((string)anonNames[entity]);
}
else
{
string id = "_:bnode" + anonNames.Count;
anonNames[entity] = id;
return(id);
}
}
string uri = entity.Uri;
string effectiveBaseUri = BaseUri == null ? "#" : BaseUri;
if (effectiveBaseUri != null && uri.StartsWith(effectiveBaseUri))
{
int len = effectiveBaseUri.Length;
bool ok = true;
for (int i = len; i < uri.Length; i++)
{
if (!char.IsLetterOrDigit(uri[i]))
{
ok = false; break;
}
}
if (ok)
{
return(":" + uri.Substring(len));
}
}
if (Format == Formats.NTriples || ns == null)
{
return("<" + Escape(uri) + ">");
}
string ret = ns.Normalize(uri);
if (ret[0] != '<')
{
return(ret);
}
return("<" + Escape(uri) + ">");
}
private void Normalize(string uri, out string prefix, out string localname)
{
if (uri == "")
{
throw new InvalidOperationException("The empty URI cannot be used as an element node.");
}
if (BaseUri == null && uri.StartsWith("#"))
{
// This isn't quite right, but it prevents dieing
// for something not uncommon in N3. The hash
// gets lost.
prefix = "";
localname = uri.Substring(1);
return;
}
if (ns.Normalize(uri, out prefix, out localname))
{
return;
}
// No namespace prefix was registered, so come up with something.
int last = uri.LastIndexOfAny(normalizechars);
if (last <= 0)
{
throw new InvalidOperationException("No namespace was registered and no prefix could be automatically generated for <" + uri + ">");
}
int prev = uri.LastIndexOfAny(normalizechars, last - 1);
if (prev <= 0)
{
throw new InvalidOperationException("No namespace was registered and no prefix could be automatically generated for <" + uri + ">");
}
string n = uri.Substring(0, last + 1);
localname = uri.Substring(last + 1);
// TODO: Make sure the local name (here and anywhere in this
// class) is a valid XML name.
if (Namespaces.GetPrefix(n) != null)
{
prefix = Namespaces.GetPrefix(n);
return;
}
prefix = uri.Substring(prev + 1, last - prev - 1);
// Remove all non-xmlable (letter) characters.
StringBuilder newprefix = new StringBuilder();
foreach (char c in prefix)
{
if (char.IsLetter(c))
{
newprefix.Append(c);
}
}
prefix = newprefix.ToString();
if (prefix.Length == 0 || prefix == "xmlns")
{
// There were no letters in the prefix or the prefix was "xmlns", which isn't valid!
prefix = "ns";
}
if (Namespaces.GetNamespace(prefix) == null)
{
doc.DocumentElement.SetAttribute("xmlns:" + prefix, n);
Namespaces.AddNamespace(n, prefix);
return;
}
int ctr = 1;
while (true)
{
if (Namespaces.GetNamespace(prefix + ctr) == null)
{
prefix += ctr;
doc.DocumentElement.SetAttribute("xmlns:" + prefix, n);
Namespaces.AddNamespace(n, prefix);
return;
}
ctr++;
}
}