/// <summary>
/// Store an exclusive child inside this node.
/// </summary>
/// <param name="key">Key for the child</param>
/// <param name="overwrite">If true, this will overwrite any existing child with a different value.</param>
/// <returns>The child node</returns>
/// <exception cref="KBExclusionException">If a non-exclusive child has already been written.</exception>
public KnowledgeBaseEntry StoreExclusive(object key, bool overwrite)
{
switch (mode)
{
case ExclusionMode.Empty:
{
mode = ExclusionMode.Exclusive;
var result = new KnowledgeBaseEntry(this, key);
if (this.Children == EmptyChildren)
{
this.Children = new List <KnowledgeBaseEntry> {
result
}
}
;
else
{
this.Children.Add(result);
}
return(result);
}
case ExclusionMode.NonExclusive:
throw new KBExclusionException("Exclusive store on non-exclusive node.");
case ExclusionMode.Exclusive:
if (overwrite)
{
this.Children[0].OverwriteExclusive(key);
}
else if (key != this.Children[0].Key)
{
throw new KBExclusionException("Exclusive store doesn't match previous store.");
}
return(this.Children[0]);
default:
throw new InvalidOperationException("Invalid exclusion mode");
}
}
/// <summary>
/// Store a non-exclusive child inside this node.
/// </summary>
/// <param name="key">Key for the new child</param>
/// <returns>The child node</returns>
/// <exception cref="KBExclusionException">If an exclusive child has already been written.</exception>
public KnowledgeBaseEntry StoreNonExclusive(object key)
{
KnowledgeBaseEntry result = null;
switch (mode)
{
case ExclusionMode.Empty:
{
mode = ExclusionMode.NonExclusive;
result = new KnowledgeBaseEntry(this, key);
if (this.Children == EmptyChildren)
{
this.Children = new List <KnowledgeBaseEntry> {
result
}
}
;
else
{
this.Children.Add(result);
}
}
break;
case ExclusionMode.Exclusive:
throw new KBExclusionException("Non-exclusive store on exclusive node.");
case ExclusionMode.NonExclusive:
foreach (var c in this.Children)
{
if (c.Key == key)
{
return(c);
}
}
this.Children.Add(result = new KnowledgeBaseEntry(this, key));
break;
}
return(result);
}
internal KnowledgeBaseEntry(KnowledgeBaseEntry parent, object key)
{
Key = key;
Parent = parent;
Children = EmptyChildren;
}
/// <summary>
/// Store a non-exclusive child inside this node.
/// </summary>
/// <param name="key">Key for the new child</param>
/// <returns>The child node</returns>
/// <exception cref="KBExclusionException">If an exclusive child has already been written.</exception>
public KnowledgeBaseEntry StoreNonExclusive(object key)
{
KnowledgeBaseEntry result =null;
switch (mode)
{
case ExclusionMode.Empty:
{
mode = ExclusionMode.NonExclusive;
result = new KnowledgeBaseEntry(this, key);
if (this.Children == EmptyChildren)
this.Children = new List<KnowledgeBaseEntry> { result };
else
this.Children.Add(result);
}
break;
case ExclusionMode.Exclusive:
throw new KBExclusionException("Non-exclusive store on exclusive node.");
case ExclusionMode.NonExclusive:
foreach (var c in this.Children)
{
if (c.Key == key)
return c;
}
this.Children.Add(result = new KnowledgeBaseEntry(this, key));
break;
}
return result;
}
/// <summary>
/// Store an exclusive child inside this node.
/// </summary>
/// <param name="key">Key for the child</param>
/// <param name="overwrite">If true, this will overwrite any existing child with a different value.</param>
/// <returns>The child node</returns>
/// <exception cref="KBExclusionException">If a non-exclusive child has already been written.</exception>
public KnowledgeBaseEntry StoreExclusive(object key, bool overwrite)
{
switch (mode)
{
case ExclusionMode.Empty:
{
mode = ExclusionMode.Exclusive;
var result = new KnowledgeBaseEntry(this, key);
if (this.Children == EmptyChildren)
this.Children = new List<KnowledgeBaseEntry> { result };
else
this.Children.Add(result);
return result;
}
case ExclusionMode.NonExclusive:
throw new KBExclusionException("Exclusive store on non-exclusive node.");
case ExclusionMode.Exclusive:
if (overwrite)
this.Children[0].OverwriteExclusive(key);
else if (key != this.Children[0].Key)
throw new KBExclusionException("Exclusive store doesn't match previous store.");
return this.Children[0];
default:
throw new InvalidOperationException("Invalid exclusion mode");
}
}
internal KnowledgeBaseEntry(KnowledgeBaseEntry parent, object key)
{
Key = key;
Parent = parent;
Children = EmptyChildren;
}
/// <summary>
/// Creates a QueryEnumerator that always returns exactly one KnowledgeBaseEntry
/// </summary>
/// <param name="e">The KnowledgeBaseEntry to return</param>
public SingletonQuery(KnowledgeBaseEntry e)
{
Current = e;
}
/// <summary>
/// Creates a QueryEnumerator that always returns exactly one KnowledgeBaseEntry
/// </summary>
/// <param name="e">The KnowledgeBaseEntry to return</param>
public SingletonQuery(KnowledgeBaseEntry e)
{
Current = e;
}