/// <summary>
/// Processes a CLEAR command
/// </summary>
/// <param name="cmd">Clear Command</param>
public void ProcessClearCommand(ClearCommand cmd)
{
this.ProcessCommand(cmd);
}
new public void ProcessClearCommand(ClearCommand cmd)
{
switch (cmd.Mode)
{
case ClearMode.Default:
case ClearMode.Graph:
_manager.DeleteGraph(cmd.TargetUri);
break;
case ClearMode.Named:
_manager.DeleteGraphs(_manager.ListGraphs().Select(u=>u.ToString()));
break;
case ClearMode.All:
_manager.DeleteGraphs(_manager.ListGraphs().Select(u=>u.ToString()).Union(new string[]{Constants.DefaultGraphUri}));
break;
}
}
/// <summary>
/// Processes a CLEAR command
/// </summary>
/// <param name="cmd">Clear Command</param>
/// <remarks>
/// Implemented by replacing the Graph with an empty Graph
/// </remarks>
public void ProcessClearCommand(ClearCommand cmd)
{
if (this._manager is IUpdateableGenericIOManager)
{
((IUpdateableGenericIOManager)this._manager).Update(cmd.ToString());
}
else
{
try
{
IGraph g;
switch (cmd.Mode)
{
case ClearMode.Default:
case ClearMode.Graph:
if (cmd.TargetUri == null && (this._manager.IOBehaviour & IOBehaviour.HasDefaultGraph) == 0) throw new SparqlUpdateException("Unable to clear the default graph as the underlying store does not support an explicit default graph");
if (cmd.TargetUri != null && (this._manager.IOBehaviour & IOBehaviour.HasNamedGraphs) == 0) throw new SparqlUpdateException("Unable to clear a named graph as the underlying store does not support named graphs");
if ((cmd.TargetUri == null && (this._manager.IOBehaviour & IOBehaviour.OverwriteDefault) != 0) || (cmd.TargetUri != null && (this._manager.IOBehaviour & IOBehaviour.OverwriteNamed) != 0))
{
//Can approximate by saving an empty Graph over the existing Graph
g = new Graph();
g.BaseUri = cmd.TargetUri;
this._manager.SaveGraph(g);
}
else if (this._manager.UpdateSupported && (this._manager.IOBehaviour & IOBehaviour.CanUpdateDeleteTriples) != 0)
{
//Can approximate by loading the Graph and then deleting all Triples from it
g = new NonIndexedGraph();
this._manager.LoadGraph(g, cmd.TargetUri);
this._manager.UpdateGraph(cmd.TargetUri, null, g.Triples);
}
else
{
throw new SparqlUpdateException("Unable to evaluate a CLEAR command as the underlying store does not provide appropriate IO Behaviour to approximate this command");
}
break;
case ClearMode.Named:
case ClearMode.All:
if ((this._manager.IOBehaviour & IOBehaviour.HasNamedGraphs) == 0) throw new SparqlUpdateException("Unable to clear named graphs as the underlying store does not support named graphs");
if (this._manager.ListGraphsSupported)
{
List<Uri> graphs = this._manager.ListGraphs().ToList();
foreach (Uri u in graphs)
{
if ((u == null && (this._manager.IOBehaviour & IOBehaviour.OverwriteDefault) != 0) || (u != null && (this._manager.IOBehaviour & IOBehaviour.OverwriteNamed) != 0))
{
//Can approximate by saving an empty Graph over the existing Graph
g = new Graph();
g.BaseUri = u;
this._manager.SaveGraph(g);
}
else if (this._manager.UpdateSupported && (this._manager.IOBehaviour & IOBehaviour.CanUpdateDeleteTriples) != 0)
{
//Can approximate by loading the Graph and then deleting all Triples from it
g = new NonIndexedGraph();
this._manager.LoadGraph(g, u);
this._manager.UpdateGraph(u, null, g.Triples);
}
else
{
throw new SparqlUpdateException("Unable to evaluate a CLEAR command as the underlying store does not provide appropriate IO Behaviour to approximate this command");
}
}
}
else
{
throw new NotSupportedException("The Generic Update processor does not support this form of the CLEAR command");
}
break;
}
}
catch
{
if (!cmd.Silent) throw;
}
}
}
/// <summary>
/// Processes a CLEAR command
/// </summary>
/// <param name="cmd">Clear Command</param>
/// <remarks>
/// Implemented by replacing the Graph with an empty Graph
/// </remarks>
public void ProcessClearCommand(ClearCommand cmd)
{
if (this._manager is IUpdateableGenericIOManager)
{
((IUpdateableGenericIOManager)this._manager).Update(cmd.ToString());
}
else
{
try
{
Graph g;
switch (cmd.Mode)
{
case ClearMode.Default:
case ClearMode.Graph:
g = new Graph();
g.BaseUri = cmd.TargetUri;
this._manager.SaveGraph(g);
break;
case ClearMode.Named:
case ClearMode.All:
if (this._manager.ListGraphsSupported)
{
List<Uri> graphs = this._manager.ListGraphs().ToList();
foreach (Uri u in graphs)
{
g = new Graph();
g.BaseUri = u;
this._manager.SaveGraph(g);
}
}
else
{
throw new NotSupportedException("The Generic Update processor does not support this form of the CLEAR command");
}
break;
}
}
catch
{
if (!cmd.Silent) throw;
}
}
}
/// <summary>
/// Processes a CLEAR command
/// </summary>
/// <param name="cmd">Clear Command</param>
/// <param name="context">SPARQL Update Evaluation Context</param>
protected virtual void ProcessClearCommandInternal(ClearCommand cmd, SparqlUpdateEvaluationContext context)
{
cmd.Evaluate(context);
}
/// <summary>
/// Processes a CLEAR command
/// </summary>
/// <param name="cmd">Clear Command</param>
public void ProcessClearCommand(ClearCommand cmd)
{
this.ProcessClearCommandInternal(cmd, this.GetContext());
}
private void TryParseClearCommand(SparqlUpdateParserContext context)
{
bool silent = false;
//May possibly have a SILENT Keyword
IToken next = context.Tokens.Dequeue();
if (next.TokenType == Token.SILENT)
{
silent = true;
next = context.Tokens.Dequeue();
}
//Then expect a GRAPH followed by a URI or one of the DEFAULT/NAMED/ALL keywords
if (next.TokenType == Token.GRAPH)
{
Uri u = this.TryParseGraphRef(context);
ClearCommand cmd = new ClearCommand(u, ClearMode.Graph, silent);
context.CommandSet.AddCommand(cmd);
}
else if (next.TokenType == Token.DEFAULT)
{
context.CommandSet.AddCommand(new ClearCommand(ClearMode.Default, silent));
}
else if (next.TokenType == Token.NAMED)
{
context.CommandSet.AddCommand(new ClearCommand(ClearMode.Named, silent));
}
else if (next.TokenType == Token.ALLWORD)
{
context.CommandSet.AddCommand(new ClearCommand(ClearMode.All, silent));
}
else
{
throw ParserHelper.Error("Unexpected Token '" + next.GetType().ToString() + "' encountered, expected a GRAPH <URI> to specify the Graph to CLEAR or one of the DEFAULT/NAMED/ALL keywords", next);
}
}
