private Resource ReadResource2(ParseContext context, bool allowDirective, out bool reverse, out bool forgetBNode) {
reverse = false;
forgetBNode = false;
Location loc = context.Location;
object tok = ReadToken(context.source, context);
if (tok is Literal)
return (Literal)tok;
string str = (string)tok;
if (str == "")
return null;
// Directives
if (str == "@prefix") {
if (allowDirective)
return PrefixResource;
else
OnError("The directive '" + str + "' is not allowed here", loc);
}
if (str == "@keywords") {
if (allowDirective)
return KeywordsResource;
else
OnError("The directive '" + str + "' is not allowed here", loc);
}
if (str == "@base") {
if (allowDirective)
return BaseResource;
else
OnError("The directive '" + str + "' is not allowed here", loc);
}
// @ Keywords
if (context.UsingKeywords && context.Keywords.Contains(str))
str = "@" + str;
if (!context.UsingKeywords &&
( str == "a" || str == "has" || str == "is"))
str = "@" + str;
// Standard Keywords
// TODO: Turn these off with @keywords
if (str == "@a")
return entRDFTYPE;
if (str == "=")
return entDAMLEQUIV;
if (str == "=>")
return entLOGIMPLIES;
if (str == "<=") {
reverse = true;
return entLOGIMPLIES;
}
if (str == "=:>") // SPECIAL EXTENSION!
return entGRAPHCONTAINS;
if (str == "@has") // ignore this token
return ReadResource2(context, false, out reverse, out forgetBNode);
if (str == "@is") {
// Reverse predicate
bool reversetemp;
Resource pred = ReadResource2(context, false, out reversetemp, out forgetBNode);
reverse = true;
string of = ReadToken(context.source, context) as string;
if (of == null) OnError("End of stream while expecting 'of'", loc);
if (of == "@of"
|| (!context.UsingKeywords && of == "of")
|| (context.UsingKeywords && context.Keywords.Contains("of") && of == "of"))
return pred;
OnError("Expecting token 'of' but found '" + of + "'", loc);
return null; // unreachable
}
if (str.StartsWith("@"))
OnError("The " + str + " directive is not supported", loc);
// URI
if (str.StartsWith("<") && str.EndsWith(">")) {
string uri = GetAbsoluteUri(BaseUri, str.Substring(1, str.Length-2));
string urierror = Entity.ValidateUri(uri);
if (urierror != null)
OnWarning(urierror, loc);
return GetResource(context, uri);
}
// VARIABLE
if (str[0] == '?') {
string name = str.Substring(1);
Entity varb = (Entity)context.variables[name];
if (varb == null) {
varb = new Variable(name);
AddVariable((Variable)varb);
context.variables[name] = varb;
}
return varb;
}
// QNAME
if (str.IndexOf(":") != -1)
return ResolveQName(str, context, loc);
// ANONYMOUS
if (str == "[") {
Entity ret = new BNode();
ReadWhitespace(context.source);
if (context.source.Peek() != ']') {
char bracket = ReadPredicates(ret, context);
if (bracket == '.')
bracket = ReadPunc(context.source);
if (bracket != ']')
OnError("Expected a close bracket but found '" + bracket + "'", loc);
} else {
context.source.Read();
}
forgetBNode = true;
return ret;
}
// LIST
if (str == "(") {
// A list
Entity head = null, ent = null;
while (true) {
bool rev2, fb2;
Resource res = ReadResource(context, false, out rev2, out fb2);
if (res == null)
break;
if (ent == null) {
ent = new BNode();
head = ent;
} else {
Entity sub = new BNode();
Add(context.store, new Statement(ent, entRDFREST, sub, context.meta), loc);
ent = sub;
}
Add(context.store, new Statement(ent, entRDFFIRST, res, context.meta), loc);
if (fb2) DoForget(res, context);
}
if (head == null) // No list items.
head = entRDFNIL; // according to Turtle spec
else
Add(context.store, new Statement(ent, entRDFREST, entRDFNIL, context.meta), loc);
return head;
}
if (str == ")")
return null; // Should I use a more precise end-of-list return value?
// FORMULA
if (str == "{") {
// ParseContext is a struct, so this gives us a clone.
ParseContext newcontext = context;
// The formula is denoted by a blank node, unless we set
// the override meta flag above.
if (context.overrideMeta == null)
newcontext.meta = new BNode();
else
newcontext.meta = context.overrideMeta;
// According to the spec, _:xxx anonymous nodes are
// local to the formula. But ?$variables (which aren't
// mentioned in the spec) are treated as global names.
newcontext.anonymous = new Hashtable();
while (NextPunc(context.source) != '}' && ReadStatement(newcontext)) { }
ReadWhitespace(context.source);
if (context.source.Peek() == '}') context.source.Read();
return newcontext.meta;
}
// NUMERIC LITERAL
// In Turtle, numbers are restricted to [0-9]+, and are datatyped xsd:integer.
double numval;
#if !SILVERLIGHT
if (double.TryParse(str, System.Globalization.NumberStyles.Any, null, out numval)) {
#else
bool ok = true;
numval = 0;
try {
numval = double.Parse(str);
} catch (Exception) {
ok = false;
}
if (ok) {
#endif
if (numval >= long.MinValue && numval <= long.MaxValue && numval == (double)(long)numval)
return new Literal(((long)numval).ToString(), null, NS.XMLSCHEMA + "integer");
else
return new Literal(numval.ToString(), null, NS.XMLSCHEMA + "double");
}
//BOOLEAN LITERAL
if (str == "true" || str == "false") {
return new Literal(str,null,NS.XMLSCHEMA+"boolean");
}
// If @keywords is used, alphanumerics that aren't keywords
// are local names in the default namespace.
if (context.UsingKeywords && char.IsLetter(str[0])) {
if (BaseUri == null)
OnError("The document contains an unqualified name but no BaseUri was specified: \"" + str + "\"", loc);
return GetResource(context, BaseUri + str);
}
// NOTHING MATCHED
OnError("Invalid token: " + str, loc);
return null;
}
private void Add(StatementSink store, Statement statement, Location position) {
store.Add(statement);
}
public override void Run(SelectableSource source, QueryResultSink resultsink) {
if (!(query is SelectQuery))
throw new InvalidOperationException("Only SELECT queries are supported by this method (" + query.GetType() + ").");
// Perform the query
SelectQuery squery = (SelectQuery)query;
RdfSourceWrapper sourcewrapper = new RdfSourceWrapper(source, QueryMeta, this);
MyLogicFactory logic = new MyLogicFactory();
foreach (RdfFunction f in extFunctions)
logic.registerExternalFunction(
new URIWrapper(f.Uri),
new ExtFuncWrapper(sourcewrapper, f));
squery.bindLogic(logic);
RdfBindingSet results;
try {
results = squery.execute(sourcewrapper);
} catch (java.lang.Exception e) {
throw new QueryExecutionException("Error executing query: " + e.Message, e);
}
// Prepare binding objects
java.util.List vars = results.getVariables();
VariableBinding[] bindings = new VariableBinding[vars.size()];
SparqlVariable[] svars = new SparqlVariable[vars.size()];
SemWebVariable[] vars2 = new SemWebVariable[vars.size()];
for (int i = 0; i < bindings.Length; i++) {
svars[i] = (SparqlVariable)vars.get(i);
vars2[i] = new SemWebVariable(svars[i].getName());
bindings[i] = new VariableBinding(vars2[i], null);
}
// Initialize the result sink
resultsink.Init(bindings, false, false); // set distinct and ordered
// Set the comments
resultsink.AddComments(queryString + "\n");
resultsink.AddComments(sourcewrapper.GetLog());
// Iterate the bindings
java.util.Iterator iter = results.iterator();
long ctr = -1, ctr2 = 0;
while (iter.hasNext()) {
RdfBindingRow row = (RdfBindingRow)iter.next();
// Since SPARQL processing may be lazy-delayed,
// add any new comments that might have been logged.
resultsink.AddComments(sourcewrapper.GetLog());
ctr++;
if (ctr < ReturnStart && ReturnStart != -1) continue;
for (int i = 0; i < bindings.Length; i++) {
Resource r = sourcewrapper.ToResource(row.getValue(svars[i]));
r = sourcewrapper.Persist(r);
bindings[i] = new VariableBinding(bindings[i].Variable, r);
}
resultsink.AddComments(sourcewrapper.GetLog());
resultsink.Add(bindings);
ctr2++;
if (ctr2 >= ReturnLimit && ReturnLimit != -1) break;
}
resultsink.AddComments(sourcewrapper.GetLog());
// Close the result sink.
resultsink.Finished();
}
public void InteropSemWebNativeStore()
{
//Get the Talis Connection
TalisPlatformConnector talis = new TalisPlatformConnector("rvesse-dev1", "rvesse", "4kn478wj");
Assert.IsNotNull(talis);
//Create a Talis Triple Store
TalisTripleStore store = new TalisTripleStore(talis);
//Create the Native Store Source
NativeStoreSource source = new NativeStoreSource(store);
Console.WriteLine("All Statements in the Store");
source.Select(new SemWebConsolePrinter());
Console.WriteLine();
Console.Write("Does a FordFiesta exist in the Store? ");
Console.WriteLine(source.Contains(new Entity("http://example.org/vehicles/FordFiesta")));
Console.WriteLine();
Console.Write("Does a Monkey exist in the Store? ");
Console.WriteLine(source.Contains(new Entity("http://example.org/Monkey")));
Console.WriteLine();
Console.Write("Do any Cars exist in the Store? ");
Statement cars = new Statement(null, new Entity(RdfSpecsHelper.RdfType), new Entity("http://example.org/vehicles/Car"));
Console.WriteLine(source.Contains(cars));
Console.WriteLine();
Console.Write("Do any Gorillas exist in the Store?");
Statement gorillas = new Statement(null, new Entity(RdfSpecsHelper.RdfType), new Entity("http://example.org/Gorilla"));
Console.WriteLine(source.Contains(gorillas));
Console.WriteLine();
Console.WriteLine("What Cars exists in the Store?");
source.Select(new Statement(null, new Entity(RdfSpecsHelper.RdfType), new Entity("http://example.org/vehicles/Car")), new SemWebConsolePrinter());
Console.WriteLine();
Console.WriteLine("Cars are their Speeds from the Store?");
Variable car = new Variable("car");
Statement[] pattern = new Statement[]
{
new Statement(car, new Entity(RdfSpecsHelper.RdfType), new Entity("http://example.org/vehicles/Car")),
new Statement(car, new Entity("http://example.org/vehicles/Speed"), new Variable("speed"))
};
source.Query(pattern, new QueryOptions(), new SemWebResultsConsolePrinter());
Console.WriteLine();
}
private Resource ReadResource2(ParseContext context, out bool reverse) {
reverse = false;
Location loc = context.Location;
object tok = ReadToken(context.source, context);
if (tok is Literal)
return (Literal)tok;
string str = (string)tok;
if (str == "")
return null;
// @ Keywords
if (str == "@prefix")
return PrefixResource;
if (str == "@keywords")
return KeywordsResource;
if (context.UsingKeywords && context.Keywords.Contains(str))
str = "@" + str;
if (!context.UsingKeywords &&
( str == "a" || str == "has" || str == "is"))
str = "@" + str;
// Standard Keywords
// TODO: Turn these off with @keywords
if (str == "@a")
return entRDFTYPE;
if (str == "=")
return entDAMLEQUIV;
if (str == "=>")
return entLOGIMPLIES;
if (str == "<=") {
reverse = true;
return entLOGIMPLIES;
}
if (str == "@has") // ignore this token
return ReadResource2(context, out reverse);
if (str == "@is") {
// Reverse predicate
bool reversetemp;
Resource pred = ReadResource2(context, out reversetemp);
reverse = true;
string of = ReadToken(context.source, context) as string;
if (of == null) OnError("End of stream while expecting 'of'", loc);
if (of == "@of"
|| (!context.UsingKeywords && of == "of")
|| (context.UsingKeywords && context.Keywords.Contains("of") && of == "of"))
return pred;
OnError("Expecting token 'of' but found '" + of + "'", loc);
return null; // unreachable
}
if (str.StartsWith("@"))
OnError("The " + str + " directive is not supported", loc);
// URI
if (str.StartsWith("<") && str.EndsWith(">")) {
string uri = GetAbsoluteUri(BaseUri, str.Substring(1, str.Length-2));
return GetResource(context, uri);
}
// VARIABLE
if (str[0] == '?') {
string name = str.Substring(1);
Entity var = (Entity)context.variables[name];
if (var == null) {
var = new Variable(name);
AddVariable((Variable)var);
context.variables[name] = var;
}
return var;
}
// QNAME
if (str.IndexOf(":") != -1)
return ResolveQName(str, context, loc);
// ANONYMOUS
if (str == "[") {
Entity ret = new BNode();
ReadWhitespace(context.source);
if (context.source.Peek() != ']') {
char bracket = ReadPredicates(ret, context);
if (bracket == '.')
bracket = ReadPunc(context.source);
if (bracket != ']')
OnError("Expected a close bracket but found '" + bracket + "'", loc);
} else {
context.source.Read();
}
return ret;
}
// LIST
if (str == "(") {
// A list
Entity ent = null;
while (true) {
bool rev2;
Resource res = ReadResource(context, out rev2);
if (res == null)
break;
if (ent == null) {
ent = new BNode();
} else {
Entity sub = new BNode();
Add(context.store, new Statement(ent, entRDFREST, sub, context.meta), loc);
ent = sub;
}
Add(context.store, new Statement(ent, entRDFFIRST, res, context.meta), loc);
}
if (ent == null) // No list items.
ent = entRDFNIL; // according to Turtle spec
else
Add(context.store, new Statement(ent, entRDFREST, entRDFNIL, context.meta), loc);
return ent;
}
if (str == ")")
return null; // Should I use a more precise end-of-list return value?
// FORMULA
if (str == "{") {
// ParseContext is a struct, so this gives us a clone.
ParseContext newcontext = context;
// The formula is denoted by a blank node
newcontext.meta = new BNode();
// According to the spec, _:xxx anonymous nodes are
// local to the formula. But ?$variables (which aren't
// mentioned in the spec) are treated as global names.
newcontext.anonymous = new Hashtable();
while (NextPunc(context.source) != '}' && ReadStatement(newcontext)) { }
ReadWhitespace(context.source);
if (context.source.Peek() == '}') context.source.Read();
return newcontext.meta;
}
// NUMERIC LITERAL
// In Turtle, numbers are restricted to [0-9]+, and are datatyped xsd:integer.
double numval;
if (double.TryParse(str, System.Globalization.NumberStyles.Any, null, out numval))
return new Literal(numval.ToString());
// If @keywords is used, alphanumerics that aren't keywords
// are local names in the default namespace.
if (context.UsingKeywords && char.IsLetter(str[0])) {
if (BaseUri == null)
OnError("The document contains an unqualified name but no BaseUri was specified: \"" + str + "\"", loc);
return GetResource(context, BaseUri + str);
}
// NOTHING MATCHED
OnError("Invalid token: " + str, loc);
return null;
}
public override void Init(Variable[] variables) {
for (int i = 0; i < variables.Length; i++) {
if (variables[i].LocalName == "subject") si = i;
if (variables[i].LocalName == "predicate") pi = i;
if (variables[i].LocalName == "object") oi = i;
}
}
public void InteropSemWebGraphQuery()
{
Graph g = new Graph();
FileLoader.Load(g, "InferenceTest.ttl");
GraphSource source = new GraphSource(g);
Console.WriteLine("Query for Cars and their Speeds");
Console.WriteLine();
SemWeb.Query.SparqlXmlQuerySink sink = new SemWeb.Query.SparqlXmlQuerySink(Console.Out);
Variable car = new Variable("car");
Statement[] graphPattern = new Statement[]
{
new Statement(car, new Entity(RdfSpecsHelper.RdfType), new Entity("http://example.org/vehicles/Car")),
new Statement(car, new Entity("http://example.org/vehicles/Speed"), new Variable("speed"))
};
source.Query(graphPattern, new SemWeb.Query.QueryOptions(), sink);
Console.WriteLine("Query for the 1st Car and it's Speed");
Console.WriteLine();
sink = new SemWeb.Query.SparqlXmlQuerySink(Console.Out);
graphPattern = new Statement[]
{
new Statement(car, new Entity(RdfSpecsHelper.RdfType), new Entity("http://example.org/vehicles/Car")),
new Statement(car, new Entity("http://example.org/vehicles/Speed"), new Variable("speed"))
};
SemWeb.Query.QueryOptions options = new SemWeb.Query.QueryOptions();
options.Limit = 1;
source.Query(graphPattern, options, sink);
}
private static ArrayList prove(Hashtable cases, SelectableSource world, Statement[] goal, int maxNumberOfSteps)
{
// This is the main routine from euler.js.
// cases: Resource (predicate) => IList of Sequent
if (world != null) // cache our queries to the world, if a world is provided
world = new SemWeb.Stores.CachedSource(world);
StatementMap cached_subproofs = new StatementMap();
// Create the queue and add the first item.
ArrayList queue = new ArrayList();
{
QueueItem start = new QueueItem();
start.env = new Hashtable();
start.rule = new Sequent(Statement.All, goal, null);
start.src = null;
start.ind = 0;
start.parent = null;
start.ground = new ArrayList();
queue.Add(start);
if (Debug) Console.Error.WriteLine("Euler: Queue: " + start);
}
// The evidence array holds the results of this proof.
ArrayList evidence = new ArrayList();
// Track how many steps we take to not go over the limit.
int step = 0;
// Process the queue until it's empty or we reach our step limit.
while (queue.Count > 0) {
// deal with the QueueItem at the top of the queue
QueueItem c = (QueueItem)queue[queue.Count-1];
queue.RemoveAt(queue.Count-1);
ArrayList g = new ArrayList(c.ground);
// have we done too much?
step++;
if (maxNumberOfSteps != -1 && step >= maxNumberOfSteps) {
if (Debug) Console.Error.WriteLine("Euler: Maximum number of steps exceeded. Giving up.");
return null;
}
// if each statement in the body of the sequent has been proved
if (c.ind == c.rule.body.Length) {
// if this is the top-level sequent being proved; we've found a complete evidence for the goal
if (c.parent == null) {
EvidenceItem ev = new EvidenceItem();
ev.head = new Statement[c.rule.body.Length];
bool canRepresentHead = true;
for (int i = 0; i < c.rule.body.Length; i++) {
ev.head[i] = evaluate(c.rule.body[i], c.env);
if (ev.head[i].AnyNull) // can't represent it: literal in subject position, for instance
canRepresentHead = false;
}
ev.body = c.ground;
ev.env = c.env;
if (Debug) Console.Error.WriteLine("Euler: Found Evidence: " + ev);
if (!canRepresentHead)
continue;
evidence.Add(ev);
// this is a subproof of something; whatever it is a subgroup for can
// be incremented
} else {
// if the rule had no body, it was just an axiom and we represent that with Ground
if (c.rule.body.Length != 0) g.Add(new Ground(c.rule, c.env));
// advance the parent being proved and put the advanced
// parent into the queue; unify the parent variable assignments
// with this one's
QueueItem r = new QueueItem();
r.rule = c.parent.rule;
r.src = c.parent.src;
r.ind = c.parent.ind;
r.parent = c.parent.parent;
r.env = (Hashtable)c.parent.env.Clone();
r.ground = g;
unify(c.rule.head, c.env, r.rule.body[r.ind], r.env, true);
r.ind++;
queue.Add(r);
if (Debug) Console.Error.WriteLine("Euler: Queue Advancement: " + r);
// The number of live children for this parent is decremented since we are
// done with this subproof, but we store the result for later.
if (c.parent.solutions == null)
c.parent.solutions = new StatementList();
c.parent.solutions.Add(evaluate(r.rule.body[r.ind-1], r.env));
decrementLife(c.parent, cached_subproofs);
}
// this sequent still has parts of the body left to be proved; try to
// find evidence for the next statement in the body, and if we find
// evidence, queue up that evidence
} else {
// this is the next part of the body that we need to try to prove
Statement t = c.rule.body[c.ind];
// Try to process this predicate with a user-provided custom
// function that resolves things like mathematical relations.
// euler.js provides similar functionality, but the system
// of user predicates is completely different here.
RdfRelation b = FindUserPredicate(t.Predicate);
if (b != null) {
Resource[] args;
Variable[] unifyResult;
Resource value = evaluate(t.Object, c.env);
if (!c.rule.callArgs.ContainsKey(t.Subject)) {
// The array of arguments to this relation is just the subject of the triple itself
args = new Resource[] { evaluate(t.Subject, c.env) };
unifyResult = new Variable[1];
if (t.Subject is Variable) unifyResult[0] = (Variable)t.Subject;
} else {
// The array of arguments to this relation comes from a pre-grouped arg list.
args = (Resource[])((ICloneable)c.rule.callArgs[t.Subject]).Clone();
unifyResult = new Variable[args.Length];
for (int i = 0; i < args.Length; i++) {
if (args[i] is Variable) {
unifyResult[i] = (Variable)args[i];
args[i] = evaluate(args[i], c.env);
}
}
}
// Run the user relation on the array of arguments (subject) and on the object.
if (b.Evaluate(args, ref value)) {
// If it succeeds, we press on.
// The user predicate may update the 'value' variable and the argument
// list array, and so we want to unify any variables in the subject
// or object of this user predicate with the values given to us
// by the user predicate.
Hashtable newenv = (Hashtable)c.env.Clone();
if (t.Object is Variable) unify(value, null, t.Object, newenv, true);
for (int i = 0; i < args.Length; i++)
if (unifyResult[i] != null)
unify(args[i], null, unifyResult[i], newenv, true);
Statement grnd = evaluate(t, newenv);
if (grnd != Statement.All) // sometimes not representable, like if literal as subject
g.Add(new Ground(new Sequent(grnd, new Statement[0], null), new Hashtable()));
QueueItem r = new QueueItem();
r.rule = c.rule;
r.src = c.src;
r.ind = c.ind;
r.parent = c.parent;
r.env = newenv;
r.ground = g;
r.ind++;
queue.Add(r);
// Note: Since we are putting something back in for c, we don't touch the life counter on the parent.
} else {
// If the predicate fails, decrement the life of the parent.
if (c.parent != null)
decrementLife(c.parent, cached_subproofs);
}
continue;
}
// t can be proved either by the use of a rule
// or if t literally exists in the world
Statement t_resolved = evaluate(t, c.env);
// If resolving this statement requires putting a literal in subject or predicate position, we
// can't prove it.
if (t_resolved == Statement.All) {
if (c.parent != null)
decrementLife(c.parent, cached_subproofs);
continue;
}
ArrayList tcases = new ArrayList();
// See if we have already tried to prove this.
if (cached_subproofs.ContainsKey(t_resolved)) {
StatementList cached_solutions = (StatementList)cached_subproofs[t_resolved];
if (cached_solutions == null) {
if (Debug) Console.Error.WriteLine("Euler: Dropping queue item because we have already failed to prove it: " + t_resolved);
} else {
foreach (Statement s in cached_solutions) {
if (Debug) Console.Error.WriteLine("Euler: Using Cached Axiom: " + s);
Sequent seq = new Sequent(s);
tcases.Add(seq);
}
}
} else {
// get all of the rules that apply to the predicate in question
if (t_resolved.Predicate != null && cases.ContainsKey(t_resolved.Predicate))
tcases.AddRange((IList)cases[t_resolved.Predicate]);
if (cases.ContainsKey("WILDCARD"))
tcases.AddRange((IList)cases["WILDCARD"]);
// if t has no unbound variables and we've matched something from
// the axioms, don't bother looking at the world, and don't bother
// proving it any other way than by the axiom.
bool lookAtWorld = true;
foreach (Sequent seq in tcases) {
if (seq.body.Length == 0 && seq.head == t_resolved) {
lookAtWorld = false;
tcases.Clear();
tcases.Add(seq);
break;
}
}
// if there is a seprate world, get all of the world
// statements that witness t
if (world != null && lookAtWorld) {
MemoryStore w = new MemoryStore();
if (Debug) Console.Error.WriteLine("Running " + c);
if (Debug) Console.Error.WriteLine("Euler: Ask World: " + t_resolved);
world.Select(t_resolved, w);
foreach (Statement s in w) {
if (Debug) Console.Error.WriteLine("Euler: World Select Response: " + s);
Sequent seq = new Sequent(s);
tcases.Add(seq);
}
}
}
// If there is no evidence or potential evidence (i.e. rules)
// for t, then we will dump this QueueItem by not queuing any
// subproofs.
// Otherwise we try each piece of evidence in turn.
foreach (Sequent rl in tcases) {
ArrayList g2 = (ArrayList)c.ground.Clone();
if (rl.body.Length == 0) g2.Add(new Ground(rl, new Hashtable()));
QueueItem r = new QueueItem();
r.rule = rl;
r.src = rl;
r.ind = 0;
r.parent = c;
r.env = new Hashtable();
r.ground = g2;
if (unify(t, c.env, rl.head, r.env, true)) {
QueueItem ep = c; // euler path
while ((ep = ep.parent) != null)
if (ep.src == c.src && unify(ep.rule.head, ep.env, c.rule.head, c.env, false))
break;
if (ep == null) {
// It is better for caching subproofs to work an entire proof out before
// going on, which means we want to put the new queue item at the
// top of the stack.
queue.Add(r);
c.liveChildren++;
if (Debug) Console.Error.WriteLine("Euler: Queue from Axiom: " + r);
}
}
}
// If we did not add anything back into the queue for this item, then
// we decrement the life of the parent.
if (c.liveChildren == 0 && c.parent != null)
decrementLife(c.parent, cached_subproofs);
}
}
return evidence;
}
/// <summary>
/// Writes the specified variable to the output writer.
/// </summary>
/// <param name="variable">The variable.</param>
protected virtual void WriteVariable(Variable variable)
{
Write("?");
WriteEscaped(variable.LocalName ?? ("var" + Math.Abs(variable.GetHashCode())));
}
public override void Init(Variable[] variables)
{
output.WriteLine("<table>");
output.WriteLine("<tr>");
foreach (Variable var in variables) {
if (var.LocalName == null) continue;
output.WriteLine("<th>" + var.LocalName + "</th>");
}
output.WriteLine("</tr>");
}
public override void Query(Statement[] graph, SemWeb.Query.QueryOptions options, SelectableSource targetModel, SemWeb.Query.QueryResultSink sink)
{
QueryCheckArg(graph);
// Try to do the inferencing.
ArrayList evidence = prove(rules, targetModel, graph, -1);
if (evidence == null)
return; // not provable (in max number of steps, if that were given)
// Then send the possible bindings to the QueryResultSink.
// Map variables to indexes.
Hashtable vars = new Hashtable();
foreach (Statement s in graph) {
if (s.Subject is Variable && !vars.ContainsKey(s.Subject)) vars[s.Subject] = vars.Count;
if (s.Predicate is Variable && !vars.ContainsKey(s.Predicate)) vars[s.Predicate] = vars.Count;
if (s.Object is Variable && !vars.ContainsKey(s.Object)) vars[s.Object] = vars.Count;
}
// Prepare the bindings array.
Variable[] varOrder = new Variable[vars.Count];
foreach (Variable v in vars.Keys)
varOrder[(int)vars[v]] = v;
// Initialize the sink.
sink.Init(varOrder);
// Send a binding set for each piece of evidence.
foreach (EvidenceItem ei in evidence) {
// Write a comment to the results with the actual proof. (nifty actually)
sink.AddComments(ei.ToProof().ToString());
// Create the binding array and send it on
Resource[] variableBindings = new Resource[varOrder.Length];
foreach (Variable v in vars.Keys)
if (ei.env.ContainsKey(v))
variableBindings[(int)vars[v]] = (Resource)ei.env[v];
sink.Add(new SemWeb.Query.VariableBindings(varOrder, variableBindings));
}
// Close the sink.
sink.Finished();
}
public override void Init(Variable[] variables)
{
bool first = true;
foreach (Variable var in variables) {
if (var.LocalName == null) continue;
if (!first) output.Write(","); first = false;
output.Write(var.LocalName);
}
output.WriteLine();
}
public override void Init(Variable[] variables) {
output.WriteStartElement("sparql","http://www.w3.org/2007/SPARQL/results#");//http://www.w3.org/2007/SPARQL/results#
output.WriteStartElement("head");
foreach (Variable var in variables) {
if (var.LocalName == null) continue;
output.WriteStartElement("variable");
output.WriteAttributeString("name", var.LocalName);
output.WriteEndElement();
}
output.WriteEndElement(); // head
output.WriteStartElement("results");
// instead of <results>, we might want <boolean>true</boolean>
}
public override void Init(Variable[] variables) {
vars = new Variable[variables.Length];
for (int i = 0; i < variables.Length; i++)
vars[i] = (Variable)variableNames[variables[i].LocalName];
sink.Init(vars);
}
public override void Init(Variable[] variables)
{
java.util.ArrayList vars = new java.util.ArrayList();
foreach (Variable b in variables)
if (varMap[b] != null) // because of bad treatment of meta
vars.add((SparqlVariable)varMap[b]);
bindings = new RdfBindingSetImpl(vars);
}
public override void Run(SelectableSource source, QueryResultSink resultsink)
{
if (!(query is SelectQuery))
{
throw new InvalidOperationException("Only SELECT queries are supported by this method (" + query.GetType() + ").");
}
// Perform the query
SelectQuery squery = (SelectQuery)query;
RdfSourceWrapper sourcewrapper = new RdfSourceWrapper(source, QueryMeta, this);
MyLogicFactory logic = new MyLogicFactory();
foreach (RdfFunction f in extFunctions)
{
logic.registerExternalFunction(
new URIWrapper(f.Uri),
new ExtFuncWrapper(sourcewrapper, f));
}
squery.bindLogic(logic);
RdfBindingSet results;
try {
results = squery.execute(sourcewrapper);
} catch (java.lang.Exception e) {
throw new QueryExecutionException("Error executing query: " + e.Message, e);
}
// Prepare binding objects
java.util.List vars = results.getVariables();
VariableBinding[] bindings = new VariableBinding[vars.size()];
SparqlVariable[] svars = new SparqlVariable[vars.size()];
SemWebVariable[] vars2 = new SemWebVariable[vars.size()];
for (int i = 0; i < bindings.Length; i++)
{
svars[i] = (SparqlVariable)vars.get(i);
vars2[i] = new SemWebVariable(svars[i].getName());
bindings[i] = new VariableBinding(vars2[i], null);
}
// Initialize the result sink
resultsink.Init(bindings, false, false); // set distinct and ordered
// Set the comments
resultsink.AddComments(queryString + "\n");
resultsink.AddComments(sourcewrapper.GetLog());
// Iterate the bindings
java.util.Iterator iter = results.iterator();
long ctr = -1, ctr2 = 0;
while (iter.hasNext())
{
RdfBindingRow row = (RdfBindingRow)iter.next();
// Since SPARQL processing may be lazy-delayed,
// add any new comments that might have been logged.
resultsink.AddComments(sourcewrapper.GetLog());
ctr++;
if (ctr < ReturnStart && ReturnStart != -1)
{
continue;
}
for (int i = 0; i < bindings.Length; i++)
{
Resource r = sourcewrapper.ToResource(row.getValue(svars[i]));
r = sourcewrapper.Persist(r);
bindings[i] = new VariableBinding(bindings[i].Variable, r);
}
resultsink.AddComments(sourcewrapper.GetLog());
resultsink.Add(bindings);
ctr2++;
if (ctr2 >= ReturnLimit && ReturnLimit != -1)
{
break;
}
}
resultsink.AddComments(sourcewrapper.GetLog());
// Close the result sink.
resultsink.Finished();
}
Resource ToRes(object expr, java.util.Map knownValues, bool entities, Hashtable varMap1, Hashtable varMap2, RdfSourceWrapper src, QueryOptions opts, VariableList distinguishedVars, VariableList undistinguishedVars, java.util.Set sparqlDistinguished)
{
if (expr is SparqlVariable) {
Variable v;
if (varMap1.ContainsKey(expr)) {
v = (Variable)varMap1[expr];
} else {
v = new Variable(expr.ToString());
varMap1[expr] = v;
varMap2[v] = expr;
if (knownValues != null && knownValues.get(expr) != null) {
java.util.Set values = (java.util.Set)knownValues.get(expr);
VarKnownValuesList values2 = new VarKnownValuesList();
for (java.util.Iterator iter = values.iterator(); iter.hasNext(); ) {
Resource r = src.ToResource((name.levering.ryan.sparql.common.Value)iter.next());
if (r != null)
values2.Add(r);
}
opts.VariableKnownValues[v] = values2;
}
if (sparqlDistinguished != null && sparqlDistinguished.contains(expr))
distinguishedVars.Add(v);
else
undistinguishedVars.Add(v);
}
return v;
}
return entities ? src.ToEntity((name.levering.ryan.sparql.common.Value)expr) : src.ToResource((name.levering.ryan.sparql.common.Value)expr);
}
public void InteropSemWebInMemoryStoreSource()
{
MicrosoftSqlStoreManager mssql = new MicrosoftSqlStoreManager("dotnetrdf_experimental", "sa", "20sQl08");
InMemoryStoreSource source = new InMemoryStoreSource(new SqlTripleStore(mssql));
N3Writer writer = new N3Writer(Console.Out);
Console.WriteLine("Outputting all Triples of the form ?s rdf:type ?type");
Statement template = new Statement(new Variable(), new Entity(RdfSpecsHelper.RdfType), new Variable());
source.Select(template, writer);
Console.WriteLine();
Console.WriteLine();
Console.WriteLine("Outputting all Triples of the form ?s rdf:type ?car");
template = new Statement(new Variable(), new Entity(RdfSpecsHelper.RdfType), new Entity("http://example.org/vehicles/Car"));
source.Select(template, writer);
Console.WriteLine();
Console.WriteLine();
Console.WriteLine("Outputting all Triples for Cars and Planes");
SelectFilter filter = new SelectFilter();
filter.Predicates = new Entity[] { new Entity(RdfSpecsHelper.RdfType) };
filter.Objects = new Entity[] { new Entity("http://example.org/vehicles/Car"), new Entity("http://example.org/vehicles/Plane") };
source.Select(filter, writer);
Console.WriteLine();
Console.WriteLine();
Console.WriteLine("Outputting the Speeds of all Cards");
Variable car = new Variable("car");
Statement[] pattern = new Statement[]
{
new Statement(car, new Entity(RdfSpecsHelper.RdfType), new Entity("http://example.org/vehicles/Car")),
new Statement(car, new Entity("http://example.org/vehicles/Speed"), new Variable("speed"))
};
source.Query(pattern, new QueryOptions(), new SemWebResultsConsolePrinter());
Console.WriteLine();
writer.Close();
}
protected void AddVariable(Variable variable) {
variables[variable] = variable;
}
public VariableBinding(Variable variable, Resource target) {
v = variable;
t = target;
}