private void populateBindingSets(
List<QueryBindingSet> results, Var predVar, Var objVar, Collection<Statement> stmts) {
if (predVar == null || objVar == null || stmts == null || stmts.size() == 0) return;
List<QueryBindingSet> copyOf = new ArrayList<QueryBindingSet>(results);
int i = copyOf.size();
int j = 0;
for (Iterator<Statement> iter = stmts.iterator(); iter.hasNext(); ) {
Statement st = iter.next();
int k = 0;
for (QueryBindingSet result : results) {
if (!result.hasBinding(predVar.getName()) || k >= i) {
String name = predVar.getName();
org.openrdf.model.Value val = st.getPredicate();
addBinding(result, name, val);
}
if (!result.hasBinding(objVar.getName()) || k >= i)
addBinding(result, objVar.getName(), st.getObject());
k++;
}
i = copyOf.size() + j * copyOf.size();
j++;
if (iter.hasNext()) {
// copy results
for (QueryBindingSet copy : copyOf) {
results.add(new QueryBindingSet(copy));
}
}
}
}
/**
* Converts the String representation of a {@link Var} back into the object version.
*
* @param varString - The {@link Var} represented as a String. (not null)
* @return A {@link Var} built from the string.
*/
public static Var toVar(final String varString) {
checkNotNull(varString);
if (varString.startsWith("-const-")) {
// The variable is a constant value.
final String[] varParts = varString.split(TYPE_DELIM);
final String name = varParts[0];
final String valueString = name.substring("-const-".length());
final String dataTypeString = varParts[1];
if (dataTypeString.equals(URI_TYPE)) {
// Handle a URI object.
final Var var = new Var(name, new URIImpl(valueString));
var.setAnonymous(true);
return var;
} else {
// Literal value.
final URI dataType = new URIImpl(dataTypeString);
final Literal value = new LiteralImpl(valueString, dataType);
final Var var = new Var(name, value);
var.setAnonymous(true);
return var;
}
} else {
// The variable is a named variable.
return new Var(varString);
}
}
private static String getVarName(ValueExpr v) {
if (v instanceof Var) {
Var var = (Var) v;
if (!var.isConstant()) {
return var.getName();
}
}
return null;
}
public static ColumnVar createSubj(String alias, Var v, Resource resource) {
ColumnVar var = new ColumnVar();
var.alias = alias;
var.column = "subj";
var.name = v.getName();
var.anonymous = v.isAnonymous();
var.value = resource;
var.types = ValueTypes.RESOURCE;
if (resource instanceof RdbmsURI) {
var.types = ValueTypes.URI;
}
return var;
}
public static ColumnVar createObj(String alias, Var v, Value value) {
ColumnVar var = new ColumnVar();
var.alias = alias;
var.column = "obj";
var.name = v.getName();
var.anonymous = v.isAnonymous();
var.value = value;
var.types = ValueTypes.UNKNOWN;
if (value instanceof RdbmsURI) {
var.types = ValueTypes.URI;
} else if (value instanceof RdbmsResource) {
var.types = ValueTypes.RESOURCE;
}
return var;
}
public static ColumnVar createCtx(String alias, Var v, Resource resource) {
ColumnVar var = new ColumnVar();
var.alias = alias;
var.column = "ctx";
if (v == null) {
var.name = "__ctx" + Integer.toHexString(System.identityHashCode(var));
var.anonymous = true;
var.hidden = true;
} else {
var.name = v.getName();
var.anonymous = v.isAnonymous();
}
var.value = resource;
var.types = ValueTypes.RESOURCE;
if (resource instanceof RdbmsURI) {
var.types = ValueTypes.URI;
}
return var;
}
protected List<QueryBindingSet> populateBindingSet(
List<Statement> document, Var subjVar, List<Map.Entry<Var, Var>> predObjVar) {
// convert document to a multimap
Multimap<URI, Statement> docMap = ArrayListMultimap.create();
for (Statement st : document) {
docMap.put(st.getPredicate(), st);
}
List<QueryBindingSet> results = new ArrayList<QueryBindingSet>();
QueryBindingSet bs0 = new QueryBindingSet(bindings);
// QueryBindingSet result = new QueryBindingSet(bindings);
if (document.size() > 0) {
Statement stmt = document.get(0);
if (subjVar != null && !bs0.hasBinding(subjVar.getName())) {
bs0.addBinding(subjVar.getName(), stmt.getSubject());
}
}
results.add(bs0);
// for (Statement st : document) {
for (Map.Entry<Var, Var> entry : predObjVar) {
Var predVar = entry.getKey();
Var objVar = entry.getValue();
// if (predVar.hasValue() && !st.getPredicate().equals(predVar.getValue()))
// continue;
if (predVar == null || !predVar.hasValue()) continue;
Collection<Statement> predSts = docMap.get((URI) predVar.getValue());
// if (predVar != null && !result.hasBinding(predVar.getName()))
// result.addBinding(predVar.getName(), st.getPredicate());
// if (objVar != null && !result.hasBinding(objVar.getName()))
// result.addBinding(objVar.getName(), st.getObject());
populateBindingSets(results, predVar, objVar, predSts);
}
// }
return results;
}
/**
* Provides a string representation of an SP which contains info about whether each component
* (subj, pred, obj) is constant and its data and data type if it is constant.
*
* @param sp - The statement pattern to convert. (not null)
* @return A String representation of the statement pattern that may be used to do triple
* matching.
*/
public static String toStatementPatternString(final StatementPattern sp) {
checkNotNull(sp);
final Var subjVar = sp.getSubjectVar();
String subj = subjVar.getName();
if (subjVar.isConstant()) {
subj = subj + TYPE_DELIM + URI_TYPE;
}
final Var predVar = sp.getPredicateVar();
String pred = predVar.getName();
if (predVar.isConstant()) {
pred = pred + TYPE_DELIM + URI_TYPE;
}
final Var objVar = sp.getObjectVar();
String obj = objVar.getName();
if (objVar.isConstant()) {
final RyaType rt = RdfToRyaConversions.convertValue(objVar.getValue());
obj = obj + TYPE_DELIM + rt.getDataType().stringValue();
}
return subj + DELIM + pred + DELIM + obj;
}
@Override
protected void meetSP(StatementPattern node) throws Exception {
StatementPattern sp = node.clone();
final Var predVar = sp.getPredicateVar();
URI pred = (URI) predVar.getValue();
String predNamespace = pred.getNamespace();
final Var objVar = sp.getObjectVar();
final Var cntxtVar = sp.getContextVar();
if (objVar != null
&& !RDF.NAMESPACE.equals(predNamespace)
&& !SESAME.NAMESPACE.equals(predNamespace)
&& !RDFS.NAMESPACE.equals(predNamespace)
&& !EXPANDED.equals(cntxtVar)) {
URI transPropUri = (URI) predVar.getValue();
if (inferenceEngine.isTransitiveProperty(transPropUri)) {
node.replaceWith(
new TransitivePropertySP(
sp.getSubjectVar(), sp.getPredicateVar(), sp.getObjectVar(), sp.getContextVar()));
}
}
}
protected BindingSet populateBindingSet(Statement st, List<Map.Entry<Var, Var>> predObjVar) {
QueryBindingSet result = new QueryBindingSet(bindings);
for (Map.Entry<Var, Var> entry : predObjVar) {
Var predVar = entry.getKey();
Var objVar = entry.getValue();
if (predVar != null && !result.hasBinding(predVar.getName()))
result.addBinding(predVar.getName(), st.getPredicate());
if (objVar != null && !result.hasBinding(objVar.getName()))
result.addBinding(objVar.getName(), st.getObject());
}
return result;
}
/**
* Create a QueryBuilder for creating a describe query
*
* @param theVars the variables to be described
* @param theValues the specific bound URI values to be described
* @return a describe query builder
*/
public static QueryBuilder<ParsedGraphQuery> describe(String[] theVars, Resource... theValues) {
QueryBuilder<ParsedGraphQuery> aBuilder =
new AbstractQueryBuilder<ParsedGraphQuery>(new ParsedGraphQuery());
aBuilder.reduced();
aBuilder.addProjectionVar("descr_subj", "descr_pred", "descr_obj");
GroupBuilder<?, ?> aGroup = aBuilder.group();
if (theVars != null) {
for (String aVar : theVars) {
Var aVarObj = new Var(aVar);
aVarObj.setAnonymous(true);
aGroup
.filter()
.or(
new SameTerm(aVarObj, new Var("descr_subj")),
new SameTerm(aVarObj, new Var("descr_obj")));
}
}
if (theValues != null) {
for (Resource aVar : theValues) {
Var aSubjVar = new Var("descr_subj");
aSubjVar.setAnonymous(true);
Var aObjVar = new Var("descr_obj");
aObjVar.setAnonymous(true);
aGroup
.filter()
.or(
new SameTerm(new ValueConstant(aVar), aSubjVar),
new SameTerm(new ValueConstant(aVar), aObjVar));
}
}
aGroup.atom("descr_subj", "descr_pred", "descr_obj");
return aBuilder;
}
@Override
public void meet(Var var) {
if (var.getValue() == null) vars.add(var.getName());
super.meet(var);
}
@Override
public void meet(Var node) throws RuntimeException {
// distinguish between the case where the variable is plain and the variable is bound
SQLVariable sv = parent.getVariables().get(node.getName());
if (sv == null) {
builder.append("NULL");
} else if (sv.getBindings().size() > 0) {
// in case the variable is actually an alias for an expression, we evaluate that expression
// instead, effectively replacing the
// variable occurrence with its value
sv.getBindings().get(0).visit(this);
} else {
String var = sv.getAlias();
if (sv.getProjectionType() != ValueType.NODE && sv.getProjectionType() != ValueType.NONE) {
// in case the variable represents a constructed or bound value instead of a node, we need
// to
// use the SQL expression as value; SQL should take care of proper casting...
// TODO: explicit casting needed?
builder.append(sv.getExpressions().get(0));
} else {
// in case the variable represents an entry from the NODES table (i.e. has been bound to a
// node
// in the database, we take the NODES alias and resolve to the correct column according to
// the
// operator type
switch (optypes.peek()) {
case STRING:
Preconditions.checkState(var != null, "no alias available for variable");
builder.append(var).append(".svalue");
break;
case INT:
Preconditions.checkState(var != null, "no alias available for variable");
builder.append(var).append(".ivalue");
break;
case DECIMAL:
case DOUBLE:
Preconditions.checkState(var != null, "no alias available for variable");
builder.append(var).append(".dvalue");
break;
case BOOL:
Preconditions.checkState(var != null, "no alias available for variable");
builder.append(var).append(".bvalue");
break;
case DATE:
Preconditions.checkState(var != null, "no alias available for variable");
builder.append(var).append(".tvalue");
break;
case TZDATE:
Preconditions.checkState(var != null, "no alias available for variable");
builder.append(parent.getDialect().getDateTimeTZ(var));
break;
case URI:
Preconditions.checkState(var != null, "no alias available for variable");
builder.append(var).append(".svalue");
break;
case TERM:
case NODE:
if (sv.getExpressions().size() > 0) {
// this allows us to avoid joins with the nodes table for simple expressions that only
// need the ID
builder.append(sv.getExpressions().get(0));
} else {
Preconditions.checkState(var != null, "no alias available for variable");
builder.append(var).append(".id");
}
break;
}
}
}
}
private TupleExpr buildConstructor(
TupleExpr bodyExpr,
TupleExpr constructExpr,
boolean explicitConstructor,
boolean distinct,
boolean reduced) {
TupleExpr result = bodyExpr;
// Retrieve all StatementPattern's from the construct expression
List<StatementPattern> statementPatterns = StatementPatternCollector.process(constructExpr);
Set<Var> constructVars = getConstructVars(statementPatterns);
// Note: duplicate elimination is a two-step process. The first step
// removes duplicates from the set of constructor variables. After this
// step, any bnodes that need to be generated are added to each solution
// and these solutions are projected to subject-predicate-object
// bindings.
// Finally, the spo-bindings are again filtered for duplicates.
if (distinct || reduced) {
// Create projection that removes all bindings that are not used in
// the
// constructor
ProjectionElemList projElemList = new ProjectionElemList();
for (Var var : constructVars) {
// Ignore anonymous and constant vars, these will be handled
// after
// the distinct
if (!var.isAnonymous() && !var.hasValue()) {
projElemList.addElement(new ProjectionElem(var.getName()));
}
}
result = new Projection(result, projElemList);
// Filter the duplicates from these projected bindings
if (distinct) {
result = new Distinct(result);
} else {
result = new Reduced(result);
}
}
// Create BNodeGenerator's for all anonymous variables
Map<Var, ExtensionElem> extElemMap = new HashMap<Var, ExtensionElem>();
for (Var var : constructVars) {
if (var.isAnonymous() && !extElemMap.containsKey(var)) {
ValueExpr valueExpr = null;
if (var.hasValue()) {
valueExpr = new ValueConstant(var.getValue());
} else if (explicitConstructor) {
// only generate bnodes in case of an explicit constructor
valueExpr = new BNodeGenerator();
}
if (valueExpr != null) {
extElemMap.put(var, new ExtensionElem(valueExpr, var.getName()));
}
}
}
if (!extElemMap.isEmpty()) {
result = new Extension(result, extElemMap.values());
}
// Create a Projection for each StatementPattern in the constructor
List<ProjectionElemList> projections = new ArrayList<ProjectionElemList>();
for (StatementPattern sp : statementPatterns) {
ProjectionElemList projElemList = new ProjectionElemList();
projElemList.addElement(new ProjectionElem(sp.getSubjectVar().getName(), "subject"));
projElemList.addElement(new ProjectionElem(sp.getPredicateVar().getName(), "predicate"));
projElemList.addElement(new ProjectionElem(sp.getObjectVar().getName(), "object"));
projections.add(projElemList);
}
if (projections.size() == 1) {
result = new Projection(result, projections.get(0));
// Note: no need to apply the second duplicate elimination step if
// there's just one projection
} else if (projections.size() > 1) {
result = new MultiProjection(result, projections);
if (distinct) {
// Add another distinct to filter duplicate statements
result = new Distinct(result);
} else if (reduced) {
result = new Reduced(result);
}
} else {
// Empty constructor
result = new EmptySet();
}
return result;
}
private String getVariableAlias(Var var) {
return parent.getVariables().get(var.getName()).getAlias();
}
private Value getConstantValue(Var var) {
return (var != null) ? var.getValue() : null;
}
private Resource[] getContexts(Var var) {
return (var == null || !var.hasValue())
? new Resource[0]
: new Resource[] {(Resource) var.getValue()};
}
