WHERE content

Accessing the WHERE form of a SPARQL requust can be performed with the ISparqlRequestGroup.getWhereForm() method.

For example:

   SparqlRequest request = new SparqlRequest("sitac");
   request.addSelect("elt");
   WhereForm form = request.getWhereForm();
   form.addType("elt", "Aircraft");
   String query = request.getSPARQL();

Adding expressions in the WHERE form

Adding expressions in the ASK form can be performed directly in the WhereForm, or through the ISparqlRequestGroup.



For example, the following are equivalent:

   SparqlRequest request = new SparqlRequest("sitac");
   request.addSelect("elt");
   WhereForm form = request.getWhereForm();
   form.addType("elt", "Aircraft");
   String query = request.getSPARQL();

or

   SparqlRequest request = new SparqlRequest("sitac");
   request.addSelect("elt");
   request.addType("elt", "Aircraft");
   String query = request.getSPARQL();

Additional variables

• The ISparqlRequestGroup.addAdditionalVariable(String var) method adds an additional variable which will be used in the WHERE part of the request. Return true if the variable could be added (which means it was not already defined in the SELECT part of the request)
• The ISparqlRequestGroup.addAutoVariable() method adds a variable with an unused automatically specified name, to be used in the WHERE part of the request. Return the variable name

Prefixed names

Many of the constructs defined in the SPARQLRequest use PrefixedNames as keys.

Adding a rdf contruct

• The ISparqlRequestGroup.addType(String var, String type) method adds a rdf:type property for a variable in the WHERE part of the request. Return true if the variable has been defined
• The ISparqlRequestGroup.addSubClassOf(String var, String type) method adds a rdf:subClassOf for a variable in the WHERE part of the request. Return true if the variable has been defined
• The ISparqlRequestGroup.addSubClassOfStar(String var, String type) method adds a rdf:subClassOf* for a variable in the WHERE part of the request. Return true if the variable has been defined

Specifying the type of a variable

The ISparqlRequestGroup.addType(String var, String type) method allows to specify a rdf:type for a variable. For example:

   SparqlRequest request = new SparqlRequest("sitac");
   request.addSelect("zone");
   request.addType("zone", "TaskZone");

Will return the following SPARQL content:

   SELECT ?zone
   WHERE {
      ?zone rdf:type sitac:TaskZone .
   }

Specifying the subclass of a variable

The ISparqlRequestGroup.addSubClassOf(String var, String type) method allows to specify a rdf:subClassOf for a variable. For example:

   SparqlRequest request = new SparqlRequest("sitac");
   request.addSelect("zone");
   request.addSubClassOf("zone", "TaskZone");

Will return the following SPARQL content:

   SELECT ?zone
   WHERE {
      ?zone rdf:subClassOf sitac:TaskZone .
   }

The ISparqlRequestGroup.addSubClassOfStar(String var, String type) method allows to specify a rdf:subClassOf* for a variable^[1]

See SPARQL 1.1 Query Language

. For example:

   SparqlRequest request = new SparqlRequest("sitac");
   request.addSelect("zone");
   request.addSubClassOfStar("zone", "TaskZone");

Will return the following SPARQL content:

   SELECT ?zone
   WHERE {
      ?zone rdf:subClassOf* sitac:TaskZone .
   }

Adding a property

• The ISparqlRequestGroup.addPropertyValue(String var, String propertyName, Object propertyValue) method adds a property value specification for a variable property in the WHERE part of the request. Return true if the variable has been defined
• The ISparqlRequestGroup.addPropertyValue(String var, String propertyName, Object propertyValue, boolean optional) method adds a property value specification for a variable property in the WHERE part of the request. Return true if the variable has been defined. The optional parameter allows to define this property value as optional in the request
• The ISparqlRequestGroup.addPropertyValues(String var, List propertyValues) method adds a property value declaration in the WHERE part of the request, for several values
• The ISparqlRequestGroup.addPropertyRef(String var, String propertyName, String varRef) method adds a reference to another variable for a variable property in the WHERE part of the request. Return true if both variables have been defined
• The ISparqlRequestGroup.addPropertyRef(String var, String propertyName, String varRef, boolean optional) method adds a reference to another variable for a variable property in the WHERE part of the request. Return true if both variables have been defined. The optional parameter allows to define this property value as optional in the request
• The ISparqlRequestGroup.addPropertyIndividualRef(String var, String propertyName, String individual) method adds a reference to an individual for a variable property in the WHERE part of the request. Return true if the variable has been defined

Specifying a triple between two variables and a property

The ISparqlRequestGroup.addPropertyRef(String var, String propertyName, String varRef) method allows to specify a triple pattern between two variables and a property. For example:

   SparqlRequest request = new SparqlRequest("sitac");
   request.addSelect("zone");
   request.addAdditionalVariable("index");
   request.addPropertyRef("zone", "hasIndex", "index");  

Will return the following SPARQL content:

   SELECT ?zone
   WHERE {
      ?zone sitac:hasIndex ?index .
   }

Specifying a triple between a variable, a value, and a property

The ISparqlRequestGroup.addPropertyValue(String var, String propertyName, Object propertyValue) method allows to specify a triple pattern between a variable, a value, and a property. For example:

   SparqlRequest request = new SparqlRequest("sitac");
   request.addSelect("zone");
   request.addPropertyValue("zone", "isTasked", true);  

Will return the following SPARQL content:

   SELECT ?zone
   WHERE {
      ?zone sitac:isTasked "true" .
   }

Specifying a triple between a variable, a list of values, and a property

The ISparqlRequestGroup.addPropertyValues(String var, List valuesList) method allows to specify a triple pattern between a variable, a list of values, and a property. For example:

   SparqlRequest request = new SparqlRequest("sitac");
   request.addSelect("zone");
   request.addType("zone", "TaskZone");
   request.addAdditionalVariable("label");
   request.addPropertyRef("zone", "Label", "label");
   request.addPropertyValues("label", SparqlRequest.createValuesList("label1", "label2"));      

Will return the following SPARQL content:

   SELECT ?zone
   WHERE {
      ?zone rdf:type sitac:TaskZone .
      ?zone sitac:Label ?label .
      VALUES ?label {"label1" "label2" }
   }

Adding an individual

The ISparqlRequestGroup.addPropertyIndividualRef(String var, String propertyName, String individual) method allow to set an individual as the target of a property.

For example:

   SparqlPrefixDeclarations decl = new SparqlPrefixDeclarations(false);
   decl.addPrefix("sitac", "http://localhost/SITAC");
   SparqlRequest request = new SparqlRequest("sitac", decl);
   request.addSelect("group0");
   request.addPropertyIndividualRef("group0", "isClassifiedAs", "Own");

Will have the following SPARQL result:

   SELECT ?group0
   WHERE {
      ?group0 sitac:isClassifiedAs ?auto_1 .
      VALUES ?auto_1 { <http://localhost/SITAC#Own> }
   }

Groups

• The SPARQLRequest.addOptionalConstruct() method creates an OPTIONAL construct within the Sparql request. This construct can contain several expressions
• The SPARQLRequest.addUnionConstruct() method creates a list of UNION constructs within the Sparql request. This construct can contain several groups
• The SPARQLRequest.addInnerQuery() method adds an inner query to this query

Optional constructs

The SPARQLRequest.addOptionalConstruct() method allows to create an OPTIONAL construct within the Sparql request. This construct can contain several expressions. The returned construct have the same API as the root request.

For example, for an OPTIONAL construct for only one property:

   SparqlRequest request = new SparqlRequest("sitac");
   request.addSelect("zone");
   request.addType("zone", "TaskZone");
   request.addPropertyValue("zone", "isTasked", true, true);      

Will return the following SPARQL content:

   SELECT ?zone
   WHERE {
      ?zone rdf:type sitac:TaskZone .
      OPTIONAL { ?zone sitac:isTasked "true" }
   }

For an OPTIONAL construct for several properties:

   SparqlRequest request = new SparqlRequest("sitac");
   request.addSelect("zone");
   request.addType("zone", "TaskZone");
   SparqlRequest.Group optional = request.addOptionalConstruct();
   optional.addPropertyValue("zone", "isTasked", true);
   optional.addPropertyValue("zone", "isFriend", true);      

Will return the following SPARQL content:

   SELECT ?zone
   WHERE {
      ?zone rdf:type sitac:TaskZone .
      OPTIONAL {
        ?zone sitac:isFriend "true" .
        ?zone sitac:isTasked "true" .
      }
   }

Unions

The SPARQLRequest.addUnionConstruct() method creates a list of UNION constructs within the Sparql request.

This construct can contain several groups. For example:

   SparqlRequest request = new SparqlRequest("sitac");
   request.addSelect("zone");
   request.addType("zone", "TaskZone");

   Union union = request.addUnionConstruct();
   SparqlRequestGroup group = union.addGroup();
   group.addPropertyValue("zone", "isTasked", true);
   group = union.addGroup();
   group.addPropertyValue("zone", "isFriend", true);      

Will create the following result:

   SELECT ?zone
   WHERE {
      ?zone rdf:type sitac:TaskZone .
   {
      ?zone sitac:isTasked "true" .
   }
   UNION {
      ?zone sitac:isFriend "true" .
   }
   }

Sub-queries

The SPARQLRequest.addInnerQuery() method adds an inner query (sub-query) to a query.

For example:

   SparqlRequest request = new SparqlRequest("map");
   request.addSelect("label");
   request.addSelect("distance");
   request.addSelect("visibility");

   SparqlRequest innerRequest = request.addInnerQuery();
   innerRequest.addSelect("label");
   innerRequest.addSelect("distance");
   innerRequest.addAdditionalVariable("wpt");
   innerRequest.addAdditionalVariable("ac");      
   ...