org.topbraid.spin.model
Class SPINFactory

java.lang.Object
  org.topbraid.spin.model.SPINFactory

public class SPINFactory
extends java.lang.Object

The singleton that is used to convert plain Jena objects into SPIN API resources, and to do corresponding tests.

Author:

Holger Knublauch

Constructor Summary

SPINFactory()

Method Summary

static Command	asCommand(Resource resource) Attempts to cast a given Resource into the most specific subclass of Command, esp Update or Query.
static Element	asElement(Resource resource) Checks whether a given Resource represents a SPARQL element, and returns an instance of a subclass of Element if so.
static RDFNode	asExpression(RDFNode node) Returns the most specific Java instance for a given RDFNode.
static Function	asFunction(Resource resource) Converts a given Resource into a Function instance.
static FunctionCall	asFunctionCall(Resource resource) Checks if a given Resource might represent a Function call, and if yes returns the resource as Function.
static Query	asQuery(Resource resource) Checks if a given Resource is a SPIN query, and returns an instance of a subclass of Query if so.
static Template	asTemplate(Resource resource) Converts a given Resource into a Template instance.
static TemplateCall	asTemplateCall(RDFNode node) Checks whether a given RDFNode can be cast into TemplateCall, and returns it as a TemplateCall instance if so.
static TriplePattern	asTriplePattern(RDFNode node) Checks whether a given RDFNode can be converted into a TriplePattern, and if yes, returns an instance of TriplePattern.
static org.topbraid.spin.model.update.Update	asUpdate(Resource resource) Checks if a given Resource is a subclass of sp:Update and casts it into the most specific Java class possible.
static Variable	asVariable(RDFNode node) Checks whether a given RDFNode can be cast into a Variable and - if yes - converts it into an instance of Variable.
static Argument	createArgument(Model model, Property argProperty, Resource argType, boolean optional) Creates an spl:Argument with a given property and value type.
static Ask	createAsk(Model model, ElementList where) Creates an Ask query for a given WHERE clause.
static Attribute	createAttribute(Model model, Property argProperty, Resource argType, java.lang.Integer minCount, java.lang.Integer maxCount) Creates a new spl:Attribute as a blank node in a given Model.
static ElementList	createElementList(Model model, Element[] elements) Creates a new ElementList in a given Model.
static ElementList	createElementList(Model model, java.util.Iterator<Element> elements) Creates a new ElementList in a given Model.
static Filter	createFilter(Model model, RDFNode expression) Creates a Filter from a given expression.
static FunctionCall	createFunctionCall(Model model, Resource function) Creates a new Function call, which is basically an instance of the function's class.
static Let	createLet(Model model, Variable variable, RDFNode expression) Creates a Let in a given Model as a blank node.
static NamedGraph	createNamedGraph(Model model, Resource graphNameNode, RDFList elements) Creates a new NamedGraph element as a blank node in a given Model.
static NotExists	createNotExists(Model model, ElementList elements) Creates a new NotExists as a blank node in a given Model.
static Optional	createOptional(Model model, ElementList elements) Creates a new Optional as a blank node in a given Model.
static Service	createService(Model model, Resource serviceURI, ElementList elements)
static SubQuery	createSubQuery(Model model, Query subQuery) Creates a new SubQuery as a blank node in a given Model.
static TemplateCall	createTemplateCall(Model model, Resource template) Creates a new TemplateCall as a blank node instance of a given template.
static TriplePath	createTriplePath(Model model, Resource subject, Resource path, RDFNode object) Creates a new TriplePath as a blank node in a given Model.
static TriplePattern	createTriplePattern(Model model, Resource subject, Resource predicate, RDFNode object) Creates a new TriplePattern as a blank node in a given Model.
static Union	createUnion(Model model, ElementList elements) Creates a new UNION element as a blank node in a given Model.
static Variable	createVariable(Model model, java.lang.String varName) Creates a new Variable as a blank node in a given Model.
static Attribute	getAttribute(Resource cls, Property property) Gets an spl:Attribute defined for a given property on a given class.
static Resource	getTemplateMetaClass(Command command) Gets the most appopriate metaclass to wrap a given Command into a Template.
static boolean	isAbstract(Resource module) Checks whether a given module has been declared abstract using spin:abstract
static boolean	isElementList(Resource resource) Checks if a given Resource can be cast into an ElementList.
static boolean	isModuleInstance(Resource resource) Checks if a given Resource is an instance of a class that has type spin:Module (or its subclasses such as spin:Function).
static boolean	isQueryProperty(Property predicate) Checks if a given Property is spin:query or a sub-property of it.
static boolean	isTemplateCall(RDFNode node) Checks whether a given RDFNode is a TemplateCall.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SPINFactory

public SPINFactory()

Method Detail

asCommand

public static Command asCommand(Resource resource)

Attempts to cast a given Resource into the most specific subclass of Command, esp Update or Query.

Parameters:

resource - the Resource to cast

Returns:

resource cast into the best possible type or null

asElement

public static Element asElement(Resource resource)

Checks whether a given Resource represents a SPARQL element, and returns an instance of a subclass of Element if so.

Parameters:

resource - the Resource to check

Returns:

Resource as an Element or null if resource is not an element

asExpression

public static RDFNode asExpression(RDFNode node)

Returns the most specific Java instance for a given RDFNode. If the node is a function call, it will be returned as instance of Function. If it's a Variable, the Variable will be returned. Otherwise the node itself will be returned.

Parameters:

node - the node to cast

Returns:

node or node as a Function or Variable

asFunction

public static Function asFunction(Resource resource)

Converts a given Resource into a Function instance. No other tests are done.

Parameters:

resource - the Resource to convert

Returns:

the Function

asFunctionCall

public static FunctionCall asFunctionCall(Resource resource)

Checks if a given Resource might represent a Function call, and if yes returns the resource as Function. The condition here is fairly general: a function call must be a blank node with an rdf:type triple where the type triple's object is a URI resource. It is generally assumed that this function is called after other options have been exhausted. For example, in order to test whether a resource is a variable or a function call, the variable test must be done first as it is more specific than these test conditions

Parameters:

resource - the Resource to test

Returns:

resource as a Function or null if resource cannot be cast

asQuery

public static Query asQuery(Resource resource)

Checks if a given Resource is a SPIN query, and returns an instance of a subclass of Query if so.

Parameters:

resource - the Resource to test

Returns:

resource as a Query or null

asTemplate

public static Template asTemplate(Resource resource)

Converts a given Resource into a Template instance. No other tests are done.

Parameters:

resource - the Resource to convert

Returns:

the Template

asTemplateCall

public static TemplateCall asTemplateCall(RDFNode node)

Checks whether a given RDFNode can be cast into TemplateCall, and returns it as a TemplateCall instance if so.

Parameters:

node - the node to convert

Returns:

an instance of TemplateCall or null

asTriplePattern

public static TriplePattern asTriplePattern(RDFNode node)

Checks whether a given RDFNode can be converted into a TriplePattern, and if yes, returns an instance of TriplePattern.

Parameters:

node - the node to test

Returns:

node as TriplePattern or null

asUpdate

public static org.topbraid.spin.model.update.Update asUpdate(Resource resource)

Checks if a given Resource is a subclass of sp:Update and casts it into the most specific Java class possible.

Parameters:

resource - the Resource to cast

Returns:

the Update or null if resource cannot be cast

asVariable

public static Variable asVariable(RDFNode node)

Checks whether a given RDFNode can be cast into a Variable and - if yes - converts it into an instance of Variable. The Resource must have a value for spin:varName.

Parameters:

node - the node to check

Returns:

resource as a Variable or null

createArgument

public static Argument createArgument(Model model,
                                      Property argProperty,
                                      Resource argType,
                                      boolean optional)

Creates an spl:Argument with a given property and value type. The new Argument resource will be a blank node in a given Model.

Parameters:

model - the Model

argProperty - the property or null

argType - the value type or null

optional - true if the Argument shall be optional

Returns:

the new Argument

createAttribute

public static Attribute createAttribute(Model model,
                                        Property argProperty,
                                        Resource argType,
                                        java.lang.Integer minCount,
                                        java.lang.Integer maxCount)

Creates a new spl:Attribute as a blank node in a given Model.

Parameters:

model - the Model to create the attribute in

argProperty - the predicate or null

argType - the value type or null

minCount - the minimum cardinality or null

maxCount - the maximum cardinality or null

Returns:

a new Attribute

createAsk

public static Ask createAsk(Model model,
                            ElementList where)

Creates an Ask query for a given WHERE clause.

Parameters:

model - the Model to create the Ask (blank node) in

where - the elements of the WHERE clause

Returns:

the new Ask query

createElementList

public static ElementList createElementList(Model model,
                                            Element[] elements)

Creates a new ElementList in a given Model.

Parameters:

model - the Model to create the ElementList in

elements - the elements (may be empty)

Returns:

a new ElementList (may be rdf:nil)

createElementList

public static ElementList createElementList(Model model,
                                            java.util.Iterator<Element> elements)

Creates a new ElementList in a given Model.

Parameters:

model - the Model to create the ElementList in

elements - the elements (may be empty)

Returns:

a new ElementList (may be rdf:nil)

createFilter

public static Filter createFilter(Model model,
                                  RDFNode expression)

Creates a Filter from a given expression.

Parameters:

model - the Model to create the (blank node) Filter in

expression - the expression node (not null)

Returns:

a new Filter

createFunctionCall

public static FunctionCall createFunctionCall(Model model,
                                              Resource function)

Creates a new Function call, which is basically an instance of the function's class.

Parameters:

model - the Model to create the function call in

function - the function class (must be a URI resource)

Returns:

a new instance of function

createLet

public static Let createLet(Model model,
                            Variable variable,
                            RDFNode expression)

Creates a Let in a given Model as a blank node.

Parameters:

model - the Model to create the Let in

variable - the Variable to assign

expression - the expression on the right hand side

Returns:

a new Let instance

createNamedGraph

public static NamedGraph createNamedGraph(Model model,
                                          Resource graphNameNode,
                                          RDFList elements)

Creates a new NamedGraph element as a blank node in a given Model.

Parameters:

model - the Model to generate the NamedGraph in

graphNameNode - the URI resource of the graph name

elements - the elements in the NamedGraph

Returns:

a new NamedGraph

createNotExists

public static NotExists createNotExists(Model model,
                                        ElementList elements)

Creates a new NotExists as a blank node in a given Model.

Parameters:

model - the Model to create the NOT EXISTS in

elements - the elements of the NOT EXIST

Returns:

a new NotExists

createOptional

public static Optional createOptional(Model model,
                                      ElementList elements)

Creates a new Optional as a blank node in a given Model.

Parameters:

model - the Model to create the OPTIONAL in

elements - the elements of the OPTIONAL

Returns:

a new Optional

createService

public static Service createService(Model model,
                                    Resource serviceURI,
                                    ElementList elements)

createSubQuery

public static SubQuery createSubQuery(Model model,
                                      Query subQuery)

Creates a new SubQuery as a blank node in a given Model.

Parameters:

model - the Model to create the SubQuery in

subQuery - the nested query

Returns:

a new SubQuery

createTemplateCall

public static TemplateCall createTemplateCall(Model model,
                                              Resource template)

Creates a new TemplateCall as a blank node instance of a given template.

Parameters:

model - the Model to create a template call in

template - the template class

Returns:

the new TemplateCall or null

createTriplePath

public static TriplePath createTriplePath(Model model,
                                          Resource subject,
                                          Resource path,
                                          RDFNode object)

Creates a new TriplePath as a blank node in a given Model.

Parameters:

model - the Model to create the path in

subject - the subject (not null)

path - the path (not null)

object - the object (not null)

Returns:

a new TriplePath

createTriplePattern

public static TriplePattern createTriplePattern(Model model,
                                                Resource subject,
                                                Resource predicate,
                                                RDFNode object)

Creates a new TriplePattern as a blank node in a given Model.

Parameters:

model - the Model to create the pattern in

subject - the subject (not null)

predicate - the predicate (not null)

object - the object (not null)

Returns:

a new TriplePattern

createUnion

public static Union createUnion(Model model,
                                ElementList elements)

Creates a new UNION element as a blank node in a given Model.

Parameters:

model - the Model to create the Union in

elements - the elements

Returns:

a new Union

createVariable

public static Variable createVariable(Model model,
                                      java.lang.String varName)

Creates a new Variable as a blank node in a given Model.

Parameters:

model - the Model

varName - the name of the variable

Returns:

the Variable

getAttribute

public static Attribute getAttribute(Resource cls,
                                     Property property)

Gets an spl:Attribute defined for a given property on a given class. The spl:Attribute must be a direct spin:constraint on the class.

Parameters:

cls - the class

property - the property

Returns:

the Attribute or null if none is found

getTemplateMetaClass

public static Resource getTemplateMetaClass(Command command)

Gets the most appopriate metaclass to wrap a given Command into a Template. For example, for an Ask query, this will return spin:AskTemplate.

Parameters:

command - the Command, cast into the best possible subclass

Returns:

the Template metaclass

isAbstract

public static boolean isAbstract(Resource module)

Checks whether a given module has been declared abstract using spin:abstract

Parameters:

module - the module to test

Returns:

true if abstract

isElementList

public static boolean isElementList(Resource resource)

Checks if a given Resource can be cast into an ElementList. It must be either rdf:nil or an rdf:List where the first list item is an element using asElement().

Parameters:

resource - the resource to test

Returns:

true if resource is an element list

isModuleInstance

public static boolean isModuleInstance(Resource resource)

Checks if a given Resource is an instance of a class that has type spin:Module (or its subclasses such as spin:Function).

Parameters:

resource - the Resource to check

Returns:

true if resource is a Module

isQueryProperty

public static boolean isQueryProperty(Property predicate)

Checks if a given Property is spin:query or a sub-property of it.

Parameters:

predicate - the Property to test

Returns:

true if predicate is a query property

isTemplateCall

public static boolean isTemplateCall(RDFNode node)

Checks whether a given RDFNode is a TemplateCall. The condition for this is stricter than for asTemplateCall as the node also must have a valid template assigned to it, i.e. the type of the node must be an instance of spin:Template.

Parameters:

node - the RDFNode to check

Returns:

true if node is a TemplateCall